Journal of pharmacological and toxicological methods最新文献

{"title":"Enhancing cardiac safety evaluation: Assessing drug interactions with the late Nav1.5 current","authors":"Eva Vermersch ,&nbsp;Véronique Ballet ,&nbsp;Agnès Jacquet ,&nbsp;Irène Mahfouz ,&nbsp;Jean-Marie Chambard ,&nbsp;Françoise Chesney ,&nbsp;Desirae Martin ,&nbsp;Janette Rodriguez ,&nbsp;Ky Truong ,&nbsp;Najah Abi-Gerges ,&nbsp;Ambroise Garry","doi":"10.1016/j.vascn.2025.107806","DOIUrl":"10.1016/j.vascn.2025.107806","url":null,"abstract":"<div><div>Late Na + current (INa,L) contributes to cardiac action potential (AP) and helps maintain Na + homeostasis. Contrary to the effect on Nav1.5, hERG and Cav1.2 channels, the effect of novel drugs on INa,L is not routinely studied in safety studies. Yet, INa,L inhibitors can counterbalance hERG blockade and be associated with anti-arrhythmic potential. Hence, evaluating the effects of drugs against Nav1.5, hERG and Cav1.2 channels provides valuable cardiotoxic insights, but does not fully predict changes in the electrophysiological and contractile properties of cardiomyocytes. To address this deficiency, we evaluated the effects of selective and non-selective INa,L inhibitors on cardiomyocyte function. Compounds known to inhibit INa,L (GS-967 specific for INa,L; ranolazine specific for both hERG and INa,L; loperamide which is a hERG, Nav1.5 and Cav1.2 inhibitor) and four preclinical compounds were tested for their effects on cardiac ion channels (peak Nav1.5, hERG, Cav1.2 and INa,L) with automated patch-clamp and multi-electrode array (MEA) in hiPSC-derived cardiomyocytes for electrophysiological properties, and contractility in human primary cardiomyocytes from consented donor hearts with MyoBLAZER™. Each compound was tested separately at multiple concentrations in the presence of ATX-II, a selective enhancer of INa,L. GS-967 and ranolazine reversed ATX-II-induced increases in contractility and field potential duration (FPD) in a concentration-dependent manner providing evidence of a functional INa,L in both hiPSC-derived cardiomyocytes and adult cardiomyocytes. Next, we evaluated the effects of four preclinical compounds. Two out of the four compounds showed similar behavior to GS-967 and ranolazine. For example, compound A inhibited ion channels (hERG, Nav1.5, Cav1.2 and INa,L with IC50 values of 7.9 mM, 12.4 mM, 0.8 mM, respectively) and reversed ATX-II changes on contractility and FPD with IC50 values of 0.99 mM and 2.3 mM, respectively. Here, we developed a protocol for assessing drug interactions with INaL on cardiomyocytes. This assay enhances our ability to predict cardiotoxicity potential and its incorporation into the traditional compound derisking strategy strengthens confidence in advancing molecules into clinical development.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107806"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the sensitivity/specificity of statistical analysis strategies for detecting moxifloxacin-induced QTc prolongation","authors":"Lawrence M. Carey,&nbsp;David Holdsworth,&nbsp;Jared Slain,&nbsp;Jill Dalton","doi":"10.1016/j.vascn.2025.107782","DOIUrl":"10.1016/j.vascn.2025.107782","url":null,"abstract":"<div><div>In light of the implementation of the best practice guidelines as outlined in the ICH E14/S7B Q&amp;A's, several strategies for enhancing the sensitivity of statistical analyses to detect drug-induced QT/QTc prolongation have been proposed. This study aimed to assess the sensitivity and selectivity of 3 standard statistical approaches. Moxifloxacin was administered orally at doses of 30, 80 and 175 mg/kg to male cynomolgus monkeys (<em>n</em> = 4) according to a Latin square design. Telemetry endpoints were monitored from 2 h prior to dosing to 24 h postdose. Three analysis strategies were employed to aid in the detection of QTc prolongation. Data were grouped into 3 analysis segments (0–6, 6–18, 18–24 h postdose). Approaches 1 and 2 utilized pairwise comparisons at each hourly interval within these segments or the entire segment based on the significance of the interaction effect, while approach 3 analyzed data pooled within each super-interval. Approach 1 employed a repeated measures analysis of variance (RMANOVA) strategy. Statistical significance was considered to have been attained when the <em>p</em>-value of each comparison was &lt;0.05. Approach 2 utilized an RMANOVA analysis strategy examining the least squares mean differences between each treatment and control. Statistical significance was considered to have been obtained when these differences were greater than or equal to the least significant difference (LSD) for the study and the 95 % confidence intervals (CI) did not cross zero. Approach 3 utilized an analysis of variance approach with statistical significance