Physiology General a5d03184 Fat in the duodenum lumen A Stimulates gall bladder contraction B Inhibits gall bladder contraction C Inhibits CCK secretion D Releases secretin High-Yield Explanation Products of fat digestion (long chain fatty acids with more 10 carbon atoms) in the duodenum increase the secretion of CCK, the most potent hormone causing gallbladder contraction.