RT Journal Article
SR Electronic
T1 Selectivity of muscarinic antagonists in radioligand and in vivo experiments for the putative M1, M2 and M3 receptors.
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 257
OP 262
VO 242
IS 1
A1 H N Doods
A1 M J Mathy
A1 D Davidesko
A1 K J van Charldorp
A1 A de Jonge
A1 P A van Zwieten
YR 1987
UL http://jpet.aspetjournals.org/content/242/1/257.abstract
AB In the present study we investigated the nature of the muscarinic receptors present in the hippocampus, sympathetic ganglia, atria and salivary glands of the rat. The heterogeneity of the muscarinic receptors was examined both in vivo and in radioligand binding experiments. To study whether the receptors present in the investigated tissues are indeed distinct subtypes we determined the potencies of antagonists in both systems. It is proposed that there are three different binding sites present in hippocampal, atrial and submandibular membranes and we suggest to classify them as M1, M2 and M3, respectively. Both in vivo and in vitro pirenzepine appears to possess high affinity for M1 receptors, whereas 4-diphenylacetoxy-N-methylpiperidine methobromide and dicyclomine show high affinity for both M1 and M3 receptors. AF-DX 116 (11-2[[2-[(diethylamino)methyl]-1-piperidinyl]acetyl]-5, 11-dihydro-6H-pyrido[2,3-b][1,4]benzodiazepine-6-one) displayed high affinity for M2 receptors.