Transcription of the exon 1f/i multi promoter cluster of neuronal nitric oxide synthase is dynamically upregulated by retinoic acid in a cell specific manner

Changes of neuronal NO-synthase (nNOS) expression have been linked to several human gastrointestinal disorders such as achalasia, gastroparesis and IHPS. 9 distinct first exons (1a–1i) of the nNOS gene, driven by separate promoters, exists, showing site specific expression profiles in the human gastrointestinal tract. We have previously shown that nNOS exon 1c expression is significantly decreased in patients with IHPS, whereas nNOS exon 1f is upregulated. Pharmacological stimulation of nNOS expression is a potential treatment option for several gastrointestinal disorders. Therefore, the aim of this study was to…