3H-dihydromorphine binding sites in subcellular fractions of rat striatum.
Binding of low concentrations of 3H-dihydromorphine (3H-DHM) that label specifically opiate mu receptors was tested in the whole particulate (P1 + P2), P1 and P2 fractions of rat striatal homogenate. Two subpopulations of 3H-DHM binding sites were revealed by Scatchard analysis in the whole particulate and in P2 fractions: high-affinity sites of KD approx. 0.2 nM, and low-affinity sites of KD approx. 3 nM. In P1 fraction only one population of low-affinity binding sites was present. Assuming that opiate receptors are predominantly located on synaptosomal membranes, it may be concluded that only high affinity 3H-DMH binding sites represent opiate mu receptors.
D000818:Animals; D003342:Corpus Striatum / Q000378:metabolism*; D004090:Dihydromorphine / Q000378:metabolism*; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D009022:Morphine Derivatives / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism*
D009022:Morphine Derivatives; D011957:Receptors, Opioid; D004090:Dihydromorphine