Background: Plants such as Cnestis ferruginea and Rauwolfia vomitoria, are a great source of medicines especially in traditional medicine, which are useful in the treatment of diseases, e.g. depression.
Objectives: The effects of aqueous extract of Cnestis ferruginea and ethanolic extract of Rauwolfia vomitoria on blood chemistry and GABAergic neurotransmission were investigated.
Methods: Twenty Sprague Dawley rats (164 +/- 13g) were divided equally into 5 groups, A-E. Psychosis was induced by orally administering 25 mg ketamine hydrochloride/kg body weight for 14 days. On the 15th day, groups B and C received 1 g/kg and 2 g/kg body weight of aqueous fruit extract of Cnestis ferruginea respectively, groups D and E received 2 g/kg and 4 g/kg body weight of ethanolic root extract of R. vomitoria, while the control, group A received 1 ml saline daily for 7 days. The rats were sacrificed, brain, liver and heart were excised and weighed. Blood was obtained and haematological parameters such as, red blood cell (RBC), white blood cell (WBC), and platelet counts were determined. Serum aspartate amino transferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP) activities, serum albumin, cholesterol and total protein were determined. Brain glutamate, gamma amino butyric acid (GABA) concentrations and glutamate decarboxylase activity (GAD) were assayed.
Results: There was a significant increase (p < 0.01) in serum ALP, ALT activities and serum albumin level in R. vomitoria treated rats, with no significant change in C. ferruginea treated rats compared to control. Brain glutamate level decreased in R. vomitoria treated rats, GABA level and GAD activity increased in both C. ferruginea and R. vomitoria treated rats.
Conclusion: Data of the study indicate that extracts of C. ferruginea and R. vomitoria affected certain haematological and blood chemistry indices and mediated the enhancement in GABAergic neurotransmission.