Haematology, serum biochemistry and histopathological findings associated with sub-chronic administration of methanol leaf extract of Pterocarpus santalinoides DC in albino rats

The effects of sub-chronic administration of Pterocarpus santalinoides methanol leaf extract (PSME) on haematology, serum biochemistry and histology of albino rats were evaluated. Twenty female albino rats, randomly assigned into four groups (A-D) of five rats each, were used for the study. Groups A-C were treated orally with 500, 250 and 50 mg/kg PSME, respectively, while Group D was given distilled water as placebo at the dose of 10 ml/kg (untreated control). Treatment was done daily for 3 months after which blood samples were collected for haematology and serum biochemistry.  After blood sample collection, the rats were weighed and humanely euthanized. The liver, kidneys, heart and spleen were eviscerated and weighed, and relative organ weights calculated. Thin slices of the liver and kidneys were processed for histopathology. Results showed no significant (p > 0.05) differences between the groups in all the haematological parameters assayed. The PSME (50 mg/kg) led to significantly (p < 0.05) higher serum albumin level, and at 250 and 50 mg/kg, it led to significantly (p < 0.05) lower serum creatinine level and mild random vacoulation of the hepatocytes. The PSME at all doses used in the study led to significantly (p < 0.05) higher body weights and significantly (p < 0.05) lower relative spleen and heart weights. It also caused moderate hyperaemia of the renal cortex at 500 mg/kg. It was concluded that oral sub-chronic administration of graded doses of methanol leaf extract of P. santalinoides to albino rats is non-toxic. Key words: Pterocarpus santalinoides, methanol extract, sub-chronic toxicity, haematology, serum biochemistry, histopathology.