title: Synergism of atrial pressure and adrenergic stimulation for ANF release in the rat.
abstract: The effect of adrenergic stimulation on atrial natriuretic factor (ANF) release was studied in conscious rats. 60 min i.v. infusion of 15 micrograms/kg/min phenylephrine produced an elevation in mean arterial pressure of about 50 mmHg that was associated with an immediate, transitory increase in both central venous (CVP) and left ventricular end-diastolic (LVEDP) pressures. Heart rate was not changed. The elevation in CVP, but not LVEDP, persisted until 5 min, together with a 50-fold increase in plasma C-terminal ANF concentrations (from 19 +/- 5 to 1010 +/- 339 fmol/ml); at 30 min, in the absence of any increases in CVP or LVEDP, plasma ANF was still elevated by 5-fold (114 +/- 35 fmol/ml). It is suggested that adrenergic stimulation 'per se' can induce ANF release, independently of atrial pressure. Furthermore, combined adrenergic stimulation and increased atrial wall tension could result in a potentiation of the ANF secretory response 'in vivo', in the case where both stimuli are present concomitantly.
authors.affiliation: Clinical Research Institute of Montreal, Quebec, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Lachance
authors.forename: R
authors.initials: R
authors.lastname: Garcia
mesh_terms: D000818:Animals; D016275:Atrial Function; D009320:Atrial Natriuretic Factor / Q000097:blood / Q000378:metabolism*; D001794:Blood Pressure / Q000187:drug effects; D004357:Drug Synergism; D006325:Heart Atria / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D007260:Infusion Pumps; D008297:Male; D010656:Phenylephrine / Q000008:administration & dosage; D051381:Rats; D011919:Rats, Inbred Strains; D013566:Sympathomimetics / Q000008:administration & dosage*
chemical_list: D013566:Sympathomimetics; D010656:Phenylephrine; D009320:Atrial Natriuretic Factor