Life SciencesBiochemistryEndocrinologyCell SignalingHormone BiochemistrySignal TransductionEndocrine BiochemistryHormone SecretionAdditive ResponseAdenylate Cyclase RegulationAdenylate Cyclase SignalingAdenylyl Cyclase RegulationEnzyme ActivityEnzyme Activity RegulationMucosal Endocrine FunctionVasoactive Intestinal Peptide Signaling
Human colonic adenylate cyclase has been shown to be sensitive to vasoactive intestinal polypeptide (VIP) and prostaglandins of the E- and F-type. Maximal activation of enzyme activity averaged 200% for VIP and 300-350% for the E-prostaglandins. Both classes of hormones had an additive effect on enzyme activity indicating the existence of two distinct hormone-sensitive adenylate cyclases in human colonic mucosa.