Gastric emptying and gastrointestinal transit of liquid in awake rats is delayed after acute myocardial infarction.
The outcome of acute myocardial infarction (AMI) on gastrointestinal motor behavior was assessed in awake rats. Under anesthesia, they were submitted to thoracotomy followed or not by occlusion of the left coronary artery. Next day, they were gavage fed (1.5 ml) with phenol red in 5% glucose solution and sacrificed 10, 20, or 30 min later. Each subset consisted of 7 to 19 animals. Dye recovery in the stomach, proximal, mid, and distal small intestine was obtained by spectrophotometry. Infarcted left ventricle plus septum area was about 48.9 +/- 2.8, 55.1 +/- 6.7, and 54.1 +/- 8.1% (respectively, for 10-, 20-, and 30-min subsets). AMI increased gastric dye retention by 25.5, 51.3, and 65.1% (respectively, for 10-, 20-, and 30-min subsets), while it decreased mid small intestine retention at 30 min (45.3%) as well as distal retention at 10 min (90.5%) and 20 min (90%). A positive correlation (rS = 0.64) was found between infarcted area and gastric retention values at 10 min. AMI also increased (P < 0.05) central venous pressure values in all subsets (3.8 +/- 0.2 vs. -2.1 +/- 1.5, 1.4 +/- 0.1 vs. 0.5 +/- 0.2, and 1.6 +/- 0.4 vs. -0.2 +/- 0.3 cm H2O), while it decreased (P < 0.05) mean arterial pressure (95.0 +/- 2.6 vs. 110.0 +/- 3.9 and 106.0 +/- 2.0 vs. 113.0 +/- 3.0 mm Hg, respectively, at 10 and 30 min), and increased (P < 0.05) the 10-min heart rate values (429.6 +/- 11.3 vs. 374.0 +/- 19.8 bpm). Omeprazole pretreatment did not alter this phenomenon. In another group of rats, cardiac chemoreflex stimulation by i.v. phenylbiguanide increased gastric dye retention by 51.1%. In conclusion, AMI delays the gastric emptying and gastrointestinal transit of liquid in awake rats.
Camurça
Flávio Duarte
FD
Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil.
De Queiroz
Dário Augusto Ferreira
DA
Leal
Paulo Roberto Lacerda
PR
Rodrigues
Cleonísio Leite
CL
Gondim
Francisco Assis Aquino
FA
Da Graça
José Ronaldo Vasconcelos
JR
Rola
Francisco Hélio
FH
Nobre e Souza
Miguel Angelo
MA
dos Santos
Armenio Aguiar
AA
D000818:Animals; D005502:Food; D005746:Gastric Emptying / Q000502:physiology*; D005767:Gastrointestinal Diseases / Q000209:etiology / Q000503:physiopathology*; D005772:Gastrointestinal Transit / Q000502:physiology*; D008297:Male; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology*; D051381:Rats; D014851:Wakefulness