Rauvolfia vomitoria Afzel. disrupts dentate gyrus cells

88-94Herbal remedy for neurological problems may have adverse effects, and could prove detrimental if not regulated properly. Rauvolfia vomitoria (RV) is a herb commonly associated with psychiatry management because of its antipsychotic and sedative properties. Here, we studied the effects of the root bark extract of R. vomitoria on the dentate gyrus of adult Wistar rats. Twenty four adult Wistar rats (220 g average) were divided into four groups (n=6); control (placebo), 200, 300 and 400 mg/kg RV root bark extract, respectively for 7 days. The animals were sacrificed 24 h after last administration, and the brains were processed for histology and immunoreactivity. Results showed hypertrophy and atrophy of granule cells in all 200, 300 and 400 mg/kg RV groups, respectively. There was increased neuron specific enolase and glial fibrillary acidic protein expressions in the 200 and 300 mg/kg RV groups, while these proteins expression were decreased in the 400 mg/kg RV group. These results suggest that RV cause dentate gyrus cell injury in a dose-dependent pattern, and may lead to degeneration and disruption of functions

Evaluation of prenatal calabash chalk geophagy on the developing brain of Wistar rats

Calabash chalk (CaC) is an aluminium silicate hydroxide compound with heavy metal constituents, making it a potential neurotoxicant. Pregnant women often consume CaC as an antiemetic, which may interfere with the normal development of the foetal brain. Here, we evaluated the effects of CaC administration in pregnant rats on the brain of the offspring. Wistar rat dams were assigned to one of three groups: control, 200 mg/kg and 800 mg/kg of a CaC suspension. Administrations lasted 14 days (gestation days 7-20). On day 14, 5-bromo-2'-deoxyuridine (BrdU) was administered and dams were allowed to term. Behavioural tests were performed on different days as the pups matured, and they were sacrificed on post-natal days 30 and 60. Brains were processed for histology and Western blotting. Results showed no significant differences in surface righting reflex, cliff avoidance, negative geotaxis and open-field activity. No hippocampal and somatosensory cortical cytoarchitectonic alterations and no significant signs of glial fibrillary acidic protein (GFAP) activation were observed. Neuronal nuclei counts showed variability in the somatosensory cortex and hippocampus of the CaC group. BrdU-positive cells were significantly lower in the 200 mg/kg group and higher in the 800 mg/kg group. Doublecortin-X-positive cells were not different in all the CaC groups. Astrocytes and microglia Western blotting quantification confirmed no significant increase in pup glial cells in adulthood. Prenatal consumption of CaC at indicated dosages may not be deleterious to the developing brain, especially after cessation of exposure and during maturation of the animal. However, the differences in neuronal and glial populations may be due to their ability to cope with CaC

Effect of Calabash Chalk on the Histomorphology of the Gastro-Oesophageal Tract of Growing Wistar Rats

Background: Calabash chalk is a naturally occurring mineral consumed by members of some Nigerian communities for pleasure and by pregnant women as a remedy for morning sickness. The consumption of this geophagic material motivated our interest on the effect of the chalk on the histomorphology of the gastro-oesophageal tract. Methods: Twenty-eight young Wistar rats, 4 weeks old, were divided into 4 groups of equal size. Group 1 animals served as controls and received 1 mL of distilled water. Groups 2, 3, and 4 received orally 1 mL of a Calabash chalk suspension containing 40 mg/mL for 14, 21, and 28 days, respectively. Upon completion of the treatments, the animals in groups 2, 3, and 4 were sacrificed on days 15, 22, and 29, respectively, and the control group animals were sacrificed on day 29. All animals were euthanised using chloroform anaesthesia. The oesophagus and the stomach of each animal were dissected out and routinely processed for histological studies. Results: There was oedema with haemorrhages in the mucosa of the stomach, and acanthosis, hyperkeratosis, and koilocytic changes were observed in the mucosa of the oesophagus of the groups treated with 40 mg/mL of Calabash chalk suspension. Conclusion: Calabash chalk caused histological changes to the stomach and the oesophagus that may lead to other pathophysiological conditions

Stavudine, an anti‑retroviral drug induces reactive astrocytes in motor cortex of albino mice

Objectives: Anti‑retroviral (ARV) drugs are medications used for the treatment and management of retrovirus infections. Stavudine, one of the commercially available ARVs, is a synthetic ARV agent active against the human immunodeficiency virus type 1. In this study, the effect of stavudine on reactive astrocytes on the motor cortex of albino Wistar mice was investigated. Materials and Methods: Twenty‑four albino mice weighing 30 g on the average were equally assigned into three groups, A, B and C (i.e., eight mice in each group). Group A served as the control, while Groups B and C were the experimental groups. Group B received 0.6 mg/kg of stavudine, while Group C received 1.2 mg/kg of stavudine by orogastric tubes twice a day for 21 days. No treatment was given to the control group, and all the animals received feed and water ad libitum throughout the experimental period. Results: Light microscopic study of the reactive astrocytes in the motor cortex of mice revealed few astrocytes stained black in the control group, Groups B and C revealed a significantly (P < 0.05) higher reactive astrocytes population, with Group C (P < 0.05) having higher reactive astrocytes population compared to Group B. Conclusions: These results revealed that stavudine caused hyperplasia of astrocytes in the motor cortex of albino mice, and this may affect astrocyte activity and consequently impair motor functions. The effect was dose dependent.Key words: Albino mice, astrocytes, motor cortex, stavudin

