In vivo striatal dopamine release by M1 muscarinic receptors is induced by activation of protein kinase C.
Islet-activating protein was unilaterally microinjected into rat striatum, and a dialysis cannula was implanted into the same area under anesthesia. After 2 days, various agents were perfused continuously into the striatum through the dialysis membrane, under freely moving conditions. Islet-activating protein (2 micrograms/2 microliters) treatment alone did not change in vivo striatal dopamine (DA) release and metabolism, but completely abolished the increase of striatal DA release evoked in vivo by the M1-selective agonist McN-A-343 (10(-7) M). Forskolin (10(-5) M), an adenylate cyclase activator, increased DA release and showed an additive effect on the DA release evoked by McN-A-343. Polymyxin B, a rather selective inhibitor of protein kinase C, decreased DA release and completely blocked the effect of McN-A-343. These results suggest that in vivo striatal DA release elicited by M1 muscarinic receptors is coupled with interaction with a Go protein and is induced by activation of protein kinase C.
Department of Life Chemistry, Graduate School at Nagatsuta, Tokyo Institute of Technology, Japan.
M
M
Xu
T
T
Yamamoto
T
T
Kato
D008455:(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium Chloride / Q000494:pharmacology; D037361:Adenylate Cyclase Toxin; D000818:Animals; D005576:Colforsin / Q000494:pharmacology; D003342:Corpus Striatum / Q000378:metabolism*; D003956:Dialysis; D004298:Dopamine / Q000378:metabolism*; D004789:Enzyme Activation; D008297:Male; D051379:Mice; D009994:Osmolar Concentration; D037342:Pertussis Toxin; D011112:Polymyxin B / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011976:Receptors, Muscarinic / Q000502:physiology*; D015290:Second Messenger Systems; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D037361:Adenylate Cyclase Toxin; D011976:Receptors, Muscarinic; D010566:Virulence Factors, Bordetella; D005576:Colforsin; D008455:(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium Chloride; D037342:Pertussis Toxin; D011493:Protein Kinase C; D011112:Polymyxin B; D004298:Dopamine