Effects of maternal protein restriction on central and peripheral renin-angiotensin systems in male rat offspring

• Published in: Life sciences (1973) Vol. 263; p. 118574
• Main Authors: Barros, Monique Assis de Vasconcelos, de Brito Alves, José Luiz, Barros, Rayssa Gabriella Nery, Santana e Silva, Manuel, Nasser, Souad, Tourneur, Yves, Leandro, Carol Virgínia Gois, Vidal, Hubert, Pirola, Luciano, Costa-Silva, João Henrique
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 15-12-2020; Elsevier BV; Elsevier
• Subjects: Angiotensin; Animals; Arterial Pressure - drug effects; Arterial Pressure - physiology; Blood pressure; Botulinum toxin; Casein; Chemoreception (internal); Developmental plasticity; Diet; Diet, Protein-Restricted - adverse effects; Evaluation; Female; Gene expression; Heart rate; Heart Rate - drug effects; Heart Rate - physiology; Hypertension; Hypertension - physiopathology; Intravenous administration; Kinases; Lactation; Lactation - physiology; Life Sciences; Losartan - pharmacology; Low protein diet; Male; Males; MAP kinase; Maternal Nutritional Physiological Phenomena - physiology; Nutrient deficiency; Offspring; Potassium; Potassium cyanide; Pregnancy; Prenatal Exposure Delayed Effects - physiopathology; Protein kinase; Protein undernutrition; Proteins; Rac1 protein; Radio frequency; Rats; Rats, Wistar; Renin; Renin angiotensin system; Renin-Angiotensin System - physiology; Respiration; Respiratory Rate - drug effects; Respiratory Rate - physiology; Spectral analysis; Spectrum analysis; Substrates; Toxins; Hypertension; Protein undernutrition; Renin angiotensin system; Developmental plasticity
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/j.lfs.2020.118574

We investigated the involvement of the renin angiotensin system (RAS) on the cardiorespiratory control in rats from dams fed with a low-protein diet.
Male offspring were obtained from dams fed a normoprotein diet (NP, 17% casein) and low-protein diet (LP, 8% casein) during pregnancy and lactation. Direct measurements of arterial pressure (AP), heart rate (HR) and respiratory frequency (RF) were recorded in awake 90-day-old at resting and after losartan potassium through either intracerebroventricular (ICV) microinjections or intravenous (IV) administration. Cardiovascular variability was evaluated by spectral analysis. Peripheral chemoreflex sensitivity was assessed through the potassium cyanide (KCN; 40 μg/0.1 ml/rat, IV). Gene expression was evaluated by qPCR, and MAPK (Mitogen Activated Protein Kinase) expression was evaluated by western blot.
The LP offspring had higher mean AP (MAP) and RF than NP offspring. In the spectral analysis, the LP rats also showed higher low frequency of systolic AP (NP: 2.7 ± 0.3 vs. LP: 5.0 ± 1.0 mmHg). After ICV losartan, MAP and RF in LP rats remained higher than those in NP rats, but without changes in HR. The peripheral chemoreflex was similar between the groups. LP group had lower gene expression of Rac1 (Ras-related C3 botulinum toxin substrate 1) (NP: 1.13 ± 0.06 vs. LP: 0.88 ± 0.08). Peripherally, LP rats had larger delta of MAP after IV losartan (NP: −9.8 ± 2 vs. LP: −23 ± 6 mmHg), without changes in HR and RF.
In rats, the RAS participates peripherally, but not centrally, in the maintenance of arterial hypertension in male offspring induced by maternal protein restriction.
•Protein restriction not alter cardiorespiratory dynamics after central block of AT1•Protein restriction not alter gene expression of the renin-angiotensin system central•Adults rats show larger hypotensive response after peripheral block of AT1.•Low-frequency oscillations are normalized after peripheral block of AT1.