Transcriptional regulation of iNOS by IL-1beta in cultured rat pulmonary artery smooth muscle cells

The enzyme nitric oxide synthase (NOS) catalyzes the synthesis of pulmonary NO which provide protection against injury and disease. In a study of cultured rat pulmonary artery smooth muscle cells (RPASMC), treatment of these cells with interleukin-1beta (IL-1beta) stimulated transcription of intracellular NOS. IL-1beta also caused increases in the activity of the 5'-flanking promoter region of the NOS gene. These increases were sustained when the promoter fragment was not shorter than -242 bp. These results suggest that IL-1beta induces NOS gene expression in RPASMC.