Adiponectin and the regulation of gastric content volume in the newborn rat  

作　　者：Huanhuan Wang Paul Esemu-Ezewu Jingyi Pan Julijana Ivanovska Estelle B Gauda Jaques Belik 

机构地区：[1]Department of Paediatrics,The Hospital for Sick Children,Toronto M5G 1X8,Ontario,Canada [2]Department of Paediatrics and Physiology,The Hospital for Sick Children,Toronto M5G 1X8,Ontario,Canada

出　　处：《World Journal of Gastroenterology》2021年第33期5566-5574,共9页世界胃肠病学杂志（英文版）

基　　金：Supported by Canadian Institutes of Health Research,No.CIA310955.

摘　　要：BACKGROUND Oral intake is dependent on the gastric ability to accommodate the food bolus.Comparatively,neonates have a smaller gastric capacity than adults and this may limit the volume of their milk intake.Yet,we previously reported that the newborn rat gastric milk volume is greatest after birth and,when normalized to body weight,decreases with postnatal age.Such age-dependent changes are not the result of intake differences,but greater gastric accommodation and reduced emptying rate.AIM Hypothesizing that breastmilk-derived adiponectin is the factor regulating gastric accommodation in neonates,we comparatively evaluated its effects on the rat fundic muscle tone at different postnatal ages.METHODS In freshly dispersed smooth muscle cells(SMC),we measured the adiponectin effect on the carbachol-induced length changes.RESULTS Adiponectin significantly reduced the carbachol-stimulated SMC shortening independently of age.In the presence of the inhibitor iberiotoxin,the adiponectin effect on SMC shortening was suppressed,suggesting that it is mediated via largeconductance Ca^(2+)sensitive K^(+)channel activation.Lastly,we comparatively measured the newborn rat gastric milk curd adiponectin content in one-and twoweek-old rats and found a 50%lower value in the latter.CONCLUSION Adiponectin,a major component of breastmilk,downregulates fundic smooth muscle contraction potential,thus facilitating gastric volume accommodation.This rodent’s adaptive response maximizes breastmilk intake volume after birth.

关 键 词：Gastric emptying FUNDUS Smooth muscle BREASTMILK Potassium channel Development 

分 类 号：R151.1[医药卫生—营养与食品卫生学]