considered attained when the mean difference between each treatment and control was greater than or equal to the LSD and the 95 % CI did not cross zero. In general, the 3 approaches performed similarly. Approach 3 demonstrated the highest sensitivity (most statistically significant differences identified) while approach 2 displayed the highest selectivity (fewest type I statistical errors). Approach 3 performed better than Approaches 1 and 2 in detecting QTc prolongation. Of note, only approach 3 identified every QTc change greater than 10 msec as significant. All 3 methods of analysis were adequate to detect moderate changes in QT/QTc, though differences in the sensitivity and selectivity were observed between analysis strategies.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107782"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study to compare effects of a positive inotrope administered concurrently with a beta-blocker in ventricular Tachy-Paced dogs in mild heart failure","authors":"Sydney St Clair","doi":"10.1016/j.vascn.2025.107836","DOIUrl":"10.1016/j.vascn.2025.107836","url":null,"abstract":"<div><div>Dilated cardiomyopathy(DCM) is common in dogs and is characterized by dilation and impaired systolic function of the ventricles. Pimobendan, a positive inotrope, has been suggested to benefit DCM by reducing preload and afterload, providing positive inotropic support, reducing cardiac size and filling pressures. Beta-blockers are used to treat ventricular arrhythmias associated with DCM, although there is concern that decreased inotropy could be detrimental to ejection fraction (EF). Given need for multimodal treatments, combined use of pimobendan and beta-blockers could help to mediate the negative inotropy of beta-blockers. This pilot study aims to compare the echocardiographic EF of simultaneous administration of pimobendan and sotalol (beta-blocker) at veterinary dosages in a HF dog model. Seven beagle-dogs were induced into mild HF using a ventricular-tachy-pacing(VTP) model. Dogs received four different treatment regimens: control, pimobendan (0.2–0.3 mg/kg PO BID), sotalol (1-3 mg/kg PO BID), and a combination of pimobendan and sotalol for two-weeks each. Multiple methods of calculating EF via echocardiography were evaluated, including ejection fraction (Eft) and fractional shortening (FS) from M-mode and Simpson's method-of-discs (SimpsonsEF) measured from right parasternal long-axis view, and were recorded at baseline, day 3, 7, and 14. By day 14, echocardiographic data indicated administration of pimobendan resulted in a significant increase in EF compared to baseline (↑ Eft 19.3 ± 3 % ΔBL; ↑ FS 24.1 ± 3.9 %ΔBL; ↑ SimpsonsEF 28.9 %ΔBL). In contrast, sotalol showed a significant decrease in EF compared to baseline (↓ Eft 9.5 ± 6.8; ↓ FS 9.9 ± 8.2; ↓ Simpson's EF 19.1 ± 9.5). The combination therapy of pimobendan and sotalol showed a non-significant increase in EF from baseline (↑ Eft 5.1 ± 5.5; ↑ FS 6.5 ± 6.7; ↑ SimpsonsEF 1.53 ± 9.5), but the change was similar to that of the control group (↑ Eft 3.1 ± 4.4; ↑ FS 4.2 ± 5.3; ↑ SimpsonsEF 3.0 ± 7.2), indicating that the change could be due to day-to-day variation. The study demonstrates that concurrent administration of a positive inotrope with a beta-blocker does not decrease cardiac function, as evidenced by no significant decrease in EF. In dogs with DCM that may benefit from beta-blocker therapy, pimobendan may be added to mitigate negative inotropic effects. This combination of therapies may allow clinicians to optimize treatment in complicated cases, warranting further investigation.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107836"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of multiple concentration-QTc modeling approaches","authors":"Jill Dalton ,&nbsp;Steve Denham ,&nbsp;Matthew St Peter ,&nbsp;Kevin Norton","doi":"10.1016/j.vascn.2025.107775","DOIUrl":"10.1016/j.vascn.2025.107775","url":null,"abstract":"<div><div>The ICH E14/S7B Q&amp;A guidance for <em>in vivo</em> preclinical studies recommends exposure-response modeling to support the assertion that there were no changes in QTc, to better characterize observed QTc prolongation, and/or when QTc changes are anticipated based on hERG assay results. While the guidance indicates that there are multiple acceptable approaches for concentration-QTc modeling, associated training documents and general industry views indicate that assessments should ideally occur in a separate phase of the study utilizing the same animals as those used for telemetry monitoring to generate a complete exposure profile. However, this “gold standard” approach is not necessarily ideal as it requires additional cost, time, and test material. Alternative options have been proposed including partial toxicokinetic profiles