PLASMA ENDOTHELIN-1 LEVELS DURING ASPHYXIA IN THE FETAL GOAT

The changes in fetal carotid arterial plasma levels of endothelin-1, c atecholamines, PO2, PCO2 and pH were measured after intermittent repet itive umbilical cord occlusion in late gestation pregnant goats (n = 9 ). Endothelin-1 levels increased to 3.58 +/- 0.28 pg/ml immediately af ter the onset of fetal hypoxia, a level significantly higher than the respective values in the control period (p < 0.05). The elevation of f etal plasma endothelin-l levels correlated inversely with carotid arte rial PO2 (r = -0.41, p < 0.05) and pH (r = -0.43, p < 0.05). The resul ts suggest that increased endothelin-l levels may contribute to the ma intenance. of the fetal circulation during fetal asphyxia.