The impact of high-fat diet consumption and inulin fiber supplementation on anxiety-related behaviors and liver oxidative status in female Wistar rats.

Background: Obesity is a worldwide public health problem associated with cognitive and mental health problems in both humans and rats. Studies assessing the effect of fiber supplementation on behavioral deficits and oxidative stress caused by high-fat diet (HFD) consumption in female rats are still scarce. We hypothesized that HFD consumption would lead to anxiety-related behavior and hepatic oxidative stress and that inulin would protect against these changes.

High-fat diet, microbiome-gut-brain axis signaling, and anxiety-like behavior in male rats.

Obesity, associated with the intake of a high-fat diet (HFD), and anxiety are common among those living in modern urban societies. Recent studies suggest a role of microbiome-gut-brain axis signaling, including a role for brain serotonergic systems in the relationship between HFD and anxiety. Evidence suggests the gut microbiome and the serotonergic brain system together may play an important role in this response.

Ivabradine restores tonic cardiovascular autonomic control and reduces tachycardia, hypertension and left ventricular inflammation in post-weaning protein malnourished rats.

Unlabelled: Malnutrition results in autonomic imbalance and heart hypertrophy. Overexpression of hyperpolarization-activated cyclic nucleotide-gated channels (HCN) in the left ventricles (LV) is linked to hypertrophied hearts and abnormal myocardium automaticity. Given that ivabradine (IVA) has emerging pleiotropic effects, in addition to the widely known bradycardic response, this study evaluated if IVA treatment could repair the autonomic control and cardiac damages in malnourished rats.

Thermoregulatory responses, heart rate, and the susceptibility to anxiety in obese animals subjected to stress.

Obesity and stress are related to cardiovascular diseases. Rats fed a high-fat diet (HFD) show increased cardiovascular reactivity to emotional stress and altered defensive behavioral responses. Indeed, changes in thermoregulatory responses in an aversive environment are observed in these animals.

Ivabradine treatment lowers blood pressure and promotes cardiac and renal protection in spontaneously hypertensive rats.

Unlabelled: Hypertension is linked to hyperpolarization-activated cyclic nucleotide-gated (HCN) function, expressed in excitable and non-excitable cells. Considering that the reduction in heart rate (HR) improves coronary perfusion and cardiac performance, ivabradine (IVA) emerged as an important drug for the treatment of cardiovascular diseases.

Aim: Evaluate if IVA chronic treatment effect can mitigate hypertension and reverse the cardiac and renal damage in SHR.

The role of peripheral transient receptor potential vanilloid 1 channels in stress-induced hyperthermia in rats subjected to an anxiogenic environment.

Anxiety resulting from psychogenic stimuli elicit stress-induced hyperthermia in rats, often called "psychogenic fever", which is part of a coordinated response to situations seen as novel or distressing. Brain transient receptor potential vanilloid 1 (TRPV1) channels modulate both thermoregulation and animal behavior; however, the role of peripheral TRPV1 channels in regulating these responses during exposure to an anxiogenic environment has not been determined. Thus, the present study aimed to investigate the involvement of abdominal TRPV1 channels in stress-induced hyperthermia and behavior in rats subjected to an unconditioned anxiety test.

Lasting effects of ketamine and isoflurane administration on anxiety- and panic-like behavioral responses in Wistar rats.

In clinical and laboratory practice, the use of anesthetics is essential in order to perform surgeries. Anesthetics, besides causing sedation and muscle relaxation, promote several physiological outcomes, such as psychotomimetic alterations, increased heart rate, and blood pressure. However, studies depicting the behavioral effect induced by ketamine and isoflurane are conflicting.

Tobacco-Free Cigarette Smoke Exposure Induces Anxiety and Panic-Related Behaviours in Male Wistar Rats.

