EXPRESSION OF NICOTINIC ACETYLCHOLINE-RECEPTORS IN THE RAT SUPERIOR CERVICAL-GANGLION ON MESSENGER-RNA AND PROTEIN LEVEL

The expression of nicotinic acetylcholine receptors (nAChR) in the rat superior cervical ganglion was investigated by Western blotting, immu nohistochemistry and non-radioactive in situ hybridization applying pr obes for the alpha 4-1 and beta 2 subunit mRNA. Immunoblot analysis of homogenized ganglia using the anti-nAChR antibody WF6 revealed a labe led protein band of apparent molecular weight of 40 kDa which is typic al for the alpha subunit of nAChRs. Applying double-labeling immunoflu orescence with antibodies against tyrosine hydroxylase, nAChR-like mol ecules were identified in most postganglionic neurons and in a subpopu lation of small intensely fluorescent (SIF) cells. alpha 4-1 and beta 2 subunit mRNAs were detected in all perikarya of postganglionic sympa thetic neurons but not in SIF cells. These results suggest that antibo dies raised against purified Torpedo AChR bind to nAChR in sympathetic ganglia and indicate that alpha 4-1 and beta 2 subunits art constitue nts of nAChRs in sympathetic postganglionic neurons but not of SIF cel ls.