Different effects of interleukin-1 on reactivity of arterial vessels isolated from various vascular beds in the rabbit.

During septic shock, arterial smooth muscle is thought to be hyporeactive to vasoconstrictors. This hyporeactivity, however, seems to be different from one vascular bed to another. Interleukin-1 (IL-1), which is released during septic shock, might play a role in the different regional vascular responses to norepinephrine. Thus, the aim of the present study was to examine in vitro the effect of IL-1 on the response to norepinephrine of arteries isolated from different territories in the rabbit. Three types of responses were identified: IL-1 decreased NE-induced contraction by 54% in aorta, 42% in carotid artery, 54% in pulmonary artery, and 18% in renal artery; and IL-1 was devoid of significant effect in hepatic and mesenteric arteries; and IL-1 increased NE-induced contraction by 25% in femoral arteries. In conclusion, IL-1 might contribute to the regional blood flow abnormalities during septic shock.