<prompt> Insulin secretion isare increased by all except: PGI Nov 2010GastrinSecretinVIPG1P  <response>: Ans: C VIP Ref.Guyton llth968-69; Ganong 24th441, 23rd326 Insulin: Effect of Various Hormones Guyton nth969Gastrointestinal Hormones. A mixture of several important gastrointestinal hormones-gastrin, secretin , cholecystokinin, and gastric inhibitory peptide3 which seems to be the most potent- causes a moderate increase in insulin secretion. These hormones are released in the gastrointestinal tract after a person eats a meal.Other Hormones and the Autonomic Nervous System. Other hormones that either directly increase insulin secretion or potentiate the glucose stimulus for insulin secretion include glucagon, growth hormone, cortisol, and, to a lesser extent, progesterone and estrogen3Table Ganong 23rd326 :Factors affecting insulin secretionStimulatorsInhibitorsGlucoseSomatostatinMannose2-DeoxyglucoseAmino acids leucine, arginine, othersMannoheptuloseIntestinal hormones GIP, GLP- 1 , gastrin, secretin, CCK, others?Qa-Adrenergic stimulators norepinephrine, epinephrineb-Keto acidsb -Adrennergic blockers propranolol StimulatorsInhibitorsAcetylcholineThiazide diureticsGlucagonsGalaninCyclic AMP and various cAMP- generating substanceDiazoxideb-Adrenergic stimulatorsK depletionTheophylinePhenytoin; Microtubule inhibitorsSulfonyl ureasAlloxan; Insulin 