Hemodynamic changes in post-suspension rats during gradual hemorrhage

We examined the changes of hemodynamic parameters in nembutal-anesthetized rats during gradual hemorrhage (2 ml/100 g body weight during 30 min). In control rats blood pressure began to decline starting from 3rd min of bleeding and from 5th min it was accompanied by cardiac deceleration. Hindlimb vascular resistance was only slightly increased up to 15th min (by 20-30%) and then began to grow drastically. Less prominent changes of hemodynamics were observed in post-suspension rats. The results indicate that when activity of sympathetic nervous system is blunted with anesthetic post-suspension rats demonstrate higher hemodynamic stability during acute hemorrhage.