INTRODUCTION Clinical studies have shown that inhaled corticosteroids can induce rapid vasoconstriction in the airways, leading to decreased mucosal blood flow. The aim of this study was to investigate whether vasoconstriction of the pulmonary circulation after short inhalation of a corticosteroid can be detected in the isolated and perfused rat lung (IPL) - a model which could serve as a subst...

Myogenic vascular response is a form of systemic and regional vasoconstriction produced increasing the intra-arterial pressure by gravity. Here, the vasoconstriction due to the myogenic response, induced by the gravitational action in a dependent limb, is separated from that caused by the baroreceptor reflex. Regional changes of skin blood flow (SBF), total blood volume of the finger (TBVF), pu...

Reversible cerebral vasoconstriction syndrome is a clinical and radiologic syndrome that represents a common presentation of a diverse group of disorders. The syndrome is characterized by thunderclap headache and reversible vasoconstriction of cerebral arteries, which can either be spontaneous or related to an exogenous trigger. The pathophysiology of reversible cerebral vasoconstriction syndro...

An overview of the possible factors that might contribute to the development of cerebral vasospasm is presented, with particular emphasis on the possibility that spasm arises from a malfunction of the regulatory or contractile processes in smooth muscle cells. This possibility is emphasized because the evidence for cellular damage and the delayed occurrence of vasospasm are suggestive of pathol...

The effects of motorcycle exhaust particulate on vasoconstriction were determined using rat thoracic aortas under organ culture conditions treated with organic extracts of motorcycle exhaust particulate from a two-stroke engine. The motorcycle exhaust particulate extract (MEPE) induced a concentration-dependent enhancement of vasoconstriction elicited by phenylephrine in the organ cultures of b...

Thromboxane A2 is not produced in normal rabbit kidneys, but its synthesis is induced in numerous renal pathological states. The presence of this potent vasoconstrictor could readily compromise renal hemodynamics. We found that the thromboxane synthetase inhibitor, OKY-1581 (sodium-3-[4,3-pyridylmethyl)phenyl]-2-methylacrylate) is effective in the perfused hydronephrotic kidney in selectively i...

Small G proteins exist in eukaryotes from yeast to human and constitute the Ras superfamily comprising more than 100 members. This superfamily is structurally classified into five families: the Ras, Rho, Rab, Arf, and Ran families that control a wide variety of cell and biological functions through highly coordinated regulation processes. Increasing evidence has accumulated to identify small G ...

Neuronal activity results in increased blood flow in the brain, a response named functional hyperemia. Astrocytes play an important role in mediating this response. Neurotransmitters released from active neurons evoke Ca(2+) increases in astrocytes, leading to the release of vasoactive metabolites of arachidonic acid from astrocyte endfeet onto blood vessels. Synthesis of prostaglandin E2 (PGE2...

Pregnancy induced hypertension (PIH) is major contributor to maternal death in developing countries. Endothelin-1 (ET-1) is the most potent vasoconstriction agent known and its serum levels are increased in PIH. Therefore it is important to elucidate maternal and neonatal factors which influence endothelin-1 serum levels. 100 pathological pregnancies and 88 controls were analyzed for blood endo...

Is there sympathetic vasoconstriction in exercising skeletal muscle? Although convincing evidence exists that demonstrates vasoconstriction in active muscle, the proposition that the sympathetic nervous system constricts skeletal muscle during exercise poses a paradox, given the robust vasodilation that occurs in muscle during exercise. Ultimately, muscle perfusion is a balance between metaboli...