Epinephrine with 3 adrenergic receptor

Serious adverse effects of epinephrine potentially occur when it is given in an excessive dose, or too rapidly, for example, as an intravenous bolus or a rapid intravenous infusion. These include ventricular dysrhythmias, angina, myocardial infarction, pulmonary edema, sudden sharp increase in blood pressure, and cerebral hemorrhage. The risk of epinephrine adverse effects is also potentially increased in patients with hypertension or ischemic heart disease, and in those using (3-blockers (due to unopposed epinephrine action on vascular Ui-adrenergic receptors), monoamine oxidase inhibitors, tricyclic antidepressants, or cocaine. Even in these patients, there is no absolute contraindication for the use of epinephrine in the treatment of anaphylaxis [1,5,6]. 

Sympathetic nerves. The afferent and efferent arterioles are densely innervated with sympathetic nerves. Norepinephrine released directly from the nerves or circulating epinephrine released from the adrenal medulla stimulates a, adrenergic receptors to cause vasoconstriction. The predominant site of regulation is the afferent arteriole. Under normal resting conditions, there is little sympathetic tone to these vessels so that RBF is comparatively high. As discussed previously, this facilitates glomerular filtration. 

As drugs of mixed action, amphetamines activate adrenergic receptors and simultaneously release endogenic catecholamines (norepinephrine and dopamine) from neurons of the brain and periphery. Sympathomimetic effects on the periphery are very similar to those of ephedrine. Amphetamine elevates systolic and diastolic blood pressure and has weakly expressed, broncholytic action. These effects are more prolonged, yet less expressed, than with epinephrine. The distinctive feature of amphetamines is their psychostimulatory activity. Larger doses can cause hallucinations and mental conditions similar to paranoid schizophrenia. As a sympathomimetic, amphetamine is sometimes used for uterine inertia. Synonyms of amphetamine are phenamine and benzedrine. 

Similar to findings in animal models of early-life stress, elevated 24-hour urinary NE, epinephrine (E), and dopamine (DA) excretion as well as decreased platelet adrenergic receptors have been measured in abused children with PTSD (Perry, 1994 DeBellis et al., 1999a). Abused children with PTSD also exhibit... 

The /3-adrenergic receptor is an integral protein with seven hydrophobic regions of 20 to 28 amino acid residues that snake back and forth across the plasma membrane seven times. This protein is a member of a very large family of receptors, all with seven transmembrane helices, that are commonly called serpentine receptors, G protein-coupled receptors (GPCR), or 7 transmembrane segment (7tm) receptors. The binding of epinephrine to a site on the... 

As noted earlier, signal-transducing systems undergo desensitization when the signal persists. Desensitization of the /3-adrenergic receptor is mediated by a protein kinase that phosphorylates the receptor on the intracellular domain that normally interacts with Gs (Fig. 12-17). When the receptor is occupied by epinephrine,... 

ADP (Adenosine diphosphate) 536 in adenylate system 302 - 304 complexes with metal ions 296 dissociation as acid 288 intracellular concentration 304 P-31 NMR spectrum 642 pka value of 293 in regulation 535 ADP-ribose (ADPR) 315, 778, 780 ADP-ribosylation 545, 778 ADP-ribosylation factors (ARFs) 559 Adrenaline (epinephrine) 534, 542, 553, 553s in adrenergic receptor 535 a-Adrenergic receptors 553, 558, 563 p-Adrenergic receptors 553, 554 in asthma 553 in heart failure 553 receptor kinase 553 structure (proposed) 534, 555 topology 555... 

Epinephrine (Adrenalin, Bronkaid Mist, Primatene Mist, others). Epinephrine appears to directly stimulate all adrenergic receptor subtypes and is administered for a variety of reasons. Epinephrine is found in many antiasthmatic inhalation products because of its ability to stimulate beta-2 receptors on the bronchi. Because it stimulates vascular alpha-1 receptors, epinephrine may be applied topically to produce local vasoconstriction and control bleeding during minor surgical procedures (e.g., suturing superficial wounds). Likewise, epinephrine may be mixed with a local anes-... 

Epinephrine activates platelets through the a-adrenergic receptor coupled to a G-protein receptor, It is proposed that this agonist shares with ADP the P2Y 2 receptor signaling (16). 

There are two kinds of catecholamine receptors, the a and fi receptors. The former respond best to norepinephrine, whereas the latter prefer epinephrine. Norepinephrine is normally associated with neurotransmission, and a-adrenergic receptors are indeed found in tissues serviced by the sympathetic nervous system. An example is the smooth muscle, which contracts in response to stimulation by... 

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