utilizing the same animals as those used for telemetry monitoring or by generating full profiles using data collected from a separate cohort of animals. However, it is unclear as to how concentration-QTc data estimates might differ with alternate approaches. The current study utilized moxifloxacin at 10, 30 and 90 mg/kg, PO in beagle dogs using a 4 × 4 cross-over design monitoring QTc via telemetry over 24 h. Plasma concentrations were determined at 0, 2, 4, 6, 8, 12, and 24 h postdose by using the same animals in a separate phase of the telemetry study or by using a separate cohort of animals. The 10 msec prolongation prediction values were estimated for the partial toxicokinetic profiles using data pairs to estimate plasma levels at each time point using the plasma samples collected during the telemetry phase. The actual exposure values were used for the independent groups. Additionally, simulations of possible toxicokinetic curves for the separate groups were used to estimate representative population values. The 10 msec prolongation prediction values varied minimally, with &lt;300 ng/ml difference among the various estimation methods. Therefore, comparison of these exposure-response modeling methods illustrates the relatively small degree of impact that the different approaches have on QTc prediction values as compared to the gold standard methodology, thus providing multiple viable study design options for researchers to consider in their preclinical testing strategies.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107775"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A strategy to predict psychotic risks of drug candidates using auditory steady-state response","authors":"Daigo Homma,&nbsp;Yoshiaki Furuya,&nbsp;Takashi Yoshinaga","doi":"10.1016/j.vascn.2025.107839","DOIUrl":"10.1016/j.vascn.2025.107839","url":null,"abstract":"<div><div>It is difficult to predict the psychiatric adverse effects of drug candidates from preclinical observations especially when the mechanism of actions is novel. Recently, auditory steady-state response (ASSR) in gamma band frequency has been reported as a translational biomarker for psychotic disorders and is thought to reflect the cortical functionality for neuronal oscillations. To investigate its potential for preclinical risk assessment, we evaluated the effects of the psychotogenic drugs, a non-competitive NMDA antagonist MK-801, a dopamine transporter inhibitor methylphenidate and a 5HT2 agonist DOI, on high gamma ASSR from rat auditory cortex using a chirp-modulated tone whose modulation frequency change from 1 to 120 Hz or from 120 to 1 Hz. The effect of MK-801 was very robust that it attenuated the ASSR (83 % reduction in power (<em>p</em> &lt; 0.0001) and 47 % reduction in phase-locking factor (PLF. <em>p</em> &lt; 0.001)) at 1 mg/kg dose. The effect of methylphenidate on ASSR in power was relatively mild while it significantly attenuated PLF by 36 % at 50 mg/kg. The effect of DOI was somewhat different: The administration of 3 mg/kg did not attenuate the ASSR amplitude, but instead increased the chirp-frequency independent high gamma band (power 322 % of control, <em>p</em> &lt; 0.05). These observations resemble the attenuation of phase-locked response and augmentation of non-phase-locked response in schizophrenia patients. In baseline period, the administration of 1 mg/kg of MK-801 or 50 mg/kg of methylphenidate enhanced spontaneous high gamma power (181 % of control for MK-801, p &lt; 0.001, 183 % of control for methylphenidate, p &lt; 0.05), which is also observed in human psychosis. Together with the clinical reports examining the drug effects on ASSR and with pharmacokinetic models from the literatures, our results suggest that ASSR and the related EEG response in high gamma band is a promising translational biomarker for the drug-induced psychosis, and that the use of chirp tone enables the clear discrimination of modulation frequency-dependent and -independent effects.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107839"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating a non-invasive telemetry jacket as an alternative to the reference methods for cardio-respiratory safety pharmacological testing in rats","authors":"Fatima-Zahra Khamlichi,&nbsp;Heike Schauerte,&nbsp;Werner Mayer,&nbsp;Leonie-Theresa Hezler,&nbsp;Eric Martel,&nbsp;George Rast,&nbsp;Nicolas Pairet","doi":"10.1016/j.vascn.2025.107767","DOIUrl":"10.1016/j.vascn.2025.107767","url":null,"abstract":"<div><div>The gold standard methods used to assess cardiorespiratory system in rats, whether telemetry implants or whole-body plethysmography (WBP), have their shortcomings. One method requires surgery, while the other involves the isolation of rats. In a 3Rs approach, alternatives such as the use of