GASTROINTESTINAL MYOELECTRIC ACTIVITY FOLLOWING ABDOMINAL OPERATIONS IN THE OPOSSUM

Gastrointestinal myoelectric activity of the opossum, both in fasting and fed states, was studied after abdominal operations. Five different procedures were performed: a 5-min, a 1-h, and a 3-h laparotomy with intestinal handling, enteroenterostomy and gastrojejunostomy. Electromyographic recordings from the stomach, duodenum, jejunum, ileum and sphincter of Oddi were obtained from unanesthesized animals. A normal fasting pattern after abdominal operations was observed from immediately after surgery to the 5th postoperative day and depended on the type and duration of the surgical procedure. A fed pattern did not occur in the experiments in which food was instilled before the appearance of the myoelectric migrating complex. A normal fed pattern was observed after the myoelectric migrating complex appearance in all but 2 experiments, 1 of which occurred in an animal with an intra-abdominal abscess.