FORSKOLIN DOES NOT AUGMENT THE BRADYKININ RESPONSE OF CANINE VISCERALPOLYMODAL RECEPTORS IN-VITRO

In clarifying the possible involvement of cyclic AMP (cAMP) in prostag landin (PG) E(2)-induced sensitization of the bradykinin response of c anine testicular polymodal receptors, the effects of forskolin. an act ivator of adenylyl cyclase, were studied in the presence and absence o f acetylsalicylic acid (ASA, 550 mu M) which blocks PG production. For skolin (10 mu M) seldom induced discharges in polymodal receptors. An unexpected outcome of this study was that forskolin induced no facilit ation of the bradykinin (0.1 mu M) response, both in the absence and p resence of ASA. A slight yet significant suppression of the bradykinin response was instead observed in the absence of ASA. These results su ggest that intracellular cAMP may be related with PG E(2)-induced sens itization of the bradykinin response through its decrease.