[The effect of opiate receptor agonists on the blood circulation in rats with hemorrhagic shock]

The effect of intravenous infusion of agonists of mu-(DAGO) and delta-(DADL, DAAE) opiate receptors on mean arterial pressure and heart rate was studied in experiments on rats with dosed blood loss of up to 30% of calculated blood volume. Stimulation of mu-opiate receptors inhibited the drop of mean arterial pressure in hemorrhagic shock, whereas stimulation of delta-opiate receptors failed to produce such an effect. Preliminary injection of naloxone blocked the effects of mu-receptor stimulation.