Stimulatory effect of pituitary adenylate-cyclase activating polypeptide (PACAP) and its PACAP type I receptor (PAC1R) on prolactin synthesis in rat pituitary somatolactotroph GH3 cells

► Role of PACAP and its receptor, PAC1R on prolactin synthesis in pituitary somatolactotroph GH3 cells were examined. ► PACAP increased prolactin promoter activity significantly, but less than that by TRH. ► PACAP on prolactin promoter activity was dramatically potentiated to a degree proportional to the amount of PAC1R transfected. ► PAC1R was induced by PACAP itself, but not by TRH.