HIGH PLASMA-LEVELS OF ENDOTHELIN-1 AND ATRIAL-NATRIURETIC-PEPTIDE IN PATIENTS WITH ACUTE ISCHEMIC STROKE

The plasma levels of endothelin-1 (ET-1) and atrial natriuretic peptide (ANP) have been measured in 37 patients with acute ischemic stroke, on admission and 3 and 7 days thereafter. The plasma ET-1 levels at the onset of symptoms were about twofold those observed in age-matched normal volunteers (3.5 +/- 2.26 v 1.54 + 0.9 pg/mL, respectively; P <.001). These levels remained significantly elevated during the 7-day study period. The neurologic deficit was assessed daily by Mathew's modified scale (MS). A significant correlation was found between neurologic status on admission and ET-1 plasma values; patients with worse neurologic status (MS < 45 points) had higher ET-1 plasma values than those with better neurologic status (MS > 45 points) (5.4 +/- 2.34 v 3.05 +/- 2.04 pg/mL, respectively, P <.05). The plasma ET-1 values did not correlate either with the site of the infarction or with its primary cause (cardioembolic, lacunar, or atherothrombotic). No significant differences were seen in plasma ET-1 concentrations between patients who eventually died and those who survived the acute event. The plasma ANP were about 18-fold higher in ischemic stroke patients on admission than in controls at admission (110.9 +/- 29.5 v 5.84 +/- 3.96 pg/mL, respectively, P <.01). These values remained significantly elevated on days 3 and 7. There was no correlation between the ANP plasma values and the neurologic status, the site or mechanism of the stroke, or the plasma ET-1 levels. In conclusion, ischemic stroke is associated with marked acute and long-duration increases of ET-1 and ANP. These findings may reflect an enhanced production by damaged endothelial cells within the infarcted tissue and might imply a possible role of ET-1 in the pathogenesis and final outcome of cerebral infarction. The ANP elevation could reflect a vasodilator response to the potent contractile effect of ET-1.