Preliminary studies on the behavioural effects of the methanol extract of Leonotis nepetifolia Linn stem in mice

Background: Leonotis nepetifolia Linn (Lamiaceae) is used in traditional medicine for its calming (tranquilizing) effects. The aim of this study was to determine whether there is any scientific justification for this use. To achieve this purpose, we investigated the behavioural effects of the methanol extract of Leonotis nepetifolia stem (37.5, 75 and 150 mg/kg) in mice.Methods: Acute toxicity studies were carried out on the methanol stem extract of Leonotis nepetifolia to determine the LD50. The behavioural tests employed were diazepam-induced sleep onset and duration, hole board assay for exploratory activity, mouse beam walk assay for motor coordination, and the staircase test for the detection of anxiolytic compounds. Preliminary phytochemical screening was also carried out on the extract.Results: The intraperitoneal LD50 value was found to be 3.8 g/kg. The results showed that the extract significantly prolonged the duration of diazepam-induced sleep at the highest dose (150 mg/kg). There was no observable effect on exploratory activity and motor coordination at the doses tested (37.5, 75 and 150 mg/kg). The extract, however, at 150 mg/kg elicited a significant decrease in the number of rearings in the staircase test, an effect also observed in the group of mice injected with an anxiolytic dose of diazepam. The preliminary phytochemical  screening revealed the presence of alkaloids, saponins, glycosides and   triterpenoids.Conclusion: The results obtained suggest that the crude methanol extract of Leonotis nepetifolia stem possesses some biologically active constituents with potential anxiolytic activity and thus may justify its traditional use as a tranquilizer.Keywords: behavioural; exploratory; Leonotis nepetifolia; motor coordination; anxiolyti

PRELIMINARY STUDIES ON THE BEHAVIOURAL EFFECTS OF THE METHANOL EXTRACT OF LEONOTIS NEPETIFOLIA LINN STEM IN MICE

Background: Leonotis nepetifolia Linn (Lamiaceae) is used in traditional medicine for its calming (tranquilizing) effects. The aim of this study was to determine whether there is any scientific justification for this use. To achieve this purpose, we investigated the behavioural effects of the methanol extract of Leonotis nepetifolia stem (37.5, 75 and 150 mg/kg) in mice. Methods: Acute toxicity studies were carried out on the methanol stem extract of Leonotis nepetifolia to determine the LD50. The behavioural tests employed were diazepam-induced sleep onset and duration, hole board assay for exploratory activity, mouse beam walk assay for motor coordination, and the staircase test for the detection of anxiolytic compounds. Preliminary phytochemical screening was also carried out on the extract. Results: The intraperitoneal LD50 value was found to be 3.8 g/kg. The results showed that the extract significantly prolonged the duration of diazepam-induced sleep at the highest dose (150 mg/kg). There was no observable effect on exploratory activity and motor coordination at the doses tested (37.5, 75 and 150 mg/kg). The extract, however, at 150 mg/kg elicited a significant decrease in the number of rearings in the staircase test, an effect also observed in the group of mice injected with an anxiolytic dose of diazepam. The preliminary phytochemical screening revealed the presence of alkaloids, saponins, glycosides and triterpenoids. Conclusion: The results obtained suggest that the crude methanol extract of Leonotis nepetifolia stem possesses some biologically active constituents with potential anxiolytic activity and thus may justify its traditional use as a tranquilize

Renal impact of sub acute lamivudine-artesunate treatment in wistar rats

Background and objectives: Lamivudine and artesunate are life saving drugs in the treatment of HIV/HBV and malaria respectively, and available data shows artesunate having anti-tumour properties. The concurrent administration of both drugs presents important safety concerns. This study investigated possible effects of lamivudine-artesunate co-administration on renal function and histology in wistar rats. Method: Four groups of rats (n=5) were used in the study with one group as control. Two groups received lamivudine at 20 mgkg-1, with another receiving artesunate at 10 mgkg-1. Artesunate was added to one of the lamivudine groups. While lamivudine treatment was for three weeks, artesunate was introduced only in the last week of the study alone, or in combination with lamivudine. At termination, animals were humanely killed and kidneys harvested, weighed and subjected to H and E stain and observation. Serum urea and electrolytes were also determined. Results: Serum biomarkers and kidney weights did not differ significantly (p>0.05). Various histological changes were observed in the treated groups although these didn’t directly correlate the biomarkers determined. Conclusion: The concurrent use of lamivudine and artesunate appears to be safe within the dose levels used. However caution may be needful when repeated or long term exposure is required. Keywords: artesunate, lamivudine, HIV, HBV, malaria, concurrent drug therap

Anti-seizure activity of the aqueous leaf extract of Solanum nigrum linn (solanaceae) in experimental animals

Background: Solanum nigrum is claimed in traditional medical practice, to be useful in the treatment of epilepsy in some parts of Nigeria. Objectives: To study the anti-convulsant property of the aqueous extract of the leaves of S. nigrum in chicks, mice and rats. Method: Aqueous extracts were administered intraperitoneally, at a pre-treatment time of 30 minutes, at graded doses and animals were challenged with different types of proconvulsants. Results: The aqueous leaf extract produced a significantly (P <0.05) dose dependent protection against electrically-induced seizure in chicks and rats, pentylenetetrazole-induced seizure in mice and rats and picrotoxin-induced seizure in mice and rats. The anti-seizure property of the extract was potentiated by amphetamine. Conclusion: The result obtained in this study suggests that the leaves of this plant may possess anti-convulsant property in chicks, mice and rats