[Hemodynamics as affected by delta-sleep-inducing peptide].

The study was performed on 20 male rabbits. The effect of intravenous delta-sleep-inducing peptide (DSIP), 60 nmol/kg in 5 ml of saline, on central hemodynamic parameters was studied in 11 experiments. Nine rabbits formed the control group. Two heterodirectional responses of the heart and vessels occurred in the animals given DSIP, which made them divide into 2 groups: those with a predominantly cardiac type of hemodynamic responses (n = 5) and animals with a predominantly vascular type of hemodynamic responses (n = 6). The results of the studies showed that DSIP affected central hemodynamics of intact animals; a direct action of DSIP on the vascular tone and permeability as well as on myocardial contractility cannot be excluded. The changes in hemodynamic parameters were, however, within the physiological normal range.