Opiate receptors in neuronal primary cultures.
The occurrence and characteristics of mu-, delta- and kappa-receptors were studied as effects of the respective agonists on forskolin-stimulated accumulation of cAMP in neuronal enriched primary cultures from the cerebral cortex of foetal rats. Morphine or [D-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin (DAGO) were used as mu-receptor agonists. [D-Ala2,D-Leu5]-Enkephalin (DADLE) or [D-Pen2,D-Pen5]-enkephalin (DPDPE) were used as delta-receptor agonists and dynorphin 1-13 (Dyn) or U-50,488H were used as kappa-receptor agonists. In the presence of 10(-8)-10(-5) M morphine or 10(-8)-10(-5) M DAGO, there was a dose-related inhibition of the 10(-5) M forskolin-stimulated accumulation of cAMP. The inhibitory action of morphine or DAGO was reversed by naloxone. In the presence of 10(-9)-10(-6) M DADLE or 10(-9)-10(-6) M DPDPE, there was also a dose-related inhibition of the forskolin-stimulated accumulation of cAMP and a similar result was obtained in the presence of 10(-9)-10(-5) M Dyn or 10(-9)-10(-5) M U-50,488 H. These findings indicate that neurones from the cerebral cortex in culture express mu-, delta- and kappa-receptors, that inhibit the forskolin-stimulated accumulation of cAMP. Administration of 10(-5) M morphine and 10(-6) M DADLE or 10(-6) M DPDPE together, resulted in a non-additive inhibition of the forskolin-stimulated accumulation of cAMP, indicating the presence of both mu- and delta-receptors on the same population of cells.
Eriksson
P S
PS
Institute of Neurobiology, University of Göteborg, Sweden.
Hansson
E
E
Rönnbäck
L
L
D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D020881:Enkephalin, D-Penicillamine (2,5)-; D016308:Enkephalin, Leucine-2-Alanine / Q000494:pharmacology; D004745:Enkephalins / Q000494:pharmacology; D005260:Female; D005333:Fetus / Q000378:metabolism; D009020:Morphine / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects* / Q000378:metabolism; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu
D004745:Enkephalins; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D005576:Colforsin; D016308:Enkephalin, Leucine-2-Alanine; D009020:Morphine; D020881:Enkephalin, D-Penicillamine (2,5)-; D000242:Cyclic AMP