Answer:
Inhibits adrenergic receptors, blocks the actions of endogenous adrenergic neurotransmitters epinephrine and norepinephrine. At the moment there are no known clinical useful anti-dopaminergic actions in the peripheral nervous system, but the blockade of dopaminercial receptors in the central nervous system are of great clinical importance.
Selective alpha 1 adrenergic receptor blockers lower blood pressure by post-synaptic blockage, reversing the vasoconstrictive effect of norepinephrine.
They produce arterial and venous dilation, minute volume limitations, a tendency to decrease blood pressure in standing compared to supine, hydrosaline retention and relaxation of the bladder trigone, improving the
obstructive symptoms of the lower urinary tract
Explanation:
Its use has decreased since the publication of the ALLHAT study (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial), where alpha blocker was less effective as an antihypertensive and increased incidence of cerebral events and congestive HF. The JNC 7 and other guidelines do not routinely recommend the use of alpha blockers in the treatment of arterial hypertension.
