title: Proton pump-rich cell secretes acid in skin of zebrafish larvae.
abstract: The mammalian kidney excretes its metabolic acid load through the proton-transporting cells, intercalated cells, in the distal nephron and collecting duct. Fish excrete acid through external organs, gill, or skin; however, the cellular function is still controversial. In this study, molecular and electrophysiological approaches were used to identify a novel cell type secreting acid in skin of zebrafish (Danio rerio) larvae. Among keratinocytes covering the larval surface, novel proton-secreting ionocytes, proton pump (H(+)-ATPase)-rich cells, were identified to generate strong outward H(+) flux. The present work demonstrates for the first time, with a noninvasive technique, H(+)-secreting cells in an intact animal model, the zebrafish, showing it to be a suitable model in which to study the functions of vertebrate transporting epithelia in vivo.
authors.affiliation: Institute of Cellular and Organismic Biology, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China.
authors.forename: Li-Yih
authors.initials: LY
authors.lastname: Lin
authors.forename: Jiun-Lin
authors.initials: JL
authors.lastname: Horng
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Kunkel
authors.forename: Pung-Pung
authors.initials: PP
authors.lastname: Hwang
mesh_terms: D000143:Acids; D000818:Animals; D003208:Concanavalin A / Q000378:metabolism; D004594:Electrophysiology / Q000379:methods; D004791:Enzyme Inhibitors / Q000378:metabolism; D017403:In Situ Hybridization; D007814:Larva / Q000033:anatomy & histology / Q000378:metabolism; D018942:Macrolides / Q000378:metabolism; D017494:Proton Pumps / Q000378:metabolism*; D006180:Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism; D012867:Skin / Q000166:cytology* / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000235:genetics / Q000378:metabolism; D015027:Zebrafish / Q000033:anatomy & histology* / Q000502:physiology; D029961:Zebrafish Proteins / Q000378:metabolism
chemical_list: D000143:Acids; D004791:Enzyme Inhibitors; D018942:Macrolides; D017494:Proton Pumps; D029961:Zebrafish Proteins; D003208:Concanavalin A; C040929:bafilomycin A1; D006180:Proton-Translocating ATPases; D000254:Sodium-Potassium-Exchanging ATPase