Interference with the renin-angiotensin system reduces the palatability of 0.3 M NaCl in sodium-deplete rats

Author(s)

Zenatti, A. A. ^[1] ; Pereira Jr, E. D. ; Possari, J. ^[2] ; Andrade, C. A. F. ^[2] ; Menani, V, J. ; De Luca Jr, L. A.

Affiliation

^[1] Sao Paulo State Univ, Sch Dent FOAr, Dept Physiol & Pathol, UNESP, Araraquara, SP - Brazil

^[2] Pereira Jr, Jr., E. D., Sao Paulo State Univ, Sch Dent FOAr, Dept Physiol & Pathol, UNESP, Araraquara, SP - Brazil

• Document type: Journal article
• Source: APPETITE; v. 158, MAR 1 2021.
• Web of Science Citations: 0

Abstract

The renin-angiotensin system (RAS) controls hypertonic NaCl intake driven by sodium appetite. Here we investigated whether the antagonism of RAS interferes with hedonic and aversive omfacial motor responses, or palatability, to intraoral infusion of 0.3 M NaCl (hNaCl). Adult rats were depleted of sodium by combined sc injection of furosemide and 24 h removal of ambient sodium. In experiment 1, losartan (AT1 angiotensin II receptor antagonist, intracerebroventricular, 200 mu g/mu l), produced a three-fold increase in aversive orofacial motor responses to hNaCl. Losartan also suppressed hNaCl intake recorded immediately thereafter. In experiment 2, each animal had repeated recordings of hNaCl intake and omfacial responses to hNaCl distributed for 180 min. Paired recordings of intake and orofacial responses occurred within five successive blocks after the recordings of only orofacial responses when the animals were still sodium deplete (block zero). Captopril (angiotensin converting enzyme blocker, intraperitoneal, 30 mg/kg) inhibited by 75% the hedonic orofacial responses to hNaCl in blocks zero and 1. The hedonic responses to captopril remained the same throughout blocks, but became similar to vehicle from blocks 2 to 5. There was no difference in aversive responses to 0.3 M NaCl between captopril and vehicle. Captopril produced a 70-100% inhibition of hNaCl intake in blocks 1 to 5. The results suggest that angiotensin II acts in the brain increasing the palatability of hypertonic sodium during the consummatory phase of sodium appetite. (AU)

• FAPESP's process: 15/23467-7 - Experimental pathophysiology: role of central mechanisms of the cardiovascular and respiratory control changes induced by experimental hypertension and obesity
• Grantee: Eduardo Colombari
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 11/50770-1 - Neural mechanisms involved of hydroelectrolytic balance and cardiorespiratory control
• Grantee: José Vanderlei Menani
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/01220-0 - Role of alpha2-adrenoceptor activation on orofacial reactivity to salty taste and capsaicin in sodium-deplete rats
• Grantee: Juliana Possari
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 15/20500-3 - Role of lateral parabrachial nucleus and forebrain angiotensinergic receptors in the control of hydro mineral balance during primary hypertension.
• Grantee: Carina Aparecida Fabrício de Andrade
• Support Opportunities: Regular Research Grants