using a competitive enzyme-linked immunosorbent assay , we have found that the guanine nucleotides gtp and guanosine 5'-o- ( thiotriphosphate ) ( gtp gamma s ) ( but not gdp ) and the beta-adrenergic receptor agonist isoproterenol activate gs in native s49 cell membrane by subunit dissociation .
C0018328
guanine
C0018340
gdp