[Role of platelet serotonin in hyperperistalsis after digestive hemorrhages].

Intestinal transit accelerates during gastroduodenal haemorrhage. To test a personal theory that the reason is to be found in serotonin released by platelets and absorbed by the intestine, the behaviour of serotoninaemia has been studied. This proved to be 1.35-9.7 microgram/l (mean: 4.175 microgram/l; E.S. +/- 1.39) in patients with haematemesis and melena, compared to 0.49-0.9 microgram/l (mean: 0.728 microgram/l; E.S. +/- 0.07) in the controls (p less than 0.001). The increase in circulating serotonin to significant values is probably due to hormone release. This dose not occur in cases of melena alone, probably owing to the organism's high capacity for catabolism.