title: An emerging role for gasotransmitters in the control of breathing and ionic regulation in fish.
abstract: Three gases comprising nitric oxide, carbon monoxide and hydrogen sulphide, collectively are termed gasotransmitters. The gasotransmitters control several physiological functions in fish by acting as intracellular signaling molecules. Hydrogen sulphide, first implicated in vasomotor control in fish, plays a critical role in oxygen chemoreception owing to its production and downstream effects within the oxygen chemosensory cells, the neuroepithelial cells. Indeed, there is emerging evidence that hydrogen sulphide may contribute to oxygen sensing in both fish and mammals by promoting membrane depolarization of the chemosensory cells. Unlike hydrogen sulphide which stimulates breathing in zebrafish, carbon monoxide inhibits ventilation in goldfish and zebrafish whereas nitric oxide stimulates breathing in zebrafish larvae while inhibiting breathing in adults. Gasotransmitters also modulate ionic uptake in zebrafish. Though nothing is known about the role of CO, reduced activities of branchial Na(+)/K(+)-ATPase and H(+)-ATPase activities in the presence of NO donors suggest an inhibitory role of NO in fish osmoregulation. Hydrogen sulphide inhibits Na(+) uptake in zebrafish larvae and contributes to lowering Na(+) uptake capacity in fish acclimated to Na(+)-enriched water whereas it stimulates Ca(2+) uptake in larvae exposed to Ca(2+)-poor water.
authors.affiliation: Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N6N5, Canada. sfperry@uottawa.ca.
authors.forename: Steve
authors.initials: S
authors.lastname: Perry
authors.affiliation: Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N6N5, Canada.
authors.forename: Y
authors.initials: Y
authors.lastname: Kumai
authors.affiliation: Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N6N5, Canada.|Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK.
authors.forename: C S
authors.initials: CS
authors.lastname: Porteus
authors.affiliation: Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N6N5, Canada.
authors.forename: V
authors.initials: V
authors.lastname: Tzaneva
authors.affiliation: Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N6N5, Canada.
authors.forename: R W M
authors.initials: RW
authors.lastname: Kwong
mesh_terms: D000818:Animals; D002248:Carbon Monoxide / Q000378:metabolism; D005399:Fishes; D064426:Gasotransmitters / Q000378:metabolism*; D006706:Homeostasis; D006862:Hydrogen Sulfide / Q000378:metabolism; D007473:Ion Channels / Q000378:metabolism*; D017136:Ion Transport; D008168:Lung / Q000378:metabolism*; D046569:Neuroepithelial Cells / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D012119:Respiration; D015398:Signal Transduction
chemical_list: D064426:Gasotransmitters; D007473:Ion Channels; D009569:Nitric Oxide; D002248:Carbon Monoxide; D006862:Hydrogen Sulfide
keywords: Carbon monoxide; Chemoreception; Heme oxygenase; Hydrogen sulphide; Ionocyte; Neuroepithelial cell; Nitric oxide; Osmoregulation; Ventilation; Zebrafish