Progesterone may impair colonic smooth muscle contraction through response to receptor G-protein-dependent agonists (e.g., cholecystokinin and acetylcholine) and in response to the direct G-protein activator guanosine-5ction through response to receptor G-protein-dependent agonists (e.g., cholecyssterone is a contributing factor of chronic constipation [24,25,26]. The gene discussed is CCK; the disease is Chronic constipation.