Obstruction of the Common Bile Duct in Experimental Renal Hypertension in Dogs

Abstract

The frequency of arterial hypertension in subchronic atrophy of the liver is very low in relation to what might be expected according to the age-distribution of the patients. The hypothesis was established that a severely damaged liver function may prevent the development of arterial hypertension, or may obviate an already existing hypertension, and that a normal or only slightly inhenced liver function is a necessary condition for the development of hypertension.

Summarizing, it can be said about the results of our experiments that 6 hypertensive dogs (with experimental, rend hypertension according to Goldblatt's method!) -4 having had hypertension of short duration, 2 having had a more prolonged hypertension -displayed a gradual fall of the blood pressure towards or down to the normal, pre-operative values after obstruction of the common bile duct had been established. These blood pressure falls were observed in clogs in good health, which were sufficiently fed.

In one dog biliary cirrhosis with ascites and decreased serum albumin per cent developed after obstructive jaundice for 51 days : the high blood pressure fell in relation to the obstruction of the bile duct and remained at normal values in spite of the fact that the obstruction of the bile duct was later on obviated by cholecystoduodenostomy and in spite of permanent constriction of the left renal artery (this dog had one kidney only).

In one hypertensive clog a sham operation on the common bile duct did not change the high blood pressure, whereas a subsequent obstruction of the common bile duct resulted in a gradual fall of the blood pressure to normal, pre-operative values.

In one normotensive dog the obstruction of the common bile duct produced no material changes of the blood pressure for 28 days after the operation.

The changes of the serum proteins observed -a fall of the serum albumin and a rise of the serum globulin with positive Takata-Ara test -and the development of ascites in 4 out of 6 dogs suggest that a massive influence is exerted on the liver function after complete obstruction of the common bile duct in dogs.

The cause of the fall of the blood pressure after obstruction of the common bile duct in hypertensive dogs is not known. It is not very probable that it should be unspecific, or caused by retention of bile in the blood. The experiments do not exclude the possibility that changes of the liver function may be of pathogenetic importance. Complete obstruction of the common bile duct produces a fall of the serum albumin per cent and a rise of the serum globulin per cent and, in many cases, it also gives rise to ascites.

Further investigations must aim at examining hypertensinogen and the vasodepressor material (VDM) under these experimental conditions