Nigerian Journal of Physiological Sciences最新文献

Acute caffeine exposure had been shown to induce hyperglycemia however; the influence of thyroid hormones on the caffeine-induced hyperglycemia is yet to be established. The present study was therefore designed to investigate the effect of caffeine exposure on blood glucose and hepatic glycogen content in thyroidectomized rats. Sixty adult male Wistar rats were randomly divided into 10 groups as I-X (n=6).  Rats in groups I, III, V, VII and IX were given normal saline, caffeine, prazosin + caffeine, propranolol +caffeine, combined prazosin+ propranolol+caffeine injections respectively while rats in groups  II, IV, VI, VIII and X were thyroidectomized  and treated in similar manner as the normal rats respectively. Surgical removal of the thyroid gland was done in the thyroidectomised groups while sham-operation was done in Normal group to serve as control. After healing and following an overnight fast, the rats were anaesthetized and the femoral vein and carotid artery were cannulated for drug administration and blood glucose measurement respectively. After stabilization, following basal measurements, rats from each group were injected normal saline or caffeine (6mg/kg) while another sets were pre-treated prazosin (0.2 mg/kg), propanolol (0.5 mg/kg) or their combination before caffeine administration. Blood glucose was then monitored for 60 minutes post-injection of caffeine at 5 minutes interval. Liver samples were collected at the end of the observation period for glycogen content determination. Caffeine caused significant increased blood glucose levels in both normal and thyroidectomized rats which were up to 210% and 180% respectively at the peak of their responses. Liver glycogen content of the thyroidectomized rats (3.11 ± 0.20 mg/100g tissue weight) was significantly higher than the normal rats (1.91 ± 0.43 mg/100g tissue weight). These glycogen contents were significantly reduced by caffeine in both normal (0.25 ± 0.04 mg/100g tissue weight) and thyroidectomized rats (1.65 ± 0.16 mg/100g tissue weight) when compared with their controls. The caffeine effects on blood glucose and hepatic glycogen content were abolished by pretreatment with propanolol or a combination of prazosin and propanolol in both normal and thyroidectomized rats but pretreatment with prazosin caused only significant reduction in hyperglycemic response to caffeine. The findings of this study suggest that caffeine-induced hyperglycemia in both normal and thyroidectomized rats are mediated through both alpha and beta adrenoceptors.

Cattle egret (Bubulcus ibis) is a cosmopolitan heron species, with least concern conservation status. There are limited literatures on the anatomy of this bird, especially in relation to its sensory organs, hence we here investigated the gross morphological and histomorphometric features of its tongue. The tongues of twelve healthy juvenile cattle egrets were examined in situ for morphological appearance and gross morphometric measurements were determined ex situ. Routine histology was conducted on the tongue tissue with parameters such as epithelial and lamina propia heights, lingual muscle and entoglossal cartilage heights evaluated. Grossly, the tongue was divided into three parts name; apex, body and the root. It was arrow shaped, conforming to the shape of the beak, with a laryngeal mound bounded caudally by the pharyngeal papillae at its root. A massive entoglossal cartilage formed the core of the cranial apex, ventral body portion, and caudal aspect of the root. Histologically, the lingual mucosa possessed keratinized squamous epithelium in all its divisions, with spinous conical papillae being characteristic of the cranial apical mucosa. The body lingual mucosa possessed foliate papillae on the dorsal aspects, while filiform papillae were prominent in the ventral portions. The lingual root uniquely possessed numerous glandular ducts in its lamina propia as well as localized adipocytes. Overall, the regression analysis data showed that the body weight can be conveniently predicted from tongue parameters. This study has thus provided additional knowledge on the anatomy of the birds and the generated data could prove useful in comparative regional anatomy.

Dermatoglyphic traits are genetically determined and remain constant until death. Dermatoglyphics features are arranged from patterns, minutiae and ridgeology. This study utilized patterns and minutiae details of fingerprints as a means of sexual differentiation amongst the University of Ibadan community. Three hundred and eighty-four (192 males and 192 females) participants from the University of Ibadan community were recruited using multistage sampling technique. Fingerprints were obtained using fingerprint scanner Dermalog LF10, Hamburg, Germany. GraphPad Prism 7.0 was used for the test of mean of variables. Ulnar loop, whorl and radial loop patterns were found to be predominantly distributed in both male and female in that order. However, the arch pattern was significantly different between female and male. The male subjects had significantly higher total finger ridge count (TFRC). All the analysed minutiae were significantly different between male and female except bridge. The arch pattern, TFRC and level 2 details (minutiae) of dermatoglyphics could be used as markers for sexual differentiation.

