Spinal nNOS regulates phrenic motor facilitation by a 5-HT2B receptor- and NADPH oxidase-dependent mechanism.

Highlights: [•] Neuronal nitric oxide synthase is necessary for phrenic long-term facilitation (pLTF) following acute intermittent hypoxia. [•] Episodic spinal NO is sufficient to elicit facilitation of phrenic nerve activity (pMF). [•] NO-induced pMF involves 5-HT2B receptors and spinal NADPH oxidase activity. [ABSTRACT FROM AUTHOR]