NADPH-diaphorase-positive neurons innervating the rat ovary.

Nerve cell bodies projecting to the ovary were visualized in dorsal root ganglia (DRG) and paravertebral ganglia after application of the retrograde tracer Fluoro-gold to the superior ovarian and plexus nerves. The location of fluorescent cells in sections of ganglia was recorded and subsequently nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry was utilized to locate nitric oxide synthase (NOS) whose presence indicates sites where nitric oxide (NO) can be synthesized. No fluorescent nerve cell bodies in paravertebral ganglia were NADPH-diaphorase-positive. In contrast, numerous Fluoro-gold-labeled nerve cell bodies in DRG at segmental levels T12-L1 were NADPH-diaphorase positive. Thus, many sensory neurons projecting to the ovary contain NOS and presumably release NO. This gaseous messenger molecule may participate in modulation of ovarian function.