Laser Doppler flowmetry (LDF) signal responses have been compared with metabolic changes using both a surface macroprobe and randomly placed implantable microprobes in muscles of the constant-flow-perfused rat hindlimb. Changes in response to total flow and to vasoconstrictors that are known to increase (norepinephrine, NE) or decrease (serotonin, 5-HT) hindlimb oxygen uptake were assessed. The...

In the present experiments the effect of long-term peripheral ischemia on the capillary of two hind limb skeletal muscles was investigated in spontaneously hypertensive rats. Furthermore, the effect of antihypertensive therapy on changes in capillarity and on the previously observed hyperreactivity of the ischemic vascular bed to vasoconstrictors was investigated in perfused hind limbs of rats ...

To clarify the effects of active vitamin D3 on pressor and vascular responses to vasoconstrictor substances, we studied pressor responses to the intravenous injection of norepinephrine or angiotensin II (Ang II) and vasoconstrictor responses to norepinephrine. Sprague-Dawley rats were given 1,25-dihydroxyvitamin D3 subcutaneously (200 ng/kg per day) for 14 days. The administration of 1,25-dihyd...

Small-artery responses to vasoconstrictor agonists are important for vascular function. To investigate the signaling pathways involved in contraction, we studied the activation and regulation of p38 mitogen-activated protein kinases (p38MAPKs) and heat shock protein (HSP) kinase by endothelin and noradrenaline in rat mesenteric arteries. Both vasoconstrictors activated p38alpha and/or p38beta b...

OBJECTIVES We sought to determine the role of oxidative stress in the development of vascular dysfunction in inflammation. BACKGROUND Hyporeactivity to catecholamines and other vasoconstrictors is present in acute inflammation. Because oxidative stress plays a significant role in inflammation, impaired responsiveness may be overcome by anti-oxidants. METHODS In randomized, double-blind, cro...

Mitogens and vasoconstrictors stimulate many of the same early intracellular signals (e.g. phospholipase C and protein kinase C activation) in vascular smooth muscle cells (VSMC). Despite these shared signals, angiotensin II is not mitogenic for cultured VSMC. The nonmitogenic effect of angiotensin II suggests that other intracellular signals associated with growth should differ between mitogen...

Hepatorenal syndrome (HRS) is a functional renal failure that often occurs in patients with cirrhosis and ascites. HRS develops as a consequence of a severe reduction of effective circulating volume due to both an extreme splanchnic arterial vasodilatation and a reduction of cardiac output. There are 2 different types of HRS. Type 1 HRS, which is often precipitated by a bacterial infection, esp...

complex mechanisms have been known for keeping blood pressure in normal level. in fact, these mechanisms have inter-related functions and can be dysregulated by both internal and external stimuli while cardiovascular system functions to minimize these changes. vasoconstrictors can cause clinical and hemodynamical changes as 1-2 cartridges of epinephrine containing lidocaine can has no considera...