Adaptation to low-protein diet increases inhibition of gastric emptying by CCK.
Chronic nutritional disorders such as protein malnutrition are associated with delayed gastric emptying and increased postprandial cholecystokinin (CCK) levels. This study investigated the mechanisms involved in gastric emptying adaptation to low-protein diet. Two groups of 12 rats were adapted to a low-protein (LPD) or standard diet (SD) for 3 weeks. As compared to rats fed a SD, in rats adapted to a LPD gastric emptying was delayed, whereas postprandial CCK levels were increased. LPD enhanced antral muscle contractile response to CCK and cerulein without altering response to acetylcholine. This increased contractility was associated with up-regulation of CCK-A receptor mRNA levels in antral muscle. Our data suggest that modulation of gastric emptying after adaptation to a low-protein diet involves up-regulation of both CCK-A receptors and CCK-induced contraction of antral smooth muscle.
Leray
Véronique
V
Centre de Recherche en Nutrition Humaine, INSERM U539, Hôtel Dieu, 44093 Nantes, France.
Segain
Jean-Pierre
JP
Cherbut
Christine
C
Galmiche
Jean-Paul
JP
D000222:Adaptation, Physiological; D000818:Animals; D001835:Body Weight; D002766:Cholecystokinin / Q000037:antagonists & inhibitors* / Q000378:metabolism / Q000494:pharmacology; D018753:Diet, Protein-Restricted; D004044:Dietary Proteins / Q000008:administration & dosage* / Q000378:metabolism; D005746:Gastric Emptying / Q000187:drug effects*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D012333:RNA, Messenger / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D011949:Receptors, Cholecystokinin / Q000187:drug effects / Q000378:metabolism; D013997:Time Factors
D004044:Dietary Proteins; D012333:RNA, Messenger; D011949:Receptors, Cholecystokinin; D002766:Cholecystokinin