Role of regulatory peptide in pathogenesis of shock

The present study evaluated the pathogenetic roles of three kinds of regulatory peptide. The results showed that (i) plasma endothelin (ET) level elevated significantly in septic shock rats, persistent intravenous drip of low doses ET caused development of shock state in normal rats and the irreversible outcome of light hemorrhagic shock. Furthermore, i. v. administration of specific ET-antiserum was significantly effective to septic shock rats. (ii) Plasma calcitonin gene-related peptide (CGRP) increased by 260% in septic shock rats, i. v. drip of low doses CGRP both in early and late sepsis were effective to shock rats. (iii) Angiotensin-II (ANG-II) contents of heart and aorta increased dramatically both in early and late septic shock, and inhibiting its increase with Captopril in late sepsis significantly improved the shock state, but results were inverse in early sepsis. It could be concluded that ET was one of the most important factors participating in the pathogenesis of shock, CGRP had a compensatory regulatory role in shock and the role of tissue ANG-II was different during different periods of shock.