Bile salts, hypotension and obstructive jaundice

We have examined the effects of bile duct ligation on vascular and extravascular smooth muscle responsiveness to noradrenaline and tyramine using isolated rat hindlimb perfusion, and portal vein and vas deferens preparations. Bile duct ligation reduced the contractile responses to noradrenaline of vascular and extravascular smooth muscle. Exposure of smooth muscle to some bile salts caused a reduction in contractility. This effect was dependent upon bile salt type and concentration. These studies in vitro suggest that the reduced total peripheral resistance and hypotension seen in obstructive jaundice cannot be explained by a spasmolytic effect of some of the bile salts on smooth muscle.