Effects of sub-chronic in vivo chlorpyrifos exposure on muscarinic receptors and adenylate cyclase of rat striatum
Effects of sub-chronic in vivo chlorpyrifos exposure on muscarinic receptors and adenylate cyclase of rat striatum
复制标题
DOI：
10.1007/s002040100269
复制
发表时间：
2001-10-01
影响因子：
6.1
通讯作者：
Abou-Donia, MB
中科院分区：
文献类型：
--
作者：
Huff, RA;Abu-Qare, AW;Abou-Donia, MB
In this study dosing regimens were designed such that cholinesterase inhibition following exposure to chlorpyrifos was produced in one treatment group. but was absent in the other. The higher dosing regimen inhibited plasma and brain cholinesterase activities by 51 and 70%, respectively, and resulted in decreased [H-3]cis-methyldioxolane ([H-3]CD) binding, which was attributable to a decrease in B-max. No concomitant loss Of [H-3]quinuclidinyl benzilate ([H-3]QNB) binding sites was observed., indicating that the M, muscarinic receptor subtype to which [H-3]CD binds is particularly susceptible to alterations induced by chlorpyrifos treatment. As the M-2 receptor subtype is surmised to be the muscarinic autoreceptor, decreases in this receptor may exacerbate poisoning by organophosphorus agents as a result of decreased ability to terminate synaptic acetylcholine release. The ability of carbachol to inhibit striatal adenylate cyclase, which is an effector molecule associated with the M-2 receptor., was unaltered in chlorpyrifos-treated rats. Decreases in M-2 receptors occurred with the higher dosing regimen, in the absence of any clinical manifestations. Thus, in the absence of overt clinical signs, perturbations of the muscarinic receptor system did occur as a result of sub-chronic chlorpyrifos exposure. Such alterations may contribute to neurological impairments that develop following chronic organophosphorus exposure.
