The effect of endothelin 1, a recently discovered vasoconstrictor hormone, on levels of plasma glucose and lipids was investigated in pygmy goats. Endothelin 1 was injected intraperitoneally (1.72 micrograms/kg BW) and blood samples were taken by puncturing the jugular vein immediately before and 60, 150 and 240 min post injection. Endothelin 1 in comparison to vehicle significantly increased plasma glucose and FFA levels, whereas plasma triglycerides were significantly reduced. Thus, beside its vasoconstrictive action, endothelin 1 also has metabolic effects. Whether these effects are directly caused by endothelin 1 or whether they are due to a release of a metabolic hormone, e.g. epinephrine, remains to be investigated.