title: Biological actions of atrial natriuretic factor in flatfish.
abstract: Flounder adapted to seawater were chronically cannulated and received a single i.v. injection of either saline (control) or 10 µg/kg b.w. of human ANF. Compared to controls, ANF significantly reduced (p<0.001) mean arterial blood pressure; full recovery was evident after 4 hours. Blood samples taken at intervals after saline or ANF injection showed that ANF caused a marked increase of 33.7 µg/100 ml in plasma cortisol concentration (p<0.001) 5 hours post injection. The rate of recovery of(22)Na in seawater after a single i.v. injection of 14×10(6) cpm/kg(22)NaCl was significantly increased (p<0.01) following ANF injection compared to controls suggesting that ANF stimulates Na(+) efflux. This observation was confirmed in plaice and dab. The steroidogenic action of ANF and its ability to promote Na(+) efflux are discussed in relation to its potential osmoregulatory role in teleost fish.
authors.affiliation: Department of Physiological Sciences, School of Biological Sciences, University of Manchester, M13 9PT, Manchester, England.
authors.forename: D
authors.initials: D
authors.lastname: Arnold-Reed
authors.forename: N
authors.initials: N
authors.lastname: Hazon
authors.forename: R J
authors.initials: RJ
authors.lastname: Balment