in addition to hormones and neurotransmitters , fluoride ion , cholera toxin and guanyl nucleotides ( gtp and gtp analogs such as gtp gamma s and gmp-p ( nh ) p ) also stimulate adenylyl cyclase activity ( perkins , 1974 ; birnbaumer , 1977 ; gill , 1977 ) .
C0018353
gtp
C0079469
gtp