Acta physiologica Hungarica最新文献

Effect of a new acetylcholine-esterase reactivator, K203 as a new potential antidote in organophosphate intoxications was studied on dopamine (DA), homovanillic acid (HVA), serotonin (5-HT) and 5-hydroxyindolacetic acid (5-HIAA) levels in seven brain regions (cerebellum, spinal cord, hippocampus, hypothalamus, striatum, medulla oblongata and frontal cortex) of rats by an optimized and validated HPLC method. No significant change in brain level of these neurotransmitters was found either 15 or 60 min following treatment. However, when 5-HIAA/5-HT ratios were calculated as measure of turnover, significant decreases were found in the cerebellum, hippocampus, hypothalamus and the frontal cortex 15 min following K203 administration, but after 60 min only in the frontal cortex.

The purpose of the present study was to examine how end tidal CO(2) pressure (PETCO(2)) is controlled in impulse exercise. After pre-exercise at 25 watts for 5 min, impulse exercise for 10 sec with 200 watts followed by post exercise at 25 watts was performed. Ventilation (VE) significantly increased until the end of impulse exercise and significantly re-increased after a sudden decrease. Heart rate (HR) significantly increased until the end of impulse exercise and then decreased to the pre-exercise level. PETCO(2) remained constant during impulse exercise. PETCO(2) significantly increased momentarily after impulse exercise and then significantly decreased to the pre-exercise level. PETCO(2) showed oscillation. The average peak frequency of power spectral density in PETCO(2) appeared at 0.0078 Hz. Cross correlations were obtained after impulse exercise. The peak cross correlations between VE and PETCO(2), HR and PETCO(2), and VE and HR were 0.834 with a time delay of -7 sec, 0.813 with a time delay of 7 sec and 0.701 with a time delay of -15 sec, respectively. We demonstrated that PETCO(2) homeodynamics was interactively maintained by PETCO(2) itself, CO(2) transportation (product of cardiac output and mixed venous CO(2) content) into the lungs by heart pumping and CO(2) elimination by ventilation, and it oscillates as a result of their interactions.

Aluminum (Al) and indium (In) have embryotoxic, neurotoxic and genotoxic effects, oxidative stress being one of the possible mechanisms involved in their cytotoxicity. We have recently demonstrated that indium intraperitoneal (ip) administration induced histological disorganization of testicular tissue. In the present research we aimed at investigating the effect of Al and In ip administration on systemic and testicular oxidative stress status. Studies were performed on Wistar rats ip injected with Al, In or physiological solution for two weeks. Our results showed that In significantly decreased the absolute weight of testicles. Measurements of lactate dehydrogenase (LDH) and paraoxonase (PON) activities showed that In induced a significant augmentation in the first parameter but no changes were observed in the second. Both Al and In caused oxidative stress in testicles by increasing malondialdehyde (MDA) and protein carbonyls (PC) production. Concomitantly, thiol group (-SH) and glutathione (GSH) level were enhanced in the testicles. In the blood, while concentrations of MDA was not changed, those of GSH was significantly decreased in the Al and In groups. Our results indicated that Al and In cause oxidative stress both in blood and testicles but In has cytotoxic effect as well as negative impact on testicle weights. These findings could explain the testicular histological alterations previously described after In ip administration.

Unlabelled: Gastric ulcer is a common gastrointestinal disease. One suggested mechanism is increased oxidative stress. Puplished data showed that dehydroepiandrosterone (DHEA) may limit oxidative stress and lipid peroxidation.

Objective: To investigate the protective effect of DHEA on indomethacin-induced gastric ulcers in rats.

Methods: Forty male rats were randomly divided into four groups: l)

Control group: receive the vehicle, 2) DHEA-treated group, 3) Indomethacin-induced ulcer group and 4) DHEA pretreated (prior to indomethacin) group. At the end of the experiment, rats were killed and the gastric contents were collected to determine the pH and acid concentration. Gastric mucosa was examined macroscopically and then parts of the tissues were collected for histopathological examination. Other parts of the gastric mucosa were homogenized to measure the levels of lipid peroxidation and oxidative stress parameters.

Results: Indomethacin-treated rats showed increased gastric acidity, acid concentration and ulcer index as compared to control rats. This is confirmed by histopathological studies. DHEA pre-treatment proir to indomethacin administration ameliorated all changes seen in the ulcered group.

Conclusion: DHEA has a protective effect against indomethacin-induced gastric ulcers through decreasing acid secretion, prevention of lipid peroxidation and improving endogenous gastric antioxidant system.

