the catecholamine-induced release of [ 3h ] gdp was increased 2 to 3 times in the presence of the unlabeled guanyl nucleotides gtp , guanosine 5'- ( beta , gamma-imino ) triphosphate [ gpp ( nh ) p ] , gdp , and gmp , whereas adenine nucleotides had little effect .
C0018353
gtp
C0018366
gpp ( nh ) p