title: Nitric oxide selectively inhibits adenylyl cyclase isoforms 5 and 6.
abstract: We have previously shown that N18TG2 neuroblastoma cells express the type 6 adenylyl cyclase and that preincubation with nitric oxide (NO) attenuates Gs- and forskolin-stimulated activity. Here we show that this inhibition reflects a direct action of NO on the adenylyl cyclase. Preincubation of N18TG2 cell membranes and insect cell membranes expressing recombinant type 5 and type 6 isoforms with NO donors leads to an inhibition of forskolin-stimulated adenylyl cyclase activity. NO donors do not alter the type 1 (representative of the type 1,3,8 family) or type 2 (representative of the type 2,4, 7 family) isoforms expressed in insect cells, even under conditions of compromised assay conditions or a range of temperatures. Thus, the ability of NO to inhibit adenylyl cyclase stimulation is dependent upon the nature of the isoform present, and appears to represent a unique regulation of the type 5,6 isoform family.
authors.affiliation: E.A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO 63104, USA.
authors.forename: J
authors.initials: J
authors.lastname: Hill
authors.forename: A
authors.initials: A
authors.lastname: Howlett
authors.forename: C
authors.initials: C
authors.lastname: Klein
mesh_terms: D000067956:Adenylyl Cyclase Inhibitors; D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D005576:Colforsin / Q000494:pharmacology; D007527:Isoenzymes / Q000037:antagonists & inhibitors; D009447:Neuroblastoma; D009569:Nitric Oxide / Q000494:pharmacology*; D020030:Nitric Oxide Donors / Q000494:pharmacology*; D009599:Nitroprusside / Q000494:pharmacology; D010396:Penicillamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D026423:S-Nitroso-N-Acetylpenicillamine; D014407:Tumor Cells, Cultured
chemical_list: D000067956:Adenylyl Cyclase Inhibitors; D007527:Isoenzymes; D020030:Nitric Oxide Donors; D009599:Nitroprusside; D005576:Colforsin; D009569:Nitric Oxide; D026423:S-Nitroso-N-Acetylpenicillamine; D010396:Penicillamine