Obesity is a pathological condition which increases the risk for cardiovascular disease. The present study was designed to evaluate homocysteine, lipoprotein (a) [Lp(a)], apolipoprotein-B (apo-B), apolipoprotein-A-I (apo-A-I) and lipid indices and their association if any in obese South Indian men. Thirty obese men and thirty age-matched males with normal body weight (controls) were recruited in the study. Plasma homocysteine, Lp(a), lipid profile, apo-A-I and apo-B were estimated in all the subjects. Lipid indices such as lipid pentad index (LPI), lipid tetrad index (LTI), atherogenic index of plasma (AIP), non-high density lipoprotein (non-HDL)/high density lipoprotein (HDL) ratio and apo-B/apo-A-I ratio were calculated in all study subjects. Homocysteine, Lp(a), apo-B, apo-B/apo-A-I ratio and lipid indices were significantly increased in obese men, compared to controls. Both homocysteine and Lp(a) were positively correlated with BMI, waist, hip circumference and apo-B and negatively correlated with apo-A-I. Also we found highly significant positive correlation between homocysteine and Lp(a) levels. The data from the present study concludes that non-conventional risk factors like homocysteine, Lp (a), apo-B/apo-A-I ratio, LTI, LPI, non-HDL/HDL ratio and AIP were significantly elevated in obese Indian men, suggesting they are more prone to develop cardiovascular disease, than the age-matched men with normal body weight.

Unlabelled: Estrogen (E(2)) and progesterone (P) hormones have a pro-inflammatory and an anti-inflammatory role under different conditions. The current study explored this phenomenon in the context of septic inflammation.

Materials and methods: This study involved 48 female albino rats. E(2) (4 mg/100 g body weight (b.w.) and P (5 mg/kg b.w.) were administered to ovariectomized (OVX) rats after systemic inflammation (SI) induced by puncturing the caecum I cm from its end with a single hole by using a 21-gauge needle. Key indices of inflammation and apoptosis were evaluated.

Results: OVX animals subjected to SI showed significantly increased levels of serum tumor necrosis factor-alpha (TNF-u), C reactive protein (CRP) and alanine aminotransferase (ALT). They also showed higher levels of expression of the enzyme inducible nitric oxide synthase (iN OS); 312 ± 43 mg/ml; in the liver, and the activity of both cyclooxygenase 2 (COX-2); 59.4 ± 3.2 U/ml; and caspase 3 enzymes; 6.3 ± 0.54 ng/ml; when compared to non-OVX animals subjected to (SI), (180 ± 3 mg/ml, 16.4 ± 1.69 U/ml, 0.98 ± 0.23 ng/ml respectively). Administration of E(2) resulted in a significant reduction of all serum and liver tissue parameters of inflammation (e.g.decreased iNOS; 193 ± 28 mg/ml and COX-2; 27.6 ± 3.91 U/ml) and decreased apoptosis (Caspase 3; 1.18 ± 0.21 ng/ml). In contrast, OVX animals injected with P before induction of SI showed a significant rise of all measured parameters.

Conclusions: E(2) and Pin physiological levels have contrasting though complementary roles in regulation of the immune system possibly allowing a limited inflammatory response while preventing excessive damage to the tissues.

Previous studies of central diabetes insipidus suggested that thiazides acutely exerted a paradoxical antidiuresis by either indirectly activating volume-homeostatic reflexes to decrease distal fluid-delivery, or directly stimulating distal water-reabsorption. This study investigated whether the direct and indirect actions of bendroflumethiazide (BFTZ) simultaneously cooperated and also whether the renal nerves were involved in inducing long-term antidiuresis in nephrogenic diabetes insipidus (NDI). BFTZ or vehicle was gavaged into bilateral renal denervated and innervated rats with lithium-induced NDI for 10 days, constituting four groups. At one day before (D0) and one, five and ten days after starting administration of BFTZ or vehicle, rats were placed in metabolic cages to collect urine for 6 hours. BFTZ-treatment in both renal innervated and denervated rats caused equivalent reductions in urine-flow, creatinine clearance, lithium clearance and free-water clearance, but rises in urine-osmolality, fractional proximal reabsorption and fractional distal reabsorption at all days compared to D0, as well as to those of their relevant vehicle-received group. Therefore, the chronic antidiuretic response to BFTZ in conscious NDI rats was exerted through a concomitant cooperation of its direct distal effect of stimulating water-reabsorption and its indirect effect of reducing distal fluid-delivery by activating volume-homeostatic mechanisms, which appeared independent of the renal nerves.

Unlabelled: This study is to explore the effect of ALAD polymorphism on hematopoietic, hepatic and renal toxicity from lead in occupational exposure workers.

Methods: We conducted a cross-sectional study on 156 workers with occupational exposure to lead between 2002 and 2007. The results of laboratory examinations were analyzed.

Results: The authors found that workers with the ALAD 1-1 genotype were associated with higher blood lead level than those with the ALADl-2 genotype. Blood and urine lead levels were much higher in storage battery workers than in cable workers. The urine ALA and blood ZPP levels in workers with the ALAD 1-1 genotype were higher than those with the ALADl-2 genotype. The serum Cr level in workers with the ALADl-1 genotype was much higher than those with the ALADl-2 genotype especially in higher lead exposure level.

Conclusions: The ALAD-2 protein might modify the kinetics of lead in blood at a relatively higher blood lead level and protect against hematopoietic, hepatic and renal toxicity from lead. Urine ALA, blood ZPP and serum Cr levels might be considered as effective biological monitoring partners of lead induced hematopoietic and renal toxicology.