Norepinephrine increases cyclic GMP in astrocytes by a mechanism dependent on nitric oxide synthesis.
Norepinephrine induces a rapid and concentration-dependent rise (EC50 = 1.21 +/- 0.33 microM) in cyclic GMP levels in astrocyte-enriched cultures from rat brain. The response is partially mediated by alpha 1-adrenoceptors since a marked inhibition is observed in the presence of prazosin while the beta-antagonist propranolol shows a smaller effect and the alpha 2-antagonist yohimbine is ineffective. L-NG-methylarginine, an inhibitor of nitric oxide synthesis from L-arginine, blocks the norepinephrine-induced cyclic GMP accumulation. This effect is reversed by L-arginine.
Agulló
L
L
Instituto de Biología Fundamental V. Villar Palasi, Universidad Autónoma de Barcelona, Spain.
García
A
A
D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism*; D001921:Brain / Q000166:cytology / Q000378:metabolism; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000096:biosynthesis*; D007424:Intracellular Fluid / Q000378:metabolism; D007700:Kinetics; D009566:Nitrates / Q000378:metabolism*; D017942:Nitric Acid; D009569:Nitric Oxide / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D009566:Nitrates; D009569:Nitric Oxide; D017942:Nitric Acid; D006152:Cyclic GMP; D009638:Norepinephrine