non-invasive telemetry jackets, allowing simultaneous cardiorespiratory assessment, without hemodynamic parameters evaluation have been considered. No peer-reviewed publication to date has investigated the concordance between cardiorespiratory parameters recorded simultaneously via the jackets and the reference methods, following the administration of a pharmacological compound. Goal: to test and potentially validate the telemetry jackets by comparing data generated using this device with those obtained using gold standard methods at the same time, in the same animal, in an integrative interpretation approach. We compared cardiac (heart rate (HR)) and respiratory (respiratory rate (RR), minute ventilation (MV), tidal volume (TV)) parameters recorded via the invasive (DSI implant), non-invasive (Jacket DECRO) telemetry systems, and via the WBP (Buxco + Notocord HEM), simultaneously in the same male rats (<em>n</em> = 8rats/ pharmacological compound in a cross-over design). The recording lasted 7 h after the per-os administration of vehicle or pharmacological reference compounds tested (Ivabradine or Theophylline) at 3 doses. A generalized linear model was used to assess the effects of the pharmacological compounds. The Bland-Altman method was used to study the agreement between the jackets and the two reference methods. The jackets and reference methods both captured the expected pharmacological effects. For Ivabradine, a significant dose-dependent decrease in HR was observed, while no changes were noted in respiratory variables. Theophylline induced a dose-dependent increase in heart rate and RR. No significant change on TV and MV was noticed with the WBP, whereas a significant increase was shown with the jackets. Bland-Altman analysis revealed an increasing discrepancy in high TV, RR and MV values between the two devices under the experimental conditions of the studies. Jackets can be used as an alternative to implanted telemetry for recording HR without hemodynamic parameters. Although the two respiratory methods detect pharmacological effects, further investigation is needed to determine what is the current state of the respiratory parameters.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107767"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variability of manual patch clamp data on CaV1.2 and NaV1.5 channels generated using standardized protocols and following ICH S7B Q&A 2.1 best practices – Progress update of a HESI-coordinated multi-laboratory study","authors":"Huimei Yu ,&nbsp;Claudia Alvarez Baron ,&nbsp;Jun Zhao ,&nbsp;Ming Ren ,&nbsp;Shovan Naskar ,&nbsp;Donglin Guo ,&nbsp;Manni Mashaee ,&nbsp;Jose Vicente ,&nbsp;Lars Johannesen ,&nbsp;Jiansong Sheng ,&nbsp;Simon Hebeisen ,&nbsp;James Kramer ,&nbsp;Andrew Bruening-Wright ,&nbsp;Koji Nakano ,&nbsp;Jennifer Pierson ,&nbsp;David Strauss ,&nbsp;Wendy W. Wu","doi":"10.1016/j.vascn.2025.107808","DOIUrl":"10.1016/j.vascn.2025.107808","url":null,"abstract":"<div><div>Concomitant block of Ca_V1.2 and/or Na_V1.5 channels may mitigate Torsade de Pointes risk associated with hERG block. However, Ca_V1.2 channel block may cause bradycardia/hypotension; Na_V1.5 channel block may induce conduction slowing and sudden cardiac death in patients with structural heart diseases. Understanding drug effects on multiple cardiac ion channels can be of value for proarrhythmia risk assessment. Literature shows large degrees of lab-to-lab variability for drug potencies on cardiac ion channels. Ion channel data alignment with drug-induced ECG changes can thus be dataset-dependent. Lab-to-lab differences can arise from different experimental protocols and/or data quality. Thus, ICH S7B Q&amp;A 2.1 was released to provide best practice recommendations for conducting cardiac ion channels assays to support proarrhythmia risk assessment. The goal of this HESI-coordinated, multi-laboratory research effort is to generate block potencies for 28 drugs in low, intermediate, and high proarrhythmia risk categories for hERG, Ca_V1.2, and peak and late Na_V1.5 currents with standardized protocols and best practices. This abstract focuses on the Ca_V1.2 and peak and late Na_V1.5 currents; hERG data are presented in a companion abstract (Alvarez-Baron et al.). Five laboratories conducted manual patch clamp experiments at near physiological temperatures on cell lines over-expressing Ca_V1.2 or Na_V1.5 channels. The research is ongoing, hence drug potencies are not presented. Instead, this abstract presents findings on data variability for each current, estimated using meta-analysis to account for drug-specific (i.e., potencies) and laboratory-specific effects. Systematic data variability was not observed from any laboratory for any current. After removing drug- and laboratory-specific effects, residual data variability was pooled across all drugs/laboratories to estimate overall assay variability. Variability measures for Ca_V1.2 and peak and late Na_V1.5 currents will be shared on the poster. This dataset can be compared with existing clinical data to understand nonclinical-clinical translation. Experiments on these three currents are ~75 % complete. Once complete, outcomes of this study will: 1) inform assay variability and support identification of safety margins for Ca_V1.2 and Na_V1.5 channels; and 2) produce a dataset to develop an in-silico myocyte model that can integrate multi-cardiac ion channel data for proarrhythmia risk prediction.