The effects of strenuous exercise before and during pregnancy on the renal function and morphological alterations of the progeny were determined in a study on female Wistar rats. This research was done based on a previous study carried out in our laboratory, which showed morphological alterations in rats submitted to this kind of exercise. As the form is related to the function, the physiological relevance of submitting a pregnant female to a high-intensity exercise training regimen could be explained by the fact that morphological alterations can influence kidney function. The animals were assigned to one of two groups: control animals that did not exercise during pregnancy and trained animals that swam for 120 min 5 days a week for 8 weeks before pregnancy and daily for 60 min over a period of 8 weeks starting on the second day of pregnancy. Seven rats of each group were analyzed for morphological alterations and for renal function. The progeny of the rats used for morphological evaluation were born by cesarean section and the progeny of the animals used to evaluate renal function were born normally. The progeny were two months old when renal function was evaluated. Fertility and morbidity were the same for both groups. Strenuous maternal exercise had no significant influence on glomerular filtration rate (GFR) but renal plasma flow was lower in the progeny of the trained group (mean ± SD, 16.65 ± 3.77 ml min -1 kg -1 ) compared to the progeny of the control group (33.42 ± 2.56 ml min -1 kg -1 ). Antidiuretic and antinatriuretic effects on the progeny of the trained group were observed, since urine flow as percentage of GFR and the fraction of urinary sodium excretion were lower in this group (1.38 ± 0.10 and 0.60 ± 0.04%, respectively) compared to the progeny of the control group (2.36 ± 0.11 and 1.55 ± 0.20%, respectively). Moreover, in this exercise program, fetuses from trained animals were small-sized (2.45 ± 0.19 vs 4.66 ± 2.45 g for control animals) and showed lower differentiation compared to fetuses from the control group. These effects were probably caused by caloric restriction, hypoxia and reduction of umbilical cord length.
Elevated blood pressure (BP) is a growing burden worldwide, leading to over 10 million deaths each year. In Mozambique, two national surveys of risk factors for chronic diseases were done, using the WHO STEPWISE approach, the first in 2005 and the last in 2014/2015. In this period of 10 years, the prevalence of hypertension in the adult population increased from 33.1% to 38.9% and the extremely low levels of awareness, treatment, and control did not change significantly. May Measurement Month (MMM) is a global initiative of the International Society of Hypertension aimed at raising awareness of high BP and to act as a temporary solution to the lack of screening programmes worldwide. An opportunistic cross-sectional survey of volunteers aged ≥18 years was carried out in May 2017. Blood pressure measurement, the definition of hypertension and statistical analysis followed the standard MMM protocol. Screening was conducted by volunteers, mainly in work places, markets, and religious activities, in the capital city, in most of the provincial capitals and some rural districts. About 4454 individuals were screened with a mean age of 39 years, and, after multiple imputation, 1371 (31.1%) had hypertension. Of individuals not receiving anti-hypertensive medication, 1099 (26.6%) were hypertensive. Of individuals receiving antihypertensive medication, 166 (61.6%) had uncontrolled BP. MMM17 was the largest BP screening campaign undertaken in Mozambique. These results suggest that opportunistic screening is an important tool to identify significant numbers of patients with raised BP.
High salt intake is a determinant factor for hypertension in humans and animals’ models. Many studies indicate that the paraventricular hypothalamus (PVH) contributes to the regulation of body fluids homeostasis and neural control of circulation in salt‐induced hypertension, with the involvement of the baroreflex function, as part of a hypothalamic‐brainstem circuitry. Here, our aim was to evaluate the autonomic balance and the neuronal activity of PVH in response to baroreflex activation of animals subjected to high salt intake. Ethical protocols were approved by the Institutional Animal Care and Use Committee (n.127/2017) of the ICB/USP. Male Wistar rats (300‐400 g) received a solution of NaCl 2% in replacement of the tap water (SALT) for 7 days, while the control (CT) received only tap water. On the sixth day, rats had femoral artery catheterized for monitoring of the MAP and HR, and the femoral vein to infusion of drugs. The next day, baroreflex function was evaluated by bolus injections of phenylephrine (PHE; 0.1‐12,8 µg/Kg) and sodium nitroprusside (NPS: 0.2‐25.6 µg/Kg)]. Sigmoidal logistic equation was used to analysis baroreflex function. The cardiac autonomic balance was evaluated with injection of muscarinic receptor antagonist (ATROP; methylatropine bromide; 2 mg/Kg) and 15 min later with beta‐1‐adrenergic receptor antagonist atenolol (ATN; 4 mg/Kg). The neuronal activity in the PVH was evaluated by the FOS expression during baroreflex function challenge [a ramp infusion PHE (18‐22 µg/Kg/min)]. After 90 min the animals were euthanized, and brain tissue fixed for immunoperoxidase procedures, and subsequent cells counting analysis. Data were expressed as mean±SEM, analyzed by Student's t‐test or ANOVA two‐way (*P<0.05). Salt‐loading elicited an increase in the MAP (SALT: 115±3 vs. CT: 109±3* mmHg, t‐test, n=11) and HR (SALT: 406±10 vs. CT: 318±9* b/min, t‐test, n=11) followed by an attenuation on the range of the baroreflex function (SALT: 169±14 vs. CT: 233±22* b/min, t‐test, n=6). As for the autonomic balance salt‐loaded rats have shown an increase in the sympathetic tonus (SALT: 104±11 vs. CT: 59±7* Δb/min, t‐test, n=6), but no change in the parasympathetic tonus (SALT: ‐68±13 vs. CT: ‐48±11 Δb/min, t‐test, n=6). The activation of the arterial baroreflex resulted in an increase in the number FOS neurons in the PVH in SALT group (SALT‐PHE: 1,012±96*) compared to CT‐PHE: 345±57, (ANOVA: *P<0,05, n=4), but no change among CT‐PHE vs. CT‐NOT‐PHE neither SALT‐NOT‐PHE. The large number of FOS‐positive neurons occurred in medial level of the PVH in the SALT group, specifically in the neuron clusters of the lateral magnocellular (90%), dorsal cap (83%), medial parvicellular (71%) and ventral part (66%) when compared to the other groups. Taken together, these results show that 7 days of high salt intake elicits hypertension, impairment of baroreflex function and increase in the sympathetic tone to the heart with activation of distinct neuronal populations in the PVN. The precise neuronal mechanisms involved in ...
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