Opioid-specific recognition sites of the mu- and the delta-type in rat striatum after lesions with kainic acid.
The binding of 3H-dihydromorphine (3H-DHM) and of 3H-D-ala2, D-leu5-enkephalin (3H-DADL), which are regarded as relatively selective ligands for mu- or delta-type opioid receptors, respectively, was estimated in total particulate fraction of the striatum of rats in vitro, either in tissue of rats after striatal chemolesions with kainic acid or in control rats (not operated or saline injected into the striatum). Kainate lesions reduced the Bmax values of 3H-DHM by about 78 - 88% depending on the method of calculation, and of 3H-DADL by greater than 90%. Furthermore they lowered the Kd-values, suggesting an increase in affinity. The results are discussed with regard to recent hypotheses on the structure and function of opioid receptors.
D000818:Animals; D003342:Corpus Striatum / Q000378:metabolism*; D004090:Dihydromorphine / Q000378:metabolism*; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives* / Q000378:metabolism; D016308:Enkephalin, Leucine-2-Alanine; D007608:Kainic Acid / Q000633:toxicity*; D007700:Kinetics; D008297:Male; D009022:Morphine Derivatives / Q000378:metabolism*; D011759:Pyrrolidines / Q000633:toxicity*; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism*; D017465:Receptors, Opioid, delta; D017450:Receptors, Opioid, mu
D009022:Morphine Derivatives; D011759:Pyrrolidines; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D017450:Receptors, Opioid, mu; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine; D004090:Dihydromorphine; D007608:Kainic Acid