Chronic Allium sativum administration alters spontaneous alternation and cyto-architecture of medial prefrontal cortex of adult Wistar rats

Abstract

Intake of herbs and some of their constituents is reported to reduce risks of some diseases, with Allium sativum being one of such. This study was conducted to investigate the effects of Allium sativum extract on the medial prefrontal cortex and neurobehaviour of adult Wistar rats. Twenty-four male Wistar rats were divided into 4 groups (n = 6). Group 1 was the control and received distilled water placebo orally, while groups 2-4 received oral doses of 78 mg/kg, 156 mg/kg and 312 mg/kg Allium sativum extract for 28 days. On day 29, spontaneous alternation behavioural test was carried out, and immediately the rats were anaesthetized (50 mg/kg ketamine hydrochloride IP.) and perfusion-fixed with 10% buffered formalin. The whole brains were removed and the medial prefrontal cortex excised and processed for histomorphologic studies by haematoxylin and eosin, and cresyl fast violet techniques. Neurobehavioural test revealed less spontaneous alternation in 156 mg/kg Allium sativum group, while the prefrontal cortices of the test groups showed hypertrophy, hyperplasia, pyknosis, karyorrhexis, chromatolysis, loss of brain cellular membranes and Nissl substance. The 156 mg/kg Allium sativum group showed altered spontaneous alternation, while cellular pathologic changes were observed in the medial prefrontal cortex of these test groups in a dose dependent sequence.

Keywords: Allium sativum; Medial prefrontal cortex; Neurobehaviour; Histomorphology; Wistar rat