Which glut transports glucose from intestine to liver
(B) (2) (269-A-K-Jain 5th (416-sembulingam 6th (320-Ganong 23rd)* The glucose is transported by glucose transporter-2 (GLUT-2) In to the interstial space and hence to the blood capillaries* GLUT-4 Is insulin sensitive and is located in cytoplasmic vesicles. It is present in large numbers in muscle fibers and adipose cells* Fructose is absorbed along the concentration gradient by fascilitated diffusion caused by GLUT-4* When 'Na+-glucose carrier" (cotransporter- SGLT-1 is absent or defective, glucose malabsorption occurs which produce severs diarrhea* Glucose and galactose are absorbed from the lumen against concentration gradient by secondary active transport (cotransport with Na+ carrier protein for this cotransport is SGLT-1Glucose transporters in mammals FunctionKm (Mm)aMajor sites of expressionSecondary active transport(Na1- glucose contransport) SGLT 1Absorption of glucose0.1-1.0Small intestine, renal tubulesSGLT2Absorption of glucose1.6Renal tubulesFacilitated diffusion GLUT 1Basal glucose uptake1-2Placenta blood -brain barrier, brain red cells, kidneys, colon many other organsGLUT 2B-cell glucose sensor; transport out of intestinal and renal epithelial cells.12-20B cells of islets. Liver, epithelial cells of small intestine kidneys.GLUT 3Basal glucose uptake<1Brain, placenta, kidneys, many other organsGLUT 4Inulin stimulated glucose uptake5Skeletal and cardiac muscles, adipose tissue, other tissues.GLUT 5Fructose transport1-2Jejunum, spermGLUT 6None-PseudogeneGLUT 7Glucose 6-phosphate transporter in Endoplasmic reticulum Liver? Other tissues* Primary action of Nitric Oxide (NO) in the GIT is -Gastrointestinal smooth muscle relaxation * *Action of NO1. Most important action is the relaxation of smooth muscle, the constant release of NO from endothelial cells produces vasodilatation. NO produces relaxation of GI smooth muscle. Vasodilatation in corpora cavernosa helps in penile erection2. No acts as short lived biological messages by stmulating guanyl cyclase that produce c GMP and c GMP activates protein kinase G.3. NO inhibits platelets adhesion, activation and aggregation4. Recent use in persistent pulmonary hypertension of the newborn5. Nitric oxide also called endothelium derived relaxing factor (EDRF) is formed from amino acid arginine by the action of the enzyme no synthase which is cytosolic ***
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G.I.T.