Gastric Emptyng Of Liquids In Rats Subjected To Acute Myocardial Infarction [vaciamiento Gástrico De Líquidos En Ratas Sometidas A Infarto Del Miocardio]

Gastric Emptying (GE) is food transition from the stomach to the upper small intestine. Haemodynamics changes modify gastric emptying and the gastroduodenal motor activity. Myocardial Infarction is a pathological condition in which there are haemodynamics changes. Therefore, the objective of the present investigation was to study the effect of acute myocardial infarction on rat gastric emptying of an isosmotic and inert liquid meal. We conducted a study involving male Wistar rats (varying in body weight from' 220g to 250g), that were allowed to habituate in a laboratory environment and then divided into 3 groups: group INF, rats in which the myocardial infarction was produced by left anterior coronary artery ligation; group SH, rats in which the myocardial infarction was simulated without ligating the anterior coronary artery; and group NA, rats which were not given any anesthesia or surgical procedures. After group constitution, animals were fasted with access to water ad libitum. 24 hours later, the Gastric Retention (GR) of 1.5 ml/100g animal weight of a test meal of 0.9% NaCl plus the marker phenol red was evaluated. GE was indirectly evaluated in conscious animals, through determining the percentage of gastric retention (%GR) of a test meal, measured 10 minutes after orogastric infusion. Results of the present study showed that animals from the INF group presented GR (median=48.0%), significantly higher than the NA group (30.6%) and SH group (36.6%). No statistical difference in GR was observed between the SH and NA groups. Infarcted area, expressed in percentages, in animals of the INF group was 51.3±4.7% (mean SEM, N=17) which not presented correlation with results of GR of the same group (r=-0.05). 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