Alpha-adrenergic antagonists

Alfuzosin (Uroxatral) [Selective Alpha Adrenergic Antagonist]... 

Tolazoline (Priscoline) [Alpha Adrenergic Antagonist] Uses PCTiphCTal vasospastic disord s Action Competitively blocks a-adren gic... 

FIGURE 6—32. Side effects of the tricyclic antidepressants—part 3. In this diagram, the icon of the TCA is shown with its alpha adrenergic antagonist (alpha) portion inserted into alpha adrenergic receptors, causing the side effects of dizziness, decreased blood pressure, and drowsiness. 

FIGURE 6-27. Shown here is an icon of a tricyclic antidepressant (TCA). These drugs are actually five drugs in one (1) a serotonin reuptake inhibitor (SRI) (2) a norepinephrine reuptake inhibitor (NRI) (3) an anticholinergic/antimuscarinic drug (Ml) (4) an alpha adrenergic antagonist (alpha) and (5) an antihistamine (HI). 

Alpha-adrenergic antagonists are used primarily as antihypertensive drugs because of their ability to block vascular alpha-1 receptors. Beta-adrenergic antagonists (beta blockers) are administered primarily for their inhibitory effects on myocardial function and are used in the prevention and treatment of hypertension, angina pectoris, arrhythmias, and myocardial reinfarction. Many of the drugs introduced in this chapter are discussed further in chapters that deal with the specific clinical conditions (e.g., hypertension, asthma, and other disorders). 

The bovine parathyroid gland also possesses an alpha-adrenergic receptor (16). However, it seems improbable that an interaction between dopamine and the alpha-adrenergic receptor accounts for the physiological and biochemical effects of dopamine upon this tissue. Phentolamine, an alpha-adrenergic antagonist, has no effect on... 

An example of this approach applied to drug discovery is provided by the alpha-adrenergic antagonist drug, phenoxybenzamine, shown as 35 in Scheme 19.11. The construction of 35 actually borrowed from the nitrogen mustards. However, 35 was designed... 

Alpha blockers Alpha adrenergic antagonists compete with endogenous catecholamines for binding at and CC receptors. Because norepinephrine and epinephrine cannot bind to a receptor that is occupied by an antagonist, the actions of catecholamines at... 

V. Drug or laboratory interactions. Additive or synergistic effects may occur with other antihypertensive agents, especially other alpha-adrenergic antagonists (eg, prazosin, terazosin, or yohimbine). 

Antagonism of several characteristic effects of amphetamine and cocaine by the alpha adrenergic receptor antagonist prazosin is a most recent example of noradrenergic mechanisms in the actions of psychomotor stimulants (Tessel and Barrett 1986). We investigated whether or not prazosin may attenuate the disruptive effects of amphetamine on social and aggressive behavior in mice and squirrel monkeys (Miczek, unpublished observations). Pretreatment with prazosin (0.4 mg/kg) attenuated the disruption of attack... 

Zhang, X.Y., Kosten, T.A. Prazosin, an alpha-1 adrenergic antagonist, reduces cocaine-induced reinstatement of drug-seeking. Biol. Psychiatry. 57 1202, 2005. 

Prazosin volume, thereby reduces cardiac output Alpha-adrenergic receptor antagonist, inhibits symphathetic... 

Bradley, E.K., Beroza, P., Penzotti, J.E., Grootenhuis, P.D.J., and Spellmeyer, D.C. Miller, a rapid computational method for lead evolution description and application to alpha(l)-adrenergic antagonists./. Med. Chem. 2000, 43, 2770-2774. 

Li B-M, Mei ZT (1994) Delayed response deficit induced by local injection of the alpha-2 adrenergic antagonist yohimbine into the dorsolateral prefrontal cortex in young adult monkeys. Behav Neural Biol 62 134-139... 

Lowe FC. Roie of the newer alpha,-adrenergic-receptor antagonists in the treatment of benign prostatic hyperplasia-related lower urinary tract symptoms. Clin Ther... 

Mecfianism of Action An ergotamine derivative, alpha-adrenergic blocker that directly stimulates vascular smooth muscle. May also have antagonist effects on sero-fonin. Therapeutic Effect Peripheral and cerebral vasoconstriction. Pharmacokinetics Slow, incomplete absorption from the gastrointestinal (GI) tract rate of absorption of intranasal route varies. Protein binding greaterthan 90%. Undergoes extensive first-pass metabolism in liver. Metabolized to active metabolite. Eliminated in feces via biliary system. Half-life 7-9 hr. 

It is a adrenergic antagonist which can block both alpha and beta receptors. It is... 

Taylor F, Raskind MA (2002) The alpha 1-adrenergic antagonist prazosin improves sleep and nightmares in civilian trauma posttraumatic stress disorder. J Clin Psychopharmacol 22 82-85... 

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