Smokers, who generally present with lung damage, are more anxious than non-smokers and have an associated augmented risk of panic. Considering that lung damage signals specific neural pathways that are related to affective responses, the aim of the present study was to evaluate the influence of pulmonary injury on anxiety and panic-like behaviours in animals exposed to cigarette smoke with and without tobacco. Male Wistar rats were divided into the following groups: a control group (CG); a regular cigarette group (RC); and a tobacco-free cigarette (TFC) group.

Oxidative stress causes hypertension and activation of nuclear factor-κB after high-fructose and salt treatments.

There is evidence that diets rich in salt or simple sugars as fructose are associated with abnormalities in blood pressure regulation. However, the mechanisms underlying pathogenesis of salt- and fructose-induced kidney damage and/or consequent hypertension yet remain largely unexplored. Here, we tested the role of oxidative state as an essential factor along with high salt and fructose treatment in causing hypertension.

High fat diet induced-obesity facilitates anxiety-like behaviors due to GABAergic impairment within the dorsomedial hypothalamus in rats.

Overweight and obesity are conditions associated with an overall range of clinical health consequences, and they could be involved with the development of neuropsychiatric diseases, such as generalized anxiety disorder (GAD) and panic disorder (PD). A crucial brain nuclei involved on the physiological functions and behavioral responses, especially fear, anxiety and panic, is the dorsomedial hypothalamus (DMH). However, the mechanisms underlying the process whereby the DMH is involved in behavioral changes in obese rats still remains unclear.

Chronic Treatment with Ivabradine Does Not Affect Cardiovascular Autonomic Control in Rats.

A low resting heart rate (HR) would be of great benefit in cardiovascular diseases. Ivabradine-a novel selective inhibitor of hyperpolarization-activated cyclic nucleotide gated (HCN) channels- has emerged as a promising HR lowering drug. Its effects on the autonomic HR control are little known.

New insights on amygdala: Basomedial amygdala regulates the physiological response to social novelty.

The amygdala has been associated with a variety of functions linked to physiological, behavioral and endocrine responses during emotional situations. This brain region is comprised of multiple sub-nuclei. These sub-nuclei belong to the same structure, but may be involved in different functions, thereby making the study of each sub-nuclei important.

Nitric oxide modulates blood pressure through NMDA receptors in the rostral ventrolateral medulla of conscious rats.

The rostral ventrolateral medulla (RVLM) is an important site of cardiovascular control related to the tonic excitation and regulating the sympathetic vasomotor tone through local presympathetic neurons. Nitric oxide (NO) has been implicated in the modulation of neurotransmission by several areas of the central nervous system including the RVLM. However the pathways driving NO affects and the correlation between NO and glutamate-induced mechanisms are not well established.

The implication of protein malnutrition on cardiovascular control systems in rats.

The malnutrition in early life is associated with metabolic changes and cardiovascular impairment in adulthood. Deficient protein intake-mediated hypertension has been observed in clinical and experimental studies. In rats, protein malnutrition also increases the blood pressure and enhances heart rate and sympathetic activity.

Increased α1-adrenoreceptor activity is required to sustain blood pressure in female rats under food restriction.

Aims: We evaluated the effect of food restriction (FR) on the various reflexes involved in short term cardiovascular regulation; we also evaluated the contribution of the sympathetic nervous systemand of the plasmatic nitric oxide (NO) in the development of the counterregulatory cardiovascular changes triggered by FR.

Main Methods: Female rats were subjected to FR for 14 days, and after this period biochemical measurements of biochemical parameters were performed. For physiological tests, animals were anaesthetised, and a catheter was inserted into the femoral artery and vein for the acquisition of blood pressure and heart hate, and drug infusion, respectively.

The role of dorsomedial hypotalamus ionotropic glutamate receptors in the hypertensive and tachycardic responses evoked by Tityustoxin intracerebroventricular injection.

The scorpion envenoming syndrome is an important worldwide public health problem due to its high incidence and potential severity of symptoms. Some studies address the high sensitivity of the central nervous system to this toxin action. It is known that cardiorespiratory manifestations involve the activation of the autonomic nervous system.

