The prospective double blind pilot study was implemented in nine patients to assess the endothelin-1 levels in traumatic subarachnoid haemorrhage (tSAH) and to compare it with the incidence of vasos- pasms. Four patients had tSAH, two spontaneous subarachnoid haemorrhage (sSAH) after rupture of an aneurysm, one had surgery of a pituitary adenoma and two patients served as controls. The endothelin-1 values were assessed by radioimmunoassay (RIA) and vasospasms by transcranial Doppler examination (TCD). The assembled results provided evidence that the endothelin values are elevated, and vasospasms, the increased flow rate in the median cerebral artery, resp. develop probably as a result of the action of endothelin-1 in tSAH. Its formation is not linked only to breakdown products of blood but is caused also by direct damage of the vascular endothelium by injury.

        Key words: vasospasms, traumatic subarachnoid haemorrhage, endothelin-1, radioimmunoassay