Endothelin-induced long-lasting mesenteric vasoconstriction: a hypothetical mechanism of non-occlusive intestinal infarction.
The in vivo mesenteric vascular effect of the novel, endothelium-derived endogenous polypeptide, endothelin-1 (ET-1) was examined in experiments performed on pentobarbital-anesthetized dogs. Blood supply to a segment of the small bowel was measured simultaneously with an electromagnetic flow probe and computer-assisted thermography which senses flow-dependent infrared irradiation. It was found that close mesenteric arterial injections of ET-1 produced long-lasting flow decreases of considerable magnitude: the single dose of 1 nmol reduced blood flow by nearly 90 percent, and even the minimal single amount of 1 pmol produced statistically significant vasoconstriction. The thermographic analysis proved the homogenous character of these reactions. Unlike vascular responses elicited by most of the known vasoconstrictive agents, the ET-1-induced spastic effects were maintained without a continuous exposure (drug infusion). All features that characterize the spastic ET-1 action qualify the peptide for a hypothetical candidate of mediating the nonocclusive mesenteric ischemic syndrome.
Dóbi
I
I
Department of Cardiovascular Surgery, Semmelweis University Medical School, Budapest, Hungary.
Kékesi
V
V
Tóth
M
M
Juhász-Nagy
S
S
D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D004285:Dogs; D016232:Endothelins / Q000494:pharmacology / Q000502:physiology*; D005260:Female; D007238:Infarction / Q000503:physiopathology*; D007422:Intestines / Q000098:blood supply*; D008297:Male; D008638:Mesenteric Arteries / Q000503:physiopathology*; D013817:Thermography; D014661:Vasoconstriction / Q000187:drug effects
D016232:Endothelins