Endothelin-1 levels in bronchoalveolar lavage fluid (BAL) fluid in sarcoid patients and healthy controls. Endothelin-1 levels were measured by enzyme immunoassay and were corrected by albumin concentration in recovered BAL fluid. The data represent values ± standard error of the mean in both groups. *P < 0.05. Reproduced with permission from Terashita et al. Respirology 2006. © Blackwell Publishing .