Changes in lung levels of TNF-α in rats administered saline or ET.

Animals were administered saline (control, open circles) or ET (5 mg/kg, closed circles). Lung tissue was obtained from rats and homogenized in HEPES buffer. After centrifugation of lung homogenate, the supernatant was assayed using a rat TNF-α enzyme-linked immunosorbent assay kit. Lung levels of TNF-α were determined at the indicated time points after the administration of saline or ET. Pre indicates the time just before ET administration. Data are expressed as means ± SD of 4 animals. *P < .01 versus control.