title: Photoendocrine signal transduction in pineal photoreceptors of the trout. Role of cGMP and nitric oxide.
abstract: This study describes the presence and distribution of cGMP-immunoreactivity and of the nitric oxide (NO) synthesizing enzyme, NO synthase (NOS), as demonstrated by use of the NADPH-diaphorase technique in directly light sensitive pineal organ of the trout. Cyclic GMP immunohistochemistry revealed immunoreactivity in pineal photoreceptor cells that were identified by double-labeling with S-antigen, whereas NADPH-positive structures were located adjacent to these photoreceptor cells. Since NO is known to stimulate synthesis of cGMP, these results indicate a role for NO in pineal function, e.g. in cGMP related events in the phototransduction process as well as in the light-dark control of melatonin synthesis.
authors.affiliation: Max-Planck-Institute for Physiological and Clinical Research, W.G. Kerckhoff-Institute, Bad Nauheim, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Zipfel
authors.forename: H A
authors.initials: HA
authors.lastname: Schmid
authors.forename: H
authors.initials: H
authors.lastname: Meissl
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D006152:Cyclic GMP / Q000502:physiology*; D003624:Darkness; D008058:Dihydrolipoamide Dehydrogenase / Q000378:metabolism; D007150:Immunohistochemistry; D008027:Light; D008550:Melatonin / Q000096:biosynthesis*; D009249:NADP / Q000032:analysis; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D009924:Organ Culture Techniques; D010396:Penicillamine / Q000031:analogs & derivatives / Q000494:pharmacology; D020419:Photoreceptor Cells, Vertebrate / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D010870:Pineal Gland / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D026423:S-Nitroso-N-Acetylpenicillamine; D015398:Signal Transduction; D014337:Trout / Q000502:physiology*
chemical_list: D009569:Nitric Oxide; D009249:NADP; D026423:S-Nitroso-N-Acetylpenicillamine; D019001:Nitric Oxide Synthase; D008058:Dihydrolipoamide Dehydrogenase; D010396:Penicillamine; D006152:Cyclic GMP; D008550:Melatonin; D015056:1-Methyl-3-isobutylxanthine