Activation of the NO/cGMP pathway modulates smooth muscle cells relaxation and hence vasoconstriction, a major hindrance for the use of cell-free haemoglobin (Hb) as blood substitute, despite conjugation with 5-kDa maleimide poly(ethylene)-glycol (PEG) reduces vasoconstriction in vivo. We aimed at assessing how a recently developed PEGylated-Hb (Deoxy-PEGHb) and manipulation of the NO/cGMP path...

Perivascular adipose tissue (PVAT) mediates buffering of vasoconstriction through activation of endothelium-derived factors. We hypothesized that the PVAT of Dahl salt-sensitive (Dahl SS) rats has reduced ability to buffer vasoconstriction. Vascular reactivity experiments were performed on aortic rings with PVAT intact (+PVAT) or removed (-PVAT), and endothelium intact (+ENDO) or removed (-ENDO...

BACKGROUND During static exercise in normal healthy humans, reflex renal cortical vasoconstriction occurs. Muscle metaboreceptors contribute importantly to this reflex renal vasoconstriction. In patients with heart failure, in whom renal vascular tone is already increased at rest, it is unknown whether there is further reflex renal vasoconstriction during exercise. METHODS AND RESULTS Thirty-...

To determine the thermoregulatory effects of propofol and nitrous oxide, we measured the threshold for peripheral vasoconstriction in seven volunteers over a total of 13 study days. We also evaluated the effect of vasoconstriction on oxyhemoglobin saturation (SpO2). Anesthesia was induced with an intravenous bolus dose of propofol (2 mg/kg), followed by an infusion of 180 micrograms.kg-1 x min-...

A new in vitro technic for the study of isolated surviving arteries and veins is described. Observations of the reactivity of 21 human and 68 swine coronary arteries to histamine, acetylcholine, l-epinephrine and l-norepinephrine are reported. Histamine and acetylcholine uniformly caused vasoconstriction of the coronary arteries of man and swine. Three potential mechanisms of coronary artery va...

The diagnostic evaluation of a patient with reversible cerebral vasoconstriction syndrome integrates clinical, laboratory, and radiologic findings. Imaging plays an important role by confirming the presence of cerebral vasoconstriction; monitoring potential complications such as ischemic stroke; and suggesting alternative diagnoses, including CNS vasculitis and aneurysmal subarachnoid hemorrhag...

In their quest for blood, most haematophagous parasites secrete vasodilators in their saliva to counter the host haemostatic response of vasoconstriction. Surprisingly, salivary gland extracts from adult female Dermacentor reticulatus and Rhipicephalus appendiculatus ticks induced constriction in a rat femoral artery model; males induced vasoconstriction or vasodilation depending on the time of...

A new in vitro technic for the study of isolated surviving arteries and veins is described. Observations of the reactivity of 21 human and 68 swine coronary arteries to histamine, acetylcholine, l-epinephrine and l-norepinephrine are reported. Histamine and acetylcholine uniformly caused vasoconstriction of the coronary arteries of man and swine. Three potential mechanisms of coronary artery va...