[Cellular immunity in patients with psoriasis]

The angiotensin converting enzyme activity was determined in a dog's plasma in the course of an irreversible hemorrhagic shock development. A statistically significant increase of the angiotensin converting enzyme activity in the plasma was found after one hour and two hours' duration of posthemorrhagic hypotension. After one hour and two hours' duration of posthemorrhagic hypotension the plasma angiotensin converting activity was higher by 29% and 33%, respectively, compared with the control levels determined in the normotensive period. After three hours' duration of posthemorrhagic hypotension the plasma activity of the angiotension converting activity was even more evident. In these conditions the plasma enzyme activity was increased by 71% compared to the control levels. The results obtained indicate the possibility that certain changes occur at the endothelial level of pulmonary blood vessels during the hemorrhagic shock development. These changes suggest an intense angiotensin converting enzyme release into the systemic circulation. The results of this investigation are a contribution to a better understanding of the renin-angiotensin system in shock conditions.