High impact information on ADRB1

• Reconstitution of beta 1-adrenoceptor-dependent adenylate cyclase from purified components [1].
• In these reconstitution experiments we have employed the purified adenylate cyclase (C) from bovine brain and rabbit heart, the stimulatory GTP-binding protein (GS) purified from turkey erythrocytes and rabbit liver and the beta 1-adrenoceptor (R) from turkey erythrocytes [1].
• We find that the predicted structure of beta1-adrenergic receptor leads to a binding site for epinephrine that agrees well with the mutation experiments [2].
• Increase in angiotensin secretion induced by isoproterenol (10 microM) can be inhibited by beta 2-adrenoceptor antagonist ICI 118,551 (1 microM), but not by beta 1-adrenoceptor antagonist atenolol (1 microM) [3].
• Regional difference in the response mediated by beta 1-adrenoceptor subtype in bovine cerebral arteries [4].

Biological context of ADRB1

• 4. In the trachea, a beta 2-predominant tissue, betaxolol and atenolol were more selective for beta 1-adrenoceptor binding sites than beta 2-adrenoceptor binding sites, whereas ICI-118551 and butoxamine were more selective for beta 2-adrenoceptor binding sites [5].

Anatomical context of ADRB1

• The affinity of betaxolol, a beta 1-adrenoceptor-selective blocking agent, for beta-adrenoceptors in the bovine trachea and heart [5].
• A membrane preparation of the calf heart left ventricle has been used after identification and characterization, as a source of myocardial beta 