Sympathetic regulation of heart rhythm under the effect of delta sleep peptide and its deficiency

: In acute experiments on 16 rabbits we've studied effects of delta-sleep peptide and its deficiency on the irritation of the stellate ganglion. It has been revealed, that peptide injection (60 nM/kg) produces lowered positive chronotropic effect and elongated response development during irritation of this ganglion. Administration of antiserum to delta-sleep peptide (T = 1:3000) causes opposite effect: enhances sympathetic response during irritation of the stellate ganglion. Thus, delta-sleep peptide promoted lowered sympathetic influences on the heart.