Catecholamine Contents of Different Region of Adult Rat Brain Are Altered Following Short and Long-term Exposures to Pb+2

Abstract

Catecholamine is a group of neurotransmitters that is believed to be responsible for the normal function of animal brain. Physiological and behavioral changes of human body have been reported due to the damage of the brain function following lead exposure. Due to the assumption of lead disposal in brain tissue with two year for its half-life, which results in alteration of brain function, we investigated the ability of lead to change the brain catecholamines during short and long-term studies. Rats were exposed daily with varying amounts of lead and catecholamine contents of cerebellum, mid-brain and brain cortex were determined. Acute peritoneal administration of single dose of lead as lead acetate (260 µmol/Kg) after 2 h reduced (p < 0.05) the catecholamine levels of cerebellum, mid-brain and cortex part by 34.9%, 35.44% and 23.8%, respectively. The extension of experiment time to 5 h, significant (p < 0.05) reductions in catecholamine levels of mentioned regions of brain by 32.35%, 12.35% and 19.3% were seen respectively. Daily intraperitoneal administration of 10 µmol/Kg lead for 30 and 60 days reduced catecholamines levels of cerebellum (22.22% and 30.44%), mid-brain (12.48% and 26.27%) and brain cortex (11.58% and 26.7%) respectively. It might be concluded that brain dysfunction in lead intoxicated rat occurred through the reduction in the catecholamine levels of different parts of brain. Lead might be therefore considered as a probable factor in causing neurological disease in lead exposed man.