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107808"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced cardiotoxicity assessment through propagation pattern analysis using HD-CMOS-MEA in hiPSC-derived cardiomyocytes","authors":"Nami Nagafuku,&nbsp;Naoki Matsuda,&nbsp;Ikuro Suzuki","doi":"10.1016/j.vascn.2025.107810","DOIUrl":"10.1016/j.vascn.2025.107810","url":null,"abstract":"<div><div>Cardiotoxicity is a common reason for drug discontinuation in new drug development. The in vitro microelectrode array (MEA) method using human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) is expected to be an alternative to animal experiments, but hiPSC-CMs cannot mature sufficiently in two-dimensional culture. In addition, the evaluation method of MEA is mainly based on the field potential duration (FPD) as an index, and the mechanism of action based on conduction velocity and propagation pattern has not been predicted. This research aims to construct an evaluation method focusing on conduction velocity and propagation pattern as indices for MEA. To enable detailed analysis, hiPSC-CMs were measured using a high-density (HD)-CMOS-MEA with 236,880-microelectrodes instead of conventional MEA. Pharmacological tests used compounds and concentrations undetectable by conventional MEA, measuring extracellular potentials for 14 compounds, including negative controls. The HD-CMOS-MEA can record a single cell with dozens of electrodes. Seventeen parameters were established for the propagation pattern, including the number of origins, origin position fluctuation, propagation velocity, and propagation area. A specific increase in origins was detected with isoproterenol, an adrenergic β1 receptor agonist. A decrease in propagation velocity was observed with mexiletine, a Na channel inhibitor. A decrease in propagation area was detected with E4031, a hERG potassium channel inhibitor. Furthermore, differences in conduction velocity and propagation pattern based on the mechanism of action of each compound were revealed, suggesting that cardiotoxicity evaluation using CMOS-MEA may capture differences in channel activity for each concentration of compounds with multiple actions with high sensitivity. Additionally, a decrease in propagation area and propagation velocity was detected 24 h after exposure to 0.1 μM doxorubicin, which exhibits cardiotoxicity when administered chronically. Cardiotoxicity evaluation using CMOS-MEA demonstrated that cardiotoxicity could be detected at lower concentrations and shorter durations of chronic administration compared to conventional cardiotoxicity evaluations. This indicates that cardiotoxicity evaluation using HD-CMOS-MEA may detect cardiotoxicity risks that could not be identified by conventional MEA analysis, based on new parameters. This underscores the potential use of imaging technology in drug discovery and compound toxicity evaluation.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107810"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative comparison of ECG limb lead configurations: Evaluating synonymity of interval measurements using alternative leads under appropriately controlled study conditions","authors":"Courtney Jenkins ,&nbsp;Steve Tichenor","doi":"10.1016/j.vascn.2025.107829","DOIUrl":"10.1016/j.vascn.2025.107829","url":null,"abstract":"<div><div>In Safety Pharmacology studies, electrocardiogram (ECG) waveform recording in a lead II configuration is the established gold standard for ECG lead placement. This approach, with proper surgical techniques, yields high fidelity data suitable for quantitative and qualitative assessment. External lead configurations, using either external telemetry (ET) or manual restraint methods, are widely accepted practices to integrate CV assessments on to general toxicology studies. While both methods can provide reliable data, improper lead placement or unexpected displacement of electrodes can compromise data quality, hindering accurate assessment of waveform morphology and interval measurements. The aim of this project was to investigate advantages of a multi‑lead ECG design, focusing on the feasibility of interchanging external