Somatostatin attenuates the hyperdynamic circulatory state in the gastric mucosa of rats with portal hypertension.
BACKGROUND
Portal hypertensive gastropathy is characterized by a hyperdynamic circulatory state in the gastric mucosa. We assessed the effect of bolus injection of somatostatin on gastric mucosal perfusion in a rat model of portal hypertension. We tested the hypothesis that somatostatin will reduce gastric mucosal perfusion in portal hypertension.


METHODS
Portal hypertension was induced by two-stage portal vein ligation (PVL). Two weeks after PVL significant elevation of portal venous pressure was demonstrated. Gastric mucosal hemodynamic changes were measured by reflectance spectrophotometry, which records the indexes of mucosal hemoglobin oxygen saturation (ISO2) and mucosal hemoglobin concentration (IHB).


RESULTS
After an intravenous bolus of 1 microgram somatostatin significant reductions of ISO2 and IHB were demonstrated in the rats with PVL (ISO2, -34 +/- 5%; IHB, -15 +/- 2%) and the controls (ISO2, -26 +/- 4%; IHB, -15 +/- 2%). A dose-response relationship was shown by using 0.01, 0.1, and 1 microgram of somatostatin. Somatostatin did not induce other hemodynamic changes except a transient drop in systemic blood pressure of 8-10%.


CONCLUSIONS
The significant reductions of gastric mucosal ISO2 and IHB by somatostatin support the hypothesis that somatostatin is capable of attenuating the hyperdynamic circulatory state in the gastric mucosa of rats with portal hypertension and may have a beneficial effect on portal hypertensive gastropathy. This hypothesis deserves to be evaluated in clinical studies.
Sung
J J
JJ
Dept. of Medicine, Prince of Wales Hospital, Chinese University of Hong Kong.
Tsui
C P
CP
Li
M K
MK
Leung
F W
FW
D000704:Analysis of Variance; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005753:Gastric Mucosa / Q000098:blood supply / Q000187:drug effects*; D006439:Hemodynamics / Q000187:drug effects*; D006727:Hormone Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D006975:Hypertension, Portal / Q000628:therapy; D010477:Perfusion; D051381:Rats; D017207:Rats, Sprague-Dawley; D013004:Somatostatin / Q000008:administration & dosage / Q000494:pharmacology*; D013053:Spectrophotometry
D006727:Hormone Antagonists; D013004:Somatostatin