the early 2 -- 3-fold increase in cyclic amp accumulation elicited by adenosine and 2-chloroadenosine , an adenosine deaminase-resistant analogue , could not be correlated to similar effects on the adenylate cyclase activity of disrupted cell preparations , but rather to the competitive inhibition of the low km ( 0.17 mum ) cyclic amp phosphodiesterase .
C0001443
adenosine
C0000275
2-chloroadenosine