[Influence of ET-1 and ETA receptor blocker (BQ123) on the level of TNF-α in the brain rat].

Unlabelled: Endothelin 1 (ET-1) in addition to the vasoconstriction, also has mitogenic, proinflammatory and proagregation activities. The mediators of inflammatory responses are cytokines, including special role attributed to tumor necrosis factor (TNF-α).

Aim: The aim of this study was to evaluate the effect of ET-1 and its receptor blocker (BQ123) on the level of TNF-α in the brain rat.

Materials And Methods: Experiments were performed on four groups of Wistar-Kyoto rats. Animals were divided into four groups of 8 rats. Group I - control was administered into the tail vein solution of 0.9 % NaCl. Group II - saline followed by ET-1 (3 μg/kg b.w.). Group III - saline followed by BQ123 (1 mg/kg b.w.). Group IV (BQ123/ET-1) - BQ123 (1 mg/kg b.w.) administered 30 min before ET-1 (3 μg/kg b.w.).

Results: Administration of ET-1 at doses of 3 μg/kg b.w. resulted in a statistically significant increase in TNF-α concentrations in brain homogenates compared to the control group (p<0.01). Administration of the ET(A) receptor blocker - BQ123 (1mg/kg b.w.) 30 min before administration of ET-1 significantly decreased in TNF-α concentrations in brain homogenates (p <0.01).

Conclusions: ET-1 is significantly increased in TNF-α levels in brain homogenates, while BQ123 given 30 min before administration of ET-1 caused a significant decrease in TNF-α levels, suggesting that its anti-inflammatory activity.