Assessment of the Effects of Developmental Lead Exposure on the Dopamine System and its Relationship to Lead-Induced Changes in AttentionEPA Grant Number: GF9500814
Title: Assessment of the Effects of Developmental Lead Exposure on the Dopamine System and its Relationship to Lead-Induced Changes in Attention
Investigators: Bayer, Lorna E.
Institution: Cornell University
EPA Project Officer: Michaud, Jayne
Project Period: August 28, 1995 through August 27, 1996
Project Amount: $32,000
RFA: STAR Graduate Fellowships (1995) Recipients Lists
Research Category: Fellowship - Social Sciences , Economics and Decision Sciences , Academic Fellowships
The purpose of this study is to examine the enduring effect of developmental lead exposure on the Dopamine (DA) system, and its relationship to lead-induced changes in attention. The project will be used to help identify lead-induced pharmacological changes in neurochemistry which can cause enduring cognitive dysfunction in children that are exposed to lead at levels comparable to levels associated with most childhood exposure. For this study, rats exposed to lead developmentally will be tested, after blood lead levels return to control values, in order to assess enduring, rather than concurrent effects. The lead-exposed animals will be tested on two tasks assessing attention and distractibility, processes which are dependent on an intact prefrontal DA system. Prior to testing, the animals will be administered compounds that bind selectively to DA receptors, and a dose response correlation will be evaluated to determine if shifts in dose response occur in the lead-exposed animals relative to the controls. A correlation will then be made to determine if alterations in DA receptor sensitivity contribute to the observed performance differences on these tasks. Under this project, a total of eight experiments will be conducted to assess the effects of developmental lead exposure on D1 and D2 DA receptor sensitivity. SKF 81297, a selective D1 agonist, will be used in conjunction with SCH-23390, a D1 antagonist, to assess changes in D1 receptor sensitivity. Similarly, bromocriptine will be used in conjunction with eticlopride to assess changes in D2 receptor sensitivity.