In spite of the increasing use and importance of the African giant rat (Cricetomys gambianus Waterhouse) in research, and other fields, like location of landmines, there is still not enough information on their physiology. In this study, we assessed the electrocardiogram, blood pressure, vital parameters and anaesthetic indices of the African giant rat (Cricetomys gambianus Waterhouse), both genders, using diazepam or ketamine as chemical restraints. A total of 24 adult African Giant Rats (AGR), 12 males and 12 females were used in this experiment. The animals were divided into two groups of twelve animals each (6 males and 6 females). One group was assessed for the effect of diazepam, and the other group ketamine. Diazepam (Roche®, Switzerland) was administered intraperitoneally at a dose rate of 7.5 mg/kg, while ketamine was administered intraperitoneally at a dose rate of 45 mg/kg. Parameters measured were recorded from the time desirable sedation was achieved, and every 15 minutes till the animal was awake. Animals administered diazepam took a longer time to sleep or achieve desirable sedative state, a longer time to respond to stimuli before waking up fully and a longer time to be fully awake, relative to ketamine-induced sedation. Ketamine caused a continuous increase in respiratory rate and blood pressure, while diazepam caused a continuous decrease in the respiratory rate. The electrocardiogram showed tachycardia throughout the experiment with the use of both drugs, although this was more pronounced with the use of diazepam, causing a decrease in QRS interval and a decrease in QT interval. Gender differences were observed in most parameters measured. The results obtained gave baseline values for electrocardiogram and blood pressure readings, while also detailing the changes and gender differences observed with sedation. In addition, results indicated ketamine is best used for short procedures and diazepam at a higher dose used for procedures requiring longer time in the African giant rat.

Long-term antiretroviral drug toxicity may exacerbate the impact of HAART-Cyperus esculentus (C. esculentus) interactions on testicular function in HIV-infected individuals. This study examined the ability of C. esculentus plants to treat testicular dysfunction, which is thought to be a probable side effect of antiretroviral toxicity. Adult Wistar male rats weighing 90-110 g were divided into six groups and administered the prescribed treatments. In addition to testicular histology and stereological parameters, testosterone levels, follicle-stimulating hormone levels, antioxidant markers, malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione levels were also evaluated. The adverse consequences of highly active antiretroviral therapy (HAART) include considerable loss of germ cells, enlargement of the tubular lumen, widening of interstitial gaps, and severe hypocellularity. Compared to the other treatment groups, MDA levels dramatically increased, whereas GSH and antioxidant enzyme (SOD) levels significantly decreased. Testicular architecture was largely conserved after treatment with C. esculentus, with a notable increase in the cellular densities of germinal and interstitial cells and a notable decrease in the tubular lumen. Vacuolation, architectural malformations, and hypoplastic changes were reduced. Significant improvements were also observed in C. esculentus in terms of elevated antioxidant SOD and GSH levels and decreased MDA levels. C. esculentus reduced architectural distortions and testicular dysfunction caused by HAART, and improved testicular morphology. Further exploration of these pathways is required.

