Catecholamine-sensitive adenylate cyclase of caudate nucleus and cerebral cortex. Effects of guanine nucleotides.
1. GTP and GMP-P(NH)P (guanyl-5'-yl imidodiphosphate) were observed to increase the stimulation of neural adenylate cyclase by dopamine (3,4-dihydroxyphenethylamine) and noradrenaline. 2. GMP-P(NH)P had a biphasic effect on the enzyme activity. 3. Preincubation of membranes with GMP-P(NH)P activated the enzyme by a process dependent on time and temperature. Catecholamines increased the speed and the extent of this activation. 4. Membrane fractions contained high- and low-affinity sites for GMP-P(NH)P binding: this binding was due to protein(s) of the membrane preparations. 5. Low-affinity-site binding of GMP-P(NH)P appeared to be related to the stimulatory effect on the adenylate cyclase activity.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D002421:Caudate Nucleus / Q000201:enzymology*; D002540:Cerebral Cortex / Q000201:enzymology*; D004298:Dopamine / Q000494:pharmacology; D004357:Drug Synergism; D006150:Guanine Nucleotides / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000494:pharmacology; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D013268:Stimulation, Chemical; D013347:Subcellular Fractions; D013997:Time Factors
D006150:Guanine Nucleotides; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D000262:Adenylyl Cyclases; D008274:Magnesium; D004298:Dopamine; D009638:Norepinephrine