lead configurations to provide concurrent comparison within a single study. This approach allowed for direct comparison of measurements obtained from different external lead configurations. Six non-human primates were equipped with Jacketed ET (JET-3ETA, manufactured by Data Sciences International). Following proper animal acclimation, a 24-h ECG recording period was conducted with ECG leads positioned in standard lead I (lateral vector, coronal plane), II (inferior vector, sagittal plane), and III (inferior vector, frontal plane) orientations. Comparison of lead II to lead III demonstrated minimal differences in ECG interval measurements for HR (0.1 %), PR (0.4 %) QRS (0.6 %), RR (0.1 %), QT (1.7 %) and rate corrected QTc (1.9 %), while differences in lead II to lead I orientations were slightly greater: HR (1.0 %), PR (3.3 %) QRS (0.3 %), RR (0.3 %), QT (3.6 %) and rate corrected QTc (3.0 %). The results demonstrated minimal difference among the different limb leads that were within a range of variation that was biologically inconsequential. This suggests that utilization of an external multi‑lead ECG design on a large animal study can improve data yield or quality by incorporating analysis from other leads if the primary lead (lead II) has waveforms that are of unsuitable quality. The synonymous correlation in measurements from lead II to lead III was expected given their similar orientation within the same electrical plane. This supports the feasibility of interchanging data among these external lead configurations without compromise to data interpretation.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107829"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Challenges in adapting a conscious dog haemodynamic systems model to an anaesthetised dog protocol","authors":"Joanne Mahmud ,&nbsp;Chris E. Pollard ,&nbsp;Tariq Abdulla ,&nbsp;Barira Islam ,&nbsp;Yevgeniya E. Koshman ,&nbsp;Michael K. Pugsley ,&nbsp;Will S. Redfern","doi":"10.1016/j.vascn.2025.107831","DOIUrl":"10.1016/j.vascn.2025.107831","url":null,"abstract":"<div><div>Previously¹, the cardiovascular-contractility systems model described by Fu et al.² was evaluated and extended using Simcyp™ Designer, a graphical interface platform and physiologically-based pharmacokinetic tool. Model outputs replicated published dog telemetry data¹. In the present study, the model was adapted for use in pentobarbital-anaesthetised beagle dogs, utilizing cardiovascular (CV) and exposure data for atenolol and atropine³. Model adaptations included removal of circadian rhythm, attenuation of baroreflex negative feedback, and development of a pharmacokinetic model in Simcyp™ Designer to accommodate intravenous dose escalation and hysteresis. Model simulations and experimental data for atenolol (0.3, 1, and 3 mg/kg/30 min) showed a decrease in dP/dt_max from 2300 to 1800 mmHg/s and mean arterial pressure (MAP) from 120 to 110 mmHg. The model predicts a decrease in heart rate (HR) from 110 to 85 bpm; however, bradycardia was not observed experimentally. For atropine (0.01, 0.03, 0.1 mg/kg/30 min), model outputs and experimental data displayed an increase in HR (124 to 164 bpm) and dP/dt_max (2650 to 3000 mmHg/s). While experimental MAP data decreased from 130 to 120 mmHg, model outputs predicted an increase from 105 to 130 mmHg. Several challenges were encountered during the development of the anaesthetised systems model. Firstly, the study design for the anaesthetised dog differs markedly from that of conscious dog telemetry. Secondly, the extent to which the baroreceptor reflex is attenuated by the anesthesia is unknown. Furthermore, the Fu et al. model² employs antagonist K_d values to predict haemodynamic effects, rather than <em>in vivo</em> EC₅₀ values. Finally, the decrease in HR predicted by the model following atenolol administration was not observed in anaesthetised dogs, possibly due to low resting cardiac sympathetic tone under the anesthesia. Despite these limitations, the adapted Fu et al.² model has the potential to maximise the use of anaesthetised CV dog data. Specifically: to interpolate CV effects at intermediate dose levels, derive threshold plasma concentrations for detectable CV effects, and predict the CV effects at doses which cannot be tolerated.</div><div>1. Mahmud et al. (2023) SPS Meeting, Brussels, Belgium</div><div>2. Fu et al. (2022) <span><span>https://doi.org/10.1002/psp4.12774</span><svg><path></path></svg></span></div><div>3. Antic et al. (2024) <span><span>https://doi.org/10.1016/j.vascn.2024.107497</span><svg><path></path></svg></span></div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"135 ","pages":"Article 107831"},"PeriodicalIF":1.8,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145095004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}