3-Adrenergic stimulation

Lipolysis 1 Hormone sensitive lipase (HSL) l Adrenergic stimulation of lipolysis Adipocytes... 

MISCELLANEOUS ANTIDEPRESSANTS. An uncommon but potentially serious adverse reaction of trazodone is priapism (a persistent erection of die penis). If not treated within a few hours, priapism can result in impotence The nurse instructs the patient to report any prolonged or inappropriate penile erection. Use of the drug is discontinued immediately and the primary care provider notified. Injection of a-adrenergic stimulants (eg, norepinephrine) may be helpful in treating priapism. In some cases, surgical intervention may be required. Venlafaxine may cause an increase in die blood pressure. A sustained increase in die blood pressure may indicate that die dosage of venlafaxine needs to be decreased. 

Since the discovery of renin over 100 years ago, the RAAS has been extensively studied as a prime target or site of action for many effective antihypertensives.15 Renin is produced and stored in the juxtaglomerular cells of the kidney, and its release is stimulated by impaired renal perfusion, salt depletion, and pr adrenergic stimulation. The release of renin is the rate-limiting... 

Symptomatic carotid sinus hypersensitivity also should be treated with permanent pacemaker therapy. Patients who remain symptomatic may benefit from adding an a-adrenergic stimulant such as midodrine. 

Blocker (without ISA) and ACE inhibitor therapy is recommended. /J-Blockers decrease cardiac adrenergic stimulation and reduce the risk of a subsequent MI or sudden cardiac death. ACE inhibitors improve cardiac function and reduce CV events after MI. ARBs are alternatives to ACE inhibitors in postmyocardial patients with LV dysfunction. 

Decreased HR, contractility, and blood pressure reduce MVo2 and oxygen demand in patients with effort-induced angina. j3-Blockers do not improve oxygen supply and, in certain instances, unopposed a-adrenergic stimulation may lead to coronary vasoconstriction. 

Corticosteroids increase the number of / -adrenergic receptors and improve receptor responsiveness to /f2-adrenergic stimulation, thereby reducing... 

Cardiovascular 1 Myocardial sensitivity to /J-adrenergic stimulation 1 Baroreceptor activity i Cardiac output T Total peripheral resistance... 

Mauban JRH, Lamont C, Balke CW, Wier WG 2001 Adrenergic stimulation of rat resistance arteries affects Ca2+ sparks, Ca2+ waves, and Ca2+ oscillations. Am 1 Physiol 280 H2399— H2405... 

One of the few examples of decreased susceptibility among elderly is the effect of catecholamines on the heart. There is a down-regulation of beta-adrenergic receptors and a reduced response to beta-adrenergic stimulation (Turnheim 1998). This results in decreased effect of betablockers on heart rate and stroke volume. In the elderly betablockers may be less effective than other drugs against hypertension and they should not be considered appropriate for first-line therapy of uncomplicated hypertension in the elderly (Grossman and Messerli 2002). 

The rate of absorption from an SC injection site may be retarded by immobilization of the limb, local cooling to cause vasoconstriction, or application of a tourniquet proximal to the injection site to block the superficial venous drainage and lymphatic flow. In small amounts, adrenergic stimulants, such as epinephrine, will constrict the local blood vessels and, therefore, slow systemic absorption. Conversely, cholinergic stimulants (such as methacholine) will induce very rapid systemic absorption subcutaneously. Other agents may also alter their own rate of absorption by affecting local blood supply or capillary permeability. 

Carrero I, Perez-Albarsanz MA, Carmena MJ, et al. 1990. Lindane inhibits b-adrenergic stimulation of cyclic AMP accumulation in rat prostatic epithelial cells. Pesticide Biochem Physiol 38 197-203. 

H. Pittner, H. Stormann, R. Enzenhofer, Pharmacodynamic Actions of Midodrine, a New a-Adrenergic Stimulating Agent, and Its Main Metabolite, ST 1059 , Arzneim.-Forsch. 1976, 26, 2145 - 2154. 

Although this drug is categorized as a local anesthetic, I have chosen to put it in with the hallucinogens because of the psychotomimetic effects that it produces. Cocaine is not a phenylethyl-amine, but it produces central nervous system arousal or stimulant effects which closely resemble those of the amphetamines, the methylenedioxyamphetamines in particular. This is due to the inhibition by cocaine of re-uptake of the norepinephrine released by the adrenergic nerve terminals, leading to an enhanced adrenergic stimulation of norepinephrine receptors. The increased... 

Propranolol is a prototype of this series of drugs and is the oldest and most widely used nonselective )3-adrenoblocker. It possesses antianginal, hypotensive, and antiarrhythmic action. Propranolol is a cardiac depressant that acts on the mechanic and electrophysio-logical properties of the myocardium. It can block atrioventricular conductivity and potential automatism of sinus nodes as well as adrenergic stimulation caused by catecholamines nevertheless, it lowers myocardial contractility, heart rate, blood pressure, and the myocardial requirement of oxygen. 

Pharmacology Sympathomimetic agents produce -adrenergic stimulation (vasoconstriction), - -adrenergic stimulation (increase myocardial contractility, heart rate, automaticity, and AV conduction), and 2-adrenergic activity (peripheral vasodilation). Dopamine also causes vasodilation of the renal and mesenteric, cerebral, and coronary beds by dopaminergic receptor activation. 

Elderly patients and those sensitive to -adrenergic stimulants Start with 2 mg 3 or 4 times/day. If adequate bronchodilation is not obtained, increase dosage gradually to as much as 8 mg 3 or 4 times/day. 

The pharmacologic actions of these agents include Alpha-adrenergic stimulation (vasoconstriction, nasal decongestion, pressor effects) - -adrenergic stimulation (increased myocardial contractility and conduction) and 2-adrenergic stimulation (bronchial dilation and vasodilation, enhancement of mucociliary clearance, inhibition... 

Autonomic receptors further regulate calcium influx through the sarcolemma (Fig. 15.1). (3-Adrenergic stimulation results in the association of a catalytic subunit of a G protein coupled to the (3-receptor. This stimulates the enzyme adenylyl cyclase to convert ATP to cyclic adenosine monophosphate (cAMP). Increasing cAMP production results in a cAMP-dependent phosphorylation of the L-type calcium channel and a subsequent increase in the probability of the open state of the channel. This translates to an increase in transsarcolemmal calcium influx during phase 2 (the plateau phase) of the cardiac muscle action potential. The effects of transient increases in intracellular levels of cAMP are tightly con-... 

Propranolol is indicated in the management of a variety of cardiac rhythm abnormalities that are totally or partially due to enhanced adrenergic stimulation. In selected cases of sinus tachycardia caused by anxiety, pheochromocytoma, or thyrotoxicosis, (3-blockade will reduce the spontaneous heart rate. 

Do not use OTC products containing a-adrenergic stimulants (nasal decongestants, cold remedies) unless directed by physician... 

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