These findings indicate the antiplasmodial efficacy of P. niruri methanol extract, and the localization of this effect in its chloroform fraction.

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Preparations of Crossopteryx febrifuga (Afzel.) Benth. (Rubiaceae) are widely used in Northern Nigeria in the therapeutic management of trypanosomiasis, malaria and painful inflammatory disorders. Previous studies have shown that the methanolic stem bark extract of Crossopteryx febrifuga possesses significant analgesic and anti-inflammatory properties possibly mediated via Non-selective inhibition of cyclo-oxygenase pathways. In the present study, the methanolic stem bark extract of Crossopteryx febrifuga was evaluated against ethanol-and piroxicam-induced ulceration in rats. Histopathological studies of the rat stomach tissues were also carried out in order to determine its safety profile on the gastrointestinal tract (git). The extract (25, 50 and100 mg extract/kg body weight) significantly (P<0.05) and dose-dependently reduced ulcer index induced by ethanol (24 -92%) and piroxicam (81.81-98.60%). Histopathology of the rat stomach tissues from control and extract-treated groups at 25 mg/kg body weight extract showed mild inflammation characterized by infiltration of inflammatory cells, while the extract treated groups at 50 and 100mg/kg body weight and 200 mg misoprostol/kg body weight group showed no obvious lesions. These results showed that the extract had no deleterious effects and was cytoprotective on the gastrointestinal tract (git). It can thus be developed as a safe alternative to conventional non-steroidal anti-inflammatory drugs (NSAIDs) for the management of painful inflammatory disorders.

Alzheimer 's disease (AD) is the most common neurodegenerative disease of this century and the most prevalent cause of dementia among the elderly. 1,2 The disorder is characterized by the presence of extra-neuronal amyloid and tau deposits, dysfunction in cholinergic transmission typified by a progressive decline in levels ABSTRACT Background: Crinum zeylanicum is widely used in the ethno-therapeutic management of folk management of epilepsy, pain, neuropsychiatric, and dementing disorders in Nigeria. The current study was carried out to evaluate the possible mechanism of the memory enhancing the effect of C. zeylanicum extract and alkaloidal rich fraction in Wistar rats. Methods: The effect of Crinum zeylanicum bulb extract (250, 500, and 1000 mg/kg body weight orally), alkaloidal rich fraction (10, 20, and 40 mg/kg body weight p.o.), normal saline (10 ml/kg orally), or Eserine (0.3 mg/kg body weight i.p.) on spatial memory in rats was evaluated using the Y-maze. The blood samples obtained from rats in all treatment groups were evaluated for cholinesterase activities using modified Michelle electrometric method. Results: The extract and the alkaloid significantly (p<0.05) and dose-dependently increased spontaneous alternation behavior of rats in Y-maze. The extract produced 20.00%, 35.55%, and 52.00% inhibition of cholinesterase activity in the blood at 250, 500, and 1000 mg/kg body weight, respectively. The alkaloid produced 56.67%, 62.67%, and 68.67% inhibition of cholinesterase activity in blood at 10, 20, and 40 mg/kg body weight (p.o.). Eserine a standard cholinesterase inhibitor at 0.3 mg/kg body weight produced a significant increase in spontaneous alternation behavior and produced 73.33% inhibition of blood cholinesterase activity. Data obtained from the study showed that the enhanced spontaneous alternation behavior observed in rats treated with the extract, and the alkaloid may be due to facilitation of cholinergic transmission resulting from inhibition of cholinesterase activity. Conclusion: The extract, as well as its partially purified alkaloid, possesses potential that may be employed for therapeutic management of Alzheimer's disease.

The use of β-adrenoceptor blocking agents (β -blockers) in the clinical treatment of cardiovascular disorders and glaucoma are associated with enhancedvigilance, attention, reward, learning and memory. The present study was designed to explore the possible role of Carvedilol, an adrenergic antagonist in ameliorating scopolamineinduced neurotoxicity in rats. Mice were divided into control and treatment groups. Control mice for each test received 10 ml normal saline/kg while the treatment groups (n = 6) received Carvedilol (2.5, 5 and 10 mg/kg orally) and1 mg scopolamine/kg intraperitoneally). One hour after sildenafil and thirty minutes after scopolamine administration orally and intraperitoneally respectively, the animals were assessed for 5 minutes on elevated plus maze, Y-maze and open-field. The parametersmeasured on the EPM were memory acquisition and memory retention latencies with and without scopolamine while spontaneous alternation behaviour was measured in Ymaze. The effect of Carvedilol on locomotion was assessed in mice using open field.Carvedilol significantly (p<0.001) shortened memory acquisition and retrieval latencies in mice with scopolamine-induced cognitive deficit. Carvedilol produced significant (p<0.0001) increase in spontaneous alternation behaviour in both memory intact and memory deficit models. Carvedilol however, had no effect on locomotor activity of mice. The results suggest that Carvedilol enhanced memory acquisition and retrieval in cognitive deficit and cognitive intactmice.It also improved short term memory as indicated by increase in spontaneous alternation behaviour in mice.Carvedilol may therefore be useful in management of dementing disorders such as Alzheimer's disease.