Gastric ulcer healing is impaired in both hypothyroid and hyperthyroid conditions.  Thyroid hormones regulate growth, energy metabolism and mitochondrial oxidative metabolism. Xenobiotics have been documented to negatively impact the thyroid gland at high doses but the redox and cellular interactions at low doses during wound healing process remains unclear. Potassium bromate has been documented to be toxic at high doses but there is dearth of information on its activities at a low dose in varied thyroid states which was evaluated in this study. 60 male Wistar rats (g, n=10) were randomised into 2 conditions: Normal, ulcerated untreated, ulcerated treated with 12.5mg/kg p.o KBrO3 and thyroidectomised groups: thyroidectomised ulcerated, thyroidectomised ulcer treated with KBrO3 and thyroidectomised treated with thyroxine (100µg/kg) Total thyroidectomy was used to model hypothyroidism, and ischaemia-reperfusion-induced gastric ulcers were monitored for healing. Daily body weights, Levels of thyroxine, Gastric mucin content, redox and sodium pump activity were examined alongside other markers of hepatic and haematological toxicity by days 3 and 7 post ulceration. Data were analysed using descriptive statistics and ANOVA α 0.05. The bromate-exposed hypothyroid rats showed increased gastric ulcer healing potential with reduced gastric epithelial oedema and inflammation; hepatic steatosis, and periportal inflammation. Haematological variables and markers of hepatic functions were normal. There were reduced levels of gastric and hepatic malondialdehyde levels. Thyroxine and potassium bromate treatment resolved the redox and cellular toxicity possibly via increasing catalase and sulfhydryl levels and increased Na+ K+ pump activity. We conclude that potassium bromate enhanced gastric ulcer healing in hypothyroid state, similar to thyroxine treatment.

The concept of referred pain is an integral part of the anatomy didactic content taught and discussed in all medical school curricula.  However, this discussion has excluded the topic of phantom limb pain, despite the existence of parallels in neurophysiological explanations between these conditions. This brief viewpoint attempts to reason why phantom limb paresthesia or pain should be included in the fold of refereed pain discussions.

This study examines the effect of gestational administration of aqueous leaf extract of Jatropha tanjorensis (JT) on postpartum-like behavioural outcomes to delineate its possibility as a prophylactic, therapeutic agent in the treatment of postpartum symptoms. Inseminated female rats (120-150g) were grouped into two-control and JT group (n=10). Control received 20 ml/kg of distilled water and JT group received 500 mg/kg of JT orally once daily for 21 days in gestation. Non-pregnant rats were excluded from the study. Parameters assessed at postpartum include antidepressant-like (force swim test, FST; tail suspension-test, TST), locomotor (open field test, OFT), anxiolytic-like (elevated plus maze, EPM; light-dark box, LDB), learning and memory (T-maze; novel object recognition task, NORT), social (nest score) and analgesic-like (hot plate test, HPT; tail flick test, TFT) behaviours. JT increased (P<0.05) mobility and latency to immobility durations in FST and TST; open arm entry (P<0.001) and duration (P<0.01) in EPM and light box duration (P<0.05) in LDB; locomotion and exploration, but reduced anxiety-like levels in EPM, LDB and OFT. It increased nest score (P<0.05); mean retraction time (P<0.01) of TFT. JT showed positive score for short and long term memory in NORT and improved percentage alternation in T-maze though not significant compared to control. In conclusion, the aqueous extract has a therapeutic effect that reduces postpartum-like depression and anxiety, and improves locomotor activity. JT can be a preventive and adjuvant therapeutic option for pregnant women.

Anaemia is a widespread health issue affecting young children and pregnant women, characterized by reduced red blood cells or haemoglobin levels. Coconut water, rich in nutrients such as L-arginine, iron, vitamin C, vitamin B6, folic acid and fatty acids, is believed to aid in blood formation (hematopoesis). The study aimed to examine the impact of coconut water on hematological indices and lipid profiles in rats with phenylhydrazine-induced anemia. 30 rats were divided into 5 groups: a normal control, phenylhydrazine untreated, coconut water (0.5ml/kg), iron, and ferrous treated groups. Hemoglobin, hematocrit, and erythrocyte levels were measured using a Hematology Analyzer. Results showed a significant decrease in LDL and TG levels, and an increase in HDL levels in phenylhydrazine induced anemia compared to the control group. Coconut water administration at 0.5ml/kg reduced LDL, VLDL and TG levels, and increased HDL levels in rats with induced anemia. The study found that coconut water had a positive effect on hematological indices, as it increased hemoglobin and erythrocyte levels in rats with induced anemia. These findings suggest that coconut water may have potential therapeutic benefits for individuals with anemia, particularly in lowering lipid levels and improving blood formation. However, further research is needed to fully understand the mechanisms underlying these effects and to determine the most effective dosage and duration of treatment. Overall, the study highlights the importance of coconut water as a potentially beneficial alternative treatment for anemia.