Distribution of NADPH-diaphorase Activity in the Feline Laryngeal Mucosa

Abstract
We studied nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase activity in the feline laryngeal mucosa using a histochemical technique in an effort to clarify the role of nitric oxide (NO) in the larynx. Many NADPH-diaphorase-positive nerve fibres were distributed around the blood vessels and the laryngeal glands. The majority of neuronal cells in the intralaryngeal ganglia were NADPH-diaphorase-positive. It is likely that NADPH-diaphorase-positive nerve fibres around the blood vessels and glands in the laryngeal mucosa originate from the intralaryngeal ganglia, and that NO regulates circulation and secretion in the larynx.