Effect of Postnatal Lead Exposure on the Male Rats Cerebellum: Histological and Behavioral Evaluation

Acute or chronic lead poisoning in animals and humans is well documented. Moreover developing brain appears to be especially vulnerable to lead neurotoxicity, and the cerebellum has been described as a favorable target for lead poisoning. The aim of present study was to evaluate the effects of neonatal lead exposure (postnatal period of cerebellar development) on the motor behavior and cerebellar cortex in male rats. In this study, new born male rats were randomly divided into two groups: Control (n=10) and lead exposure groups (n=10). Rat pups in lead exposure group received 8 mg/kg lead acetate intraperitoneally daily for 21 days. Behavioral studies including rotarod and open field tests were performed in postnatal days 31–33 (PD) and histological study was performed after completion of behavioral measurements in postnatal day 33. Result of the present work indicated that lead could impair rotarod performance in sessions 1, 2 (P<0.01) and in sessions 4, 6 (P<0.05). Also, open field test demonstrated that number of crossing and rearing significantly decreased in lead exposure group as compared to control group (P<0.05). Histological analysis also indicated that number of purkinje cells significantly reduced in lead treated group as compared to control group (P=0.001). These results suggested that chronic postnatal lead exposure had toxic effect on the cerebellum and can induce dysfunctions in motor and exploratory behaviors.