Gonadal histo-morphologies and serum hormonal milieu in female rats treated with azadirachta indica leaf extract

Background: azadirachta indica is a tree with most of the parts having various medicinal values. It is however popular because of its high potencies, as antimalarial and anti-fertility agents, which the locals still exploit. Objective: We investigated the effect of the methanol leaf extract on the serum levels of the pituitary-gonad hormones and the histo-morphology of the ovary and uterus of adult female rats. Materials and Methods: Eighteen adult female Wistar rats were divided into three groups (A, B and C) of six animals each. Group A was the control group that received distilled water orally, while groups B and C were the experimental groups that received 200mg/kg and 400mg/kg of the extract respectively by oral intubation for fourteen days. The animals were sacrificed on the fifteenth day, and blood was collected from the left ventricles of the hearts and subsequently spurned in heparinized bottles for serum hormonal assay. The ovaries and the uteri were then dissected out and preserved in Bouin’s fluid. Routine haematoxylin and eosin method was used to stain them. Results: There were significant (p<0.0001) lower serum levels of luteinizing hormone (LH) in the treatment groups, especially in the 400mg/kg group, while there were significant (p<0.0001) higher progesterone (PH) levels in the treatment groups. The follicle stimulating hormone (FSH) levels were however not different (p=0.0502) from the control. The histo-morphologic studies revealed no obvious pathological changes in the ovaries and uteri of the treatment groups. Conclusion: 200mg/kg and 400mg/kg of methanol extract of the leaf of A. indica does not have any obvious effect on the histo-morphologies of the ovary and uterus, but showed significant changes in the serum levels of LH and PH of female Wistar rat, implying that the effect of the extract may have been at a level other than these organs of study

Calabash Chalk's Geophagy Affects Gestating Rats' Behavior and the Histomorphology of the Cerebral Cortex

Introduction. Calabash chalk contains heavy metals, and this lead to this study on the effect of this chalk on the behavior and the histomorphology of the cerebral cortex of gestating rats. Material & Methods. 24 female rats were equally divided into 4 groups and were mated at preostrous with the males. The day after mating was designated as day 1 of gestation. On gestation days 7–20, groups 1, 2, 3, and 4 animals were treated with 1 mL of distilled water, and 1 mL (200 mg/kg), 2 mL (400 mg/kg), and 3 mL (600 mg/kg) of calabash chalk suspension, respectively. On pregnancy day 21, behavioral tests using the open field and the light/dark mazes were carried out and the animals subsequently euthanized and their brains were routinely processed. Results. There was no difference in ambulatory activities, but group 4 animals had more (P<0.05) transition frequency and were more averse to the dark in the light and dark field, while sections of the cerebral cortex showed a higher (P<0.05) cellular population, hypertrophied pyramidal cells, and vacuolations in the treatment groups. Conclusion. Calabash chalk may have anxiolytic effect especially at high dose in the light and dark field but not in the open field and can stimulate maternal cerebral cortical cellular changes

Teratogenic Effects of Crude Ethanolic Root Bark and Leaf Extracts of Rauwolfia vomitoria (Apocynaceae) on the Femur of Albino Wistar Rat Fetuses

Introduction. Rauwolfia vomitoria is a plant used as a sedative and in the treatment of psychotic tendency. This study was on the teratogenic effects of its root bark and leaf extracts on Wistar rat’s fetal femurs. Materials and Methods. Twenty-five female rats weighing between 180 and 200 g were divided into 5 groups, of 5 rats each. Group A was the control, while Groups B, C, D, and E were the experimental. The female rats were mated with mature male rats to allow for pregnancy. Groups B and C animals received orally 150 mg/kg each of the root bark and leaf extracts of Rauwolfia vomitoria, respectively, while Groups D and E animals received 250 mg/kg bodyweight each of the root bark and leaf extracts of Rauwolfia vomitoria, respectively, from day 7 to day 11 of gestation. On day 20 of gestation, the rats were sacrificed, the fetuses were examined, and their femurs were dissected out and preserved, decalcified, and routinely processed using the Haematoxylin and Eosin staining method. Results. Histological observations of the fetal femur bones showed numerous osteoblast and osteoclast, hypertrophy, and hyperplasia of bone cells compared with the control. Conclusion. Ethanolic root bark and leaf extracts of Rauwolfia vomitoria may lead to advanced skeletal development