Stimulation of adenylate cyclase in the heart of Aplysia californica by biogenic amines.
The effects of serotonin (5-HT), dopamine (DA), several peptides including FMRFamide and arginine vasotocin, the diterpene forskolin and Ca2+ were examined on adenylate cyclase in a particulate fraction from hearts of Aplysia californica. Enzyme activity was stimulated 6-7-fold by 5-HT (EC50, 1 microM) in the presence of GTP. Several 5-HT analogs particularly 5-methoxytryptamine and 5-methoxy-N-N-dimethyltryptamine were also active. The stimulatory action of 5-HT was antagonized by the 5-HT receptor blockers methergoline and metitepine and by the DA receptor blocker chlorpromazine. Dopamine had weak stimulatory action (EC50, 10 microM) and an efficacy relative to that of 5-HT of 0.3. The action of DA was antagonized by chloropromazine and metitepine. Several peptides including FMRFamide and arginine vasotocin had no effect on adenylate cyclase when tested over the concentration range 0.1-100 microM. The enzyme was stimulated 6-fold by the diterpene forskolin (EC50, 2 microM). 5-HT-stimulated activity was strongly inhibited by Ca2+. Calmodulin had no action on the enzyme in the presence of Ca2+.
Drummond
G I
GI
Wernham
S
S
Lukowiak
K
K
D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D001048:Aplysia / Q000187:drug effects / Q000201:enzymology*; D001679:Biogenic Amines / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology; D002147:Calmodulin / Q000494:pharmacology; D005576:Colforsin; D004224:Diterpenes / Q000494:pharmacology; D004298:Dopamine / Q000494:pharmacology; D006150:Guanine Nucleotides / Q000494:pharmacology; D066298:In Vitro Techniques; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D009206:Myocardium / Q000201:enzymology; D012701:Serotonin / Q000494:pharmacology; D012969:Sodium Fluoride / Q000494:pharmacology; D013268:Stimulation, Chemical
D000067956:Adenylyl Cyclase Inhibitors; D001679:Biogenic Amines; D002147:Calmodulin; D004224:Diterpenes; D006150:Guanine Nucleotides; D005576:Colforsin; D012701:Serotonin; D008345:Manganese; D012969:Sodium Fluoride; D000262:Adenylyl Cyclases; D008274:Magnesium; D002118:Calcium; D004298:Dopamine