DETECTION OF ENDOTHELIN 1,2 AND ENDOTHELIN-LIKE IMMUNOREACTANT IN WOUND SURFACE AND PLASMA IN MICE WITH THERMAL-INJURY

Endothelin is a well known vasoconstrictive peptides produced by endot helial cells and has been reported to regulate the systemic circulatio n. The authors investigated changes in endothelin in plasma and the su rface of wounds induced with thermal injury using an experimental ear burn model in mice. At 0, 15, 30, 60, 120 and 180 minutes after therma l injury the plasma endothelin-like immunoreactant levels were 1.50 +/ - 0.21, 1.86 +/- 0.36, 2.81 +/- 0.55, 2.62 +/- 0.27, 1.54 +/- 0.14 and 1.25 +/- 0.19 fmol/ml (N=8), respectively. Endothelin-like immunoreac tant levels in the plasma increased gradually until 30 minutes after t he thermal injury. Endothelin-like immunoreactant content in the ear b efore thermal injury and at 60 minutes after injury were 7.04 +/- 0.64 and 8.61 +/- 1.24 fmol/ear (N=8), respectively. The change in endothe lin- like immunoreactant after thermal injury originated from endothel in 1,2; that is, the endothelin-1,2 content of the burned ear increase d significantly 15 and 60 minutes after thermal injury to 12.52 +/- 0. 68 and 11.58 +/- 1.04 fmol/ear, respectively, compared with 1.78 +/- 0 .91 fmol/ear (N=8) obtained before injury. These results suggested tha t endothelin 1,2 existed in the region of the wound caused by thermal injury.