Effect of anti-rat-liver rabbit immune serum on the local circulatory reactions of the rat liver.

The effect of anti-rat-liver rabbit immune serum was studied on liver blood flow and on the reaction to vasoactive substances of the hepatic blood vessels. Male rats weighing 250 to 300 g were anaesthetized with pentobarbital. The femoral artery, the femoral vein and the portal vein were cannulated. Blood pressure was continuously registered in the femoral artery. A thin thermoelement was placed into the liver and in one of experimental groups into the kidney as well, in order to measure the local blood flow. On a single intravenous administration of immune serum, systemic blood pressure, and the local blood flow of the liver and kidney decreased significantly. The decrease was more marked in the kidney than in the liver. The circulatory response so obtained was general and it was not localized to the liver. Arterial blood pressure was unchanged after intravenous pretreatment with 0.5 ml/100 g of immune serum daily for 3 days, but the portal blood pressure decreased. The hepatic local vasoconstriction induced by vasopressin administered into the portal vein was less important than in the control group. The hepatic local circulatory response to noradrenaline and isoproterenol administered into the portal vein was similar in normal and immune serum treated animals. Although immune serum pretreatment caused histological changes in the hepatic blood vessels and reduced portal pressure, it did not affect the adrenergic regulation of hepatic local blood flow, but decreased the sensitivity to vasopressin.