Impairment of natriuresis and diuresis induced by intrarenal adrenoceptor mechanisms in an experimental model of cirrhosis in rats.

The contribution of intrarenal alpha-2 adrenergic receptors in mediating the enhanced renal excretory responses evoked by the alpha-2-agonist xylazine was examined in a model of cirrhosis in rats. In sham-operated rats, xylazine (0.2 mg/kg, .

Raphe obscurus neurons participate in thermoregulation in rats.

In mammalian, several evidences suggest that central serotonin participates in thermoregulation. Nucleus raphe obscurus (NRO), a serotonergic nucleus, has been recognized to be the source of generation of various hemodynamic patterns in different behavioral conditions, but its involvement in thermoregulation is unclear. In the present study, extracellular action potentials of NRO neurons were recorded in anesthetized rats, which were submitted to cold and warm stimuli in the tail.

High-frequency transcutaneous electrical nerve stimulation reduces pain and cardio-respiratory parameters in an animal model of acute pain: participation of peripheral serotonin.

The objective of this study was to investigate the effect of high-frequency transcutaneous electrical nerve stimulation (HF-TENS) in antihyperalgesia, assessed through changes of sciatic nerve activity and its effects on cardiorespiratory parameters, using formalin-induced nociception in anesthetized rats. The animals were divided into formalin (FORM) and HF-TENS groups. All rats received injections of 5% formalin (50 μl, right hind-paw).

Influence of gender and estrous cycle on plasma and renal catecholamine levels in rats.

Several studies have demonstrated that gonadal hormones show significant effects on the brain and signaling pathways of effector organs/cells that respond to neurotransmitters. Since little information is available concerning the impact of male and female gonadal hormones on the renal and peripheral sympathetic system, the objective of this study was to further assess whether and how the renal content and plasma concentration of catecholamines are influenced by gender and the estrous cycle in rats. To achieve this, males Wistar rats were divided into 4 groups: (i) sham (i.

Raloxifene reduces blood pressure in hypertensive animals after ovarian hormone deprivation.

Raloxifene is a selective oestrogen receptor modulator that has been approved for the prevention and treatment of osteoporosis in post-menopausal women. Studies have revealed several effects of raloxifene on the cardiovascular system, which might contribute to the blood pressure regulatory mechanisms, particularly in the systemic arterial hypertension. Therefore, the aim of this study was to investigate the effects of raloxifene on the blood pressure, renal excretion of water and Na(+) and plasma nitrite/nitrate levels in 2-kidney-1-clip (2K1C) hypertensive female rats.

Cardiovascular risk factors, their associations and presence of metabolic syndrome in adolescents.

Objective: To evaluate the occurrence of metabolic syndrome (MS) and independent associated risk factors in adolescents in the city of Vitória, Brazil.

Methods: We assessed 380 adolescents aged 10 to 14 years attending public schools. Body mass index and blood pressure at rest were measured.

Chronic treatment with mianserin prevents DOCA-salt hypertension in rats--evidence for the involvement of central 5-HT2 receptors.

Central 5-HT2A receptors have been implicated in central volume control by activating a central angiotensinergic pathway to cause the release of vasopressin. Interestingly, to induce DOCA-salt hypertension in rats vasopressin release is required. Thus the present experiments were carried out to determine whether continuous blockade of these receptors over 20 days, with the non-selective 5-HT2 receptor antagonist mianserin would prevent the development of deoxycorticosterone acetate (DOCA)-salt hypertension.

Activity of angiotensin-converting enzyme after treatment with L-arginine in renovascular hypertension.

The renin-angiotensin system plays a role in the pathophysiology of renovascular hypertension. In addition, some studies have demonstrated a beneficial effect of L-arginine (L-Arg), the precursor of nitric oxide (NO), in this model of hypertension. This study was designed to investigate the effects of L-Arg on cardiovascular parameters and on the activity of the angiotensin-converting enzyme (ACE), after 14 days of renovascular hypertension.