Basal and β-adrenergic cardiomyocytes contractility dysfunction induced by dietary protein restriction is associated with downregulation of SERCA2a expression and disturbance of endoplasmic reticulum Ca2+ regulation in rats.

Background: The mechanisms responsible for the cardiac dysfunction associated with dietary protein restriction (PR) are poorly understood. Thus, this study was designed to evaluate the effects of PR on calcium kinetics, basal and β-adrenergic contractility in murine ventricular cardiomyocytes.

Methods: After breastfeeding male Fisher rats were distributed into a control group (CG, n = 20) and a protein-restricted group (PRG, n = 20), receiving isocaloric diets for 35 days containing 15% and 6% protein, respectively.

Protein restriction after weaning modifies the calcium kinetics and induces cardiomyocyte contractile dysfunction in rats.

Protein restriction (PR) is associated with cardiovascular diseases. The purpose of this study was to investigate the effects on single ventricular cardiomyocyte contractile function of a short-term PR after weaning. Male Fischer rats that were 28 days old were randomly divided into a control group (CG, n = 16) and a protein-restricted group (PRG, n = 16).

Malnutrition alters the cardiovascular responses induced by central injection of tityustoxin in Fischer rats.

Scorpion envenoming and malnutrition are considered two important public health problems in Brazil, involving mainly children. Both these conditions are more common among the economically stratified lower income portion of the population, thus suggesting that these factors should be analyzed concomitantly. It is known that cardiorespiratory manifestations, as cardiac arrhythmias, arterial hypertension and hypotension, pulmonary edema and circulatory failure are the main "causa mortis" of scorpion envenomation.

Protein malnutrition modifies medullary neuronal recruitment in response to intermittent stimulation of the baroreflex.

Protein malnutrition after weaning changes the neurotransmission in neural pathways that organize cardiovascular reflexes in rats. The present study evaluates whether protein malnutrition alters the expression of c-fos protein (immediate-early gene expression) in central areas involved in the control of cardiovascular reflexes after intermittent stimulation of the baroreflex. The main nuclei we focused were paraventricular hypothalamus (PVH); nucleus tract solitarii (NTS); rostral ventromedial medulla (RVMM); rostral (RVLM) and caudal ventrolateral medulla (CVLM).

Increased activity of the renin-angiotensin and sympathetic nervous systems is required for regulation of the blood pressure in rats fed a low-protein diet.

Previous studies have shown that postweaning protein restriction induces changes in the sympathetic nervous system in rats, leading to alterations in cardiovascular parameters. In addition, the renin-angiotensin system is also affected in these animals. Here, we hypothesized that adjustments in the interaction between the RAS and SNS underlie the cardiovascular adaptations observed in rats fed a low-protein diet.

Cardiac responses of rats submitted to postnatal protein restriction.

Undernutrition during critical stages of development and childhood has important effects on cardiovascular homeostasis. The present study was undertaken to evaluate the in vivo and ex vivo cardiac function of rats submitted to postnatal protein restriction. Male Wistar rats (28 days old) were fed a regular (20%) or low-protein (6%) diet over 5 weeks.

Gestational and postnatal protein deficiency affects postnatal development and histomorphometry of liver, kidneys, and ovaries of female rats' offspring.

Pre- and postnatal protein deficiency may lead to decreased foetal intra-uterine development and postnatal growth, which is common in developing countries. The present study aimed to investigate the consequences of a low-protein intake during gestation and postnatally on adult female rats' offspring. Female rats were given either a control or a protein-deficient diet throughout the gestation and lactation periods.

Malnutrition during central nervous system growth and development impairs permanently the subcortical auditory pathway.

The brain that grows and develops under the continued influence of malnutrition presents permanent impairment on functioning and neurotransmitter release. The aim of this study was to investigate the chronic effects of neonatal food restriction on neurochemical and neurodynamical aspects within the primary auditory sensory pathway. Our working hypothesis is that neonatal malnutrition may affect the flow of primary sensory information both at a neurochemical and neurodynamical level.