Neurotoxicity and oxidative stress induced by gibberellic acid in rats during late pregnancy and early postnatal periods: biochemical and histological changes.

Gibberellic acid (GA(3)) is an endogenous plant growth regulator used worldwide in agriculture; however, little is known about its biochemical and physiological effects on mammals. This study investigated possible neurotoxic effects of GA(3) on the cerebrum and cerebellum of suckling rats. Female Wistar rats were given daily 200 ppm GA(3) in drinking water from the 14th day of pregnancy until day 14 after delivery. Acetylcholinesterase activity in both cerebellum and cerebrum was inhibited after treatment with GA(3). Neurotoxicity was demonstrated by a significant increase in malondialdehyde level and a decrease in the antioxidant enzyme activities of catalase, superoxide dismutase, glutathione peroxidase in the cerebrum and cerebellum of suckling pups. A significant decline of glutathione content and vitamin C was also observed. The biochemical parameters were correlated histologically with an abnormal development of the external granular layer and a loss of Purkinje cells in the cerebellum of GA(3)-treated suckling rats.