[Effect of reperfusion after local ischaemia on the M receptor density in rat brains].
OBJECTIVE
To study the dynamic changes in the density of muscarinic acetylcholine receptor in different areas of rat brains during reperfusion after local ischaemia.


METHODS
The rat cerebral focal ischemia/reperfusion model after middle cerebral artery occlusion was made by the intraluminal suture method. Using 3H-QNB as radioligand, after binding with M receptor on the brain slice of the rat model, the brain samples were exposed on the hypersensitive film [H-3] to complete autoradiography, and the density of M receptor in different areas on the film of autoradiography was measured.


RESULTS
There were no changes in the M receptor density in 2 hours' ischaemia group and 2 hours' reperfusion group, M receptor densities in the area of occipital cortex (OC) and temporal cortex (TC) were observed to decrease significantly in 8 hours' reperfusion group, but the degree of decrease was lower than 24 hours' and 72 hours' reperfusion groups, there was significant decrease in the density of M receptor in the areas of caudate putamen (CP), frontal cortex (FC), TC, OC of the 24 hours' and 72 hours' reperfusion groups and no difference was found between these two groups, and the imaging of M receptor in the domains with decreased receptor was obvious.


CONCLUSIONS
The quantity of M receptor did not change right after ischaemia or reperfusion. It decreased gradually after an interval of time; Imaging of the M receptor could assess the changes of the density of viable cholinergic neurons and be a marker of diagnosis, therapy, and prognosis of brain ischaemia.
Xu
L
L
Department of Nuclear Medicine, PUMC Hospital, CAMS and PUMC, Beijing 100730, China. davidxuly@sina.com
Wang
S
S
Guo
Y
Y
Liu
S
S
Liu
D
D
D000818:Animals; D001345:Autoradiography; D002545:Brain Ischemia / Q000378:metabolism*; D005260:Female; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D011976:Receptors, Muscarinic / Q000378:metabolism*; D015427:Reperfusion Injury / Q000378:metabolism*; D013997:Time Factors
D011976:Receptors, Muscarinic