Changes Of Gastric Emptying After Acute Myocardial Infarction In Awake Rats And Study Of The Mechanism

Objection To investigate the changes of gastric emptying in awake rats after acute myocardial infarction.Methods The male Wistar rats were submitted to thoracotomy followed or not by occlusion of the left coronary artery. After 24 h, AMI(n=12)and sham group(n=9)were gavage fed(l ml)with 99^m-Tc-DTPA labeled test meal, Half gastric emptying time (GET_1/2) and 50 min residual rate were measured by single photon emission computed tomography(SPECT). The rats of AMI group were sacrificed after 50 min. Plasma level of motilin was measured by radioimmunoassay respectively AMI and sham group (n=9) .Results GET_1/2 was significantly increased from (16.0±4.0) min in sham group to (23.1±4.7) min in AMI group (P<0.01), 50 min residual rate was significantly increased from (18.1±3.3 ) % in sham group to(27.6±4.5) % in AMI group (P<0.01). Infarction area of AMI group was (52.1±4.1) %, a positive correlation was found between infarction area and 50 min residual rate (r=0.620, P=0.031). The plasma motilin of AMI group and sham group were (81.5±17.6) vs (103.8+24.9) ng/L,motilin was significantly reduced(P<0.01).Conclusion AMI delays the gastric emptying in awake rats, there was positive correlation between infarction area and residual rate.