The renal blood vessels were studied for a cholinergic determinant of their response to renal nerve stimulation. In dogs anesthetized with morphine and chloralose, control values were: mean aortic blood pressure 147 ± 4 mm Hg, renal blood flow 257 ± 12 ml/min. Acetylcholine (ACh) in 1-, 10and 100-^tg doses (all drugs given into the renal artery) increased renal blood flow, whereas 1000 fig of A...

To evaluate the effect of chronic hyperinsulinemia on blood pressure in salt-dependent hypertension, we infused insulin (1.0 IU/d, n = 15) or saline (n = 13) for 4 weeks into deoxycorticosterone acetate-salt hypertensive rats. The insulin infusion increased plasma insulin levels to 24 +/- 2 microU/mL, which was higher than in the saline-infused rats (9 +/- 1 microU/mL) but was still within the ...

We examined whether increased sympathetic nerve activity (SNA) accounts for enhanced depressor responses to ganglionic blockade in the Lewis polycystic kidney (LPK) model of chronic kidney disease (CKD) or whether it reflects increased vascular responses to vasodilation (vascular amplifier). Under urethane anesthesia, depressor responses to ganglionic blockade (hexamethonium, 0.5-40 mg/kg i.v.)...

IN his lecture " Medicine, Yesterday and To-morrow ", Sir Henry Dale mentioned, as the most recent addition to the technique of preparing a patient for a surgical operation, synthetic substances which, by their action on the sympathetic ganglia, lower the arterial blood pressure and enable a postural adjustment of the patient to produce a practically bloodless field of operation (Dale, 1951). I...

Objective(s): Cholinergic neurons are important neurons in the Pedunculopontine tegmental nucleus (PPT). In this study, nicotinic receptor of the PPT in central cardiovascular regulation in the anesthetized rat was evaluated. Materials and Methods: Saline, acetylcholine (Ach; doses: 90 and 150 nmol), hexamethonium (Hexa; doses: 100 and 300 nmol) and higher doses of Hexa (300 nmol) + Ach (150 nm...

This study aimed to determine the mechanism of hypertension associated with nitric oxide synthase inhibition. Intravenous injections of NG-nitro-L-arginine, a nitric oxide synthase inhibitor, produced a sustained increase in systemic blood pressure and a decrease in heart rate in anesthetized dogs, whereas NG-nitro-D-arginine had no effect. L-Arginine reversed the pressor response. NG-Nitro-L-a...

This study aimed to determine the mechanism of hypertension associated with nitric oxide synthase inhibition. Intravenous injections of JV-nitro-L-arginine, a nitric oxide synthase inhibitor, produced a sustained increase in systemic blood pressure and a decrease in heart rate in anesthetized dogs, whereas iV-nitro-D-arginine had no effect. L-Arginine reversed the pressor response. yV-Nitro-L-a...

The use of colored microspheres to adequately evaluate blood flow changes under different circumstances in the same rat has been validated with a maximum of three different colors due to methodological limitations. The aim of the present study was to validate the use of four different colors measuring four repeated blood flow changes in the same rat to assess the role of vasopressor systems in ...

Hindquarter peripheral resistance, calculated as arterial pressure divided by hindquarter blood flow, decreased significantly on ganglionic blockade with hexamethonium bromide in four kinds of experimentally hypertensive rats, i.e. spontaneously hypertensive rats (SHR), DOCA-salt hypertensive rats, and one-kidney, one-clip and two-kidney, one-clip renovascular hypertensive rats, but not in norm...

Acute intravenous Tempol reduces mean arterial pressure (MAP) and heart rate (HR) in spontaneously hypertensive rats. We investigated the hypothesis that the antihypertensive action depends on generation of hydrogen peroxide, activation of heme oxygenase, glutathione peroxidase or potassium conductances, nitric oxide synthase, and/or the peripheral or central sympathetic nervous systems (SNSs)....