Perturbations to nutrition during critical periods are associated with changes in embryonic, fetal or postnatal developmental patterns that may render the offspring more likely to develop
cardiovascular disease in later life. The aim of this study was to evaluate whether autonomic nervous system imbalance underpins in the long-term
hypertension induced by
dietary protein restriction during peri-pubertal period. Male Wistar rats were assigned to groups fed with a low
protein (4%
protein, LP) or control diet (20.5%
protein; NP) during peri-puberty, from post-natal day (PN) 30 until PN60, and then all were returned to a normal
protein diet until evaluation of cardiovascular and autonomic function at PN120. LP rats showed long-term increased mean arterial pressure (p = 0.002) and sympathetic arousal; increased power of the low frequency (LF) band of the arterial pressure spectral (p = 0.080) compared with NP animals. The depressor response to the
ganglion blocker
hexamethonium was increased in LP compared with control animals (p = 0.006). Pulse interval variability showed an increase in the LF band and LF/HF ratio (p = 0.062 and p = 0.048) in LP animals. The cardiac response to
atenolol and/or
methylatropine and the baroreflex sensitivity were similar between groups. LP animals showed ventricular
hypertrophy (p = 0.044) and increased interstitial
fibrosis (p = 0.028) compared with controls. Reduced
protein carbonyls (PC) (p = 0.030) and
catalase activity (p = 0.001) were observed in hearts from LP animals compared with control. In the brainstem, the levels of PC (p = 0.002) and the activity of
superoxide dismutase and
catalase (p = 0.044 and p = 0.012) were reduced in LP animals, while the levels of GSH and total
glutathione were higher (p = 0.039 and p = 0.038) compared with NP animals.
Protein restriction during peri-pubertal period leads to
hypertension later in life accompanied by sustained sympathetic arousal, which may be associated with a disorganization of brain and cardiac redox state and structural cardiac alteration.