furthermore , we show that drugs which : ( 1 ) elevate cyclic amp levels ( dibutyryl ( db ) cyclic amp ) , ( 2 ) inhibit the breakdown of cyclic amp ( theophylline ) , or ( 3 ) stimulate adenylate cyclase ( isoproterenol and histamine ) all restored suppressor cell activation by m1-a5 cells in which pg synthesis had been blocked by acetylsalicylic acid ( asa ) .
C0001455
cyclic amp
C0012054
dibutyryl