Properties and distribution of muscarinic cholinergic receptors in rat striatal micropunched tissue homogenates.
The properties of muscarinic receptors in rat striatal micropunched tissue homogenates were studied with a binding technique using [3H]quinuclidinyl benzilate (QNB) as ligand. Among the agonists, oxotremorine was the most potent inhibitor (ID50 value, 2.20 X 10(-5) M), followed by pilocarpine, acetylcholine, carbachol and bethanechol. No marked differences were found between the binding properties of QNB in the micropunched tissue homogenates and membrane fractions. Therefore, the detailed distribution of muscarinic receptors in the striatum was examined using the micropunched tissue homogenates. High levels of QNB binding in the striatum were found at dorso-lateral sites and low levels in the center regions of the striatum. The technique presented here for studying small regions of the striatum should be useful in further studies of the function of cholinergic neurons.
D000818:Animals; D001921:Brain / Q000378:metabolism*; D001931:Brain Mapping; D002474:Cell-Free System; D002794:Choline / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D011812:Quinuclidines / Q000378:metabolism*; D011813:Quinuclidinyl Benzilate / Q000378:metabolism*; D051381:Rats; D011950:Receptors, Cholinergic / Q000378:metabolism*; D011976:Receptors, Muscarinic / Q000378:metabolism*
D011812:Quinuclidines; D011950:Receptors, Cholinergic; D011976:Receptors, Muscarinic; D011813:Quinuclidinyl Benzilate; D002794:Choline