Forskolin activation of adenylate cyclase in mouse parotid membranes.
In mouse parotid membranes forskolin activated adenylate cyclase four-fold; maximal activation of the enzyme occurred with 10 microM forskolin. Activation was not dependent on the guanyl nucleotide GTP nor on the inhibitory guanine nucleotide 5'-0-(2-Thiodiphosphate), GDP beta S. In contrast, stimulation of adenylate cyclase by isoproterenol required GTP and was antagonized by GDP beta S in a dose-dependent manner. These results indicate that the guanyl-binding protein of mouse parotid adenylate cyclase is not a requisite for forskolin activation and lends support for direct interaction of forskolin at the catalytic subunit.
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D005576:Colforsin / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D006153:Guanosine Diphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000494:pharmacology; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D051379:Mice; D010306:Parotid Gland / Q000187:drug effects / Q000201:enzymology*; D013873:Thionucleotides / Q000494:pharmacology
D013873:Thionucleotides; D006153:Guanosine Diphosphate; D005576:Colforsin; C023427:guanosine 5'-O-(2-thiodiphosphate); D006160:Guanosine Triphosphate; D000262:Adenylyl Cyclases; D007545:Isoproterenol