Early changes of hypothalamic angiotensin II receptors expression in gestational protein-restricted offspring: effect on water intake, blood pressure and renal sodium handling

Abstract

The current study examines changes in the postnatal hypothalamic angiotensin receptors by maternal protein restriction (LP), and its impact on in uteri programming of hypertension in adult life. The data show that LP male pup body weight was significantly reduced when compared to that of control (NP) pups. Also, immunoblotting analysis demonstrated a significantly decreased expression of type 1 AngII receptors (AT1 R ) in the entire hypothalamic tissue extract of LP rats at 12 days of age compared to age-matched NP offspring. Conversely, the expression of the type 2 AngII (AT2 R ) receptors in 12-day-and 16-week-old LP hypothalamus was significantly increased. The current data show the influence of central AngII administration on water consumption in a concentration-dependent fashion, but also demonstrate that the water intake response to AngII was strikingly attenuated in 16-week-old LP. These results may be related to decreased brain arginine vasopressin (AVP) expression appearing in maternal protein-restricted offspring. The present investigation shows an early decrease in fractional urinary sodium excretion in maternal protein-restricted offspring. The decreased fractional sodium excretion was accompanied by a fall in proximal sodium excretion and occurred despite unchanged creatinine clearance. These effects were associated with a significant enhancement in arterial blood pressure in the LP group, but the precise mechanism of these phenomena remains unknown.

Impact of taurine supplementation on blood pressure in gestational protein-restricted offspring: Effect on the medial solitary tract nucleus cell numbers, angiotensin receptors, and renal sodium handling

“…Since these initial discoveries, most intrinsic components of the RAS, including angiotensinogen, angiotensin, and converting enzymes, have been well described and demonstrated in different areas of the central nervous system (CNS). 2,3 Notably, most previous studies in this field have focused on the central and peripheral angiotensin receptors and their roles in prenatal imprinting. The challenge for all of us is to understand in depth the mechanisms by which antenatal stress may alter normal neurophysiology of the brain RAS.…”

“…Intrauterine Impact of taurine supplementation on blood pressure in gestational proteinrestricted offspring: Effect on the medial solitary tract nucleus cell numbers, angiotensin receptors, and renal sodium handling malnutrition has been known to induce alterations in the development of several tissues, among which are the CNS. 3 The role of the CNS in the control of blood pressure and hydrosaline homeostasis has been demonstrated by several studies. 4,5 Also, the central role of the RAS in the control of blood pressure and hydroelectrolyte homeostasis has been widely demonstrated.…”

Gestational protein restriction induces CA3 dendritic atrophy in dorsal hippocampal neurons but does not alter learning and memory performance in adult offspring

“…Although the underlying mechanisms are still unclear, the association between maternal undernutrition and hormonal dysfunction has been proposed to induce intrauterine fetal programming. Studies have shown that excessive levels of fetal glucocorticoids may impair brain development, affect behavior and delay cognitive and intellectual functions later in life both in humans and animal models (Johnson et al, 1981;Uno et al, 1990Uno et al, , 1994Szuran et al, 2000;Antonow-Schlorke et al, 2001;Matthews, 2001;Antonow-Schlorke et al, 2003;French et al, 2004;Karemaker et al, 2008;Weinstock, 2008;Seckl, 2008;de Lima et al, 2012).…”

Programmed Adult Kidney Disease: Importance of Fetal Environment

“…Additionally, altered expression of AT1r in areas of the brain involved in the regulation of blood pressure has been found in protein-restricted offspring (Pladys et al, 2004;de Lima et al, 2013). This change is probably associated with the autonomic changes found in these animals.…”