Endogenous opioid peptides system in haemorrhagic shock--central cardiovascular regulation

Haemorrhagic hypotension is accompanied by an increase in endogenous opioid system activity, however, its significance is not fully recognised. Therefore, the role of endogenous opioid peptides in the central cardiovascular regulation in haemorrhagic shock was reviewed. Complex central opioid mechanisms play an essential role in regulation of cardiovascular centre function in haemorrhagic hypotension since activation of mu and blockade of delta 1 opioid receptors inhibit the initiation of sympathoinhibitory phase of regulation, while activation of kappa receptors blocks the compensatory cardiovascular responses to haemorrhage. Evidences indicate that central nitrergic and glucocorticoid mechanisms are involved in endogenous opioids action.