Disease relevance of ADRB2

• 4. It is suggested that the muscle weakness and tremor observed in thyrotoxicosis and during administration of beta 2-adrenoceptor agonists are mediated by different mechanisms [1].
• One group of compounds including D2343 (1-(4-hydroxyphenyl)-2-[1,1-dimethyl-3-(2-methoxyphenyl) propylamino]-ethanol HCl), a new beta 2-adrenoceptor agonist, appeared to be more effective in combating bronchospasm induced by histamine than in depressing the contractions of the soleus muscle in anaesthetized cat [2].
• Superfusion with atenolol (beta 1-adrenoreceptor blocking drug) or butoxamine (beta 2-adrenoreceptor blocking drug) inhibited the pressor response and the tachycardia caused by hypothalamic stimulation [3].

High impact information on ADRB2

• Beta 2-adrenergic receptor signaling acts via NO release to mediate ACh-induced activation of ATP-sensitive K+ current in cat atrial myocytes [4].
• Effects of selective beta 1- and beta 2-adrenoreceptor agonists and antagonists on intraocular pressure in the cat [5].
• The aziridine analogues 1 represent the first of a new class of selective beta2-adrenoceptor blocking agents [6].
• 3. The beta 1- and beta 2-adrenoceptor affinity (-log equilibrium dissociation constant) of the enantiomers was determined from competition binding experiments (radioligand: [125I]-(S)-pindolol) performed in membranes prepared from the guinea-pig left ventricular free wall (predominantly beta 1) and soleus muscle (beta 2) [7].
• In the peripheral airways, histamine bronchoconstriction is mediated by H1-receptors and beta 2-adrenoceptor blockade may either potentiate or antagonize the histamine response depending on the concentration [8].

Biological context of ADRB2

• The responses of several target organs to beta 2-adrenoceptor stimulation were used: inhibition of isoprenaline effects on diastolic blood pressure, hindlimb perfusion pressure, soleus muscle contractility and histamine aerosol-induced bronchoconstriction [9].
• These results are indicative of coronary vasodilation related to beta 2-adrenergic receptor blockade and was confined to well-oxygenated areas surrounding the acutely ischaemic zone [10].
• In phentolamine-treated cats, reductions in arterial pressure and total peripheral resistance produced by infusions of dobutamine were little affected by the beta 2-adrenoceptor-selective antagonist butoxamine, but were antagonized by atenolol [11].
• For this purpose capillary pressure autoregulation in response to graded decrease in arterial pressure was studied in sympathectomized muscle in the control state, and during haemorrhagic hypovolaemia in the presence and absence of selective beta 2-adrenoceptor blockade (ICI 118,551) [12].
• We examined the beta 1- and beta 2-adrenoceptor binding properties, cellular electrophysiology, and antiarrhythmic efficacy of CK-3579 and the two enantiomers CK-4000 (S) and CK-4001 (R) [13].

Anatomical context of ADRB2

• A corresponding beta-2 adrenoceptor reserve of 30 to 50% was derived from data obtained in the soleus muscle [14].
• 4 beta2-Adrenoceptor selective agonists salbutamol and terbutaline were more potent in the lung strip than the trachea, suggesting beta2-adrenoceptors predominated in the lung strip [15].
• The developmental pattern and laminar distribution of beta 1 and beta 2 adrenergic receptor subtypes were studied in cat visual cortex with autoradiography using [125I]iodocyanopindolol as a ligand and also with immunocytochemistry using a monoclonal antibody directed against beta adrenergic receptors [16].
• The blockade of the nictitating membrane response by propranolol was however weaker than of the beta2-adrenoceptor mediated vasodepressor response [17].
• Comparison between beta 3 and beta 2 adrenoceptor agonists as inhibitors of gastric acid secretion [18].

Associations of ADRB2 with chemical compounds

• The inclusion of the oxymethylene link promotes selectivity for beta1-as opposed to beta2-adrenoceptor activity [19].
• By contrast, dopexamine is approximately 60 times more potent than dopamine as an agonist at the beta 2-adrenoceptor of the guinea-pig isolated tracheal chain, with an EC50 of 1.5 X 10(-6)M [20].
• The inhibitory effect of SR5861 IA was not modified by the non selective beta1- and beta2-adrenoceptor antagonist propranolol (1.5 micromol/kg i.v.), but it was prevented by bupranolol (10 micromol/kg i.v.), a drug endowed with beta3-antagonistic properties [21].
• We have tested the effects of phenylephrine, dobutamine and salbutamol, alpha-, beta 1- and beta 2-adrenoceptor agonists respectively, on the output of radiolabelled mucins into the cat trachea in situ [22].
• In the cerebellum the potency order was (+/-)protokylol greater than (+/-)hydroxybenzylisoproterenol greater than (+/-)isoproterenol greater than (-)epinephrine greater than (+/-)salbutamol greater than (-)norepinephrine, indicating the presence of a beta 2-adrenergic receptor [23].

Other interactions of ADRB2

• Histamine bronchoconstriction of the central airways was unmasked by non-selective and beta 2-adrenoceptor blockade but not by beta 1-adrenoceptor blockade [8].
• The systemic vasodilator response to porcine endothelin was not affected by beta 2-adrenoceptor blockade [24].

Analytical, diagnostic and therapeutic context of ADRB2

• After treatment with zaprinast (2 mg/kg, i.v.), a type V cyclic 3',5'-guanosine monophosphate-specific phosphodiesterase inhibitor, the duration of vasodilator responses to the NO* donors, as measured by T(1/2), was increased significantly, whereas the duration of the response to the beta2-adrenergic receptor agonist albuterol was unchanged [25].

References