Effect of focal cerebral ischaemia on modulatory neurotransmitter receptors in the rat brain: an autoradiographic study.
Neurotransmission is strongly affected after ischaemic insult. It is postulated that modulatory neurotransmitter systems and their receptors play a role in experience-dependent and restoration plasticity. In this study, muscarinic cholinergic, serotonergic 5-HT(2A/2C), dopaminergic D(1) and noradrenergic beta(1) receptors were examined after focal cerebral ischaemia in different brain regions, using quantitative in vitro autoradiography. There were six evaluated time points: 4h, 1, 4, 7, 28 and 60 days after the insult. Rats received unilateral ischaemic lesions through photo-thrombosis in the primary somatosensory cortex. In the lesion core, 5-HT(2A/2C), D(1) and beta(1) receptor binding values return to control levels 28 days after displaying initial decreases, while muscarinic binding remains very low, at 30% of controls. From 4h to 60 days post-stroke no changes are observed in the perilesional tissue. In contrast, in remote brain regions, a bilateral increase of serotonergic 5-HT(2A/2C) receptor binding in the somatosensory cortex at the striatum level is observed after 4h and after 7 days post-stroke. In addition, a bilateral decrease of muscarinic cholinergic receptor binding in the hippocampus is observed at each time point examined. This study points to a complex and remote reaction of modulatory systems in response to ischaemic lesions.
Rogozinska
Karolina
K
Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, 3 Pasteura Street, 02-093 Warsaw, Poland.
Skangiel-Kramska
Jolanta
J
D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D011950:Receptors, Cholinergic / Q000378:metabolism*; D011954:Receptors, Dopamine / Q000378:metabolism*; D017981:Receptors, Neurotransmitter / Q000378:metabolism; D011985:Receptors, Serotonin / Q000378:metabolism*
D011950:Receptors, Cholinergic; D011954:Receptors, Dopamine; D017981:Receptors, Neurotransmitter; D011985:Receptors, Serotonin