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The extent of vasoconstriction may be slight or severe depending on the substance or circumstance. Many vasoconstrictors also cause pupil dilation. Medications that cause vasoconstriction include: antihistamines, decongestants, and stimulants. Severe vasoconstriction may result in symptoms of intermittent claudication. [1]
Some causes of orthostatic hypotension include neurodegenerative disorders, low blood volume (e.g. caused by dehydration, bleeding, or the use of diuretics), drugs that cause vasodilation, other types of drugs (notably, narcotics and marijuana), discontinuation of vasoconstrictors, prolonged bed rest (immobility), significant recent weight loss ...
Renin concentration in blood plasma tends to be higher in younger people with hypertension when vasoconstriction may be the main reason for high blood pressure. Conversely, renin is lower in older people or in people of African American or African Caribbean ethnicity when salt retention may contribute more to elevated blood pressure. [21]
OSA is prevalent in older adults and should be considered in cases of resistant hypertension, hypertension refractory to appropriate aggressive medical therapy. [3] OSA remains an under-diagnosed cause of secondary hypertension, likely due to the fact that many of the risk factors associated with OSA such as obesity , advanced age, and ...
Hypotension, also known as low blood pressure, is a cardiovascular condition characterized by abnormally reduced blood pressure. [1] Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood [2] and is indicated by two numbers, the systolic blood pressure (the top number) and the diastolic blood pressure (the bottom number), which are the ...
Since β 2 adrenergic receptors can cause vascular smooth muscle dilation, beta blockers may cause some vasoconstriction. However, this effect tends to be small because the activity of β 2 receptors is overshadowed by the more dominant vasoconstricting α 1 receptors.
The main cause of endothelial dysfunction is impaired bioavailability of nitric oxide. [ 1 ] In addition to acting as a semipermeable membrane , the endothelium is responsible for maintaining vascular tone and regulating oxidative stress by releasing mediators, such as nitric oxide, prostacyclin and endothelin , and by controlling local ...
A nitrovasodilator is a pharmaceutical agent that causes vasodilation (widening of blood vessels) by donation of nitric oxide (NO), [1] and is mostly used for the treatment and prevention of angina pectoris. This group of drugs includes nitrates (esters of nitric acid), which are reduced to NO in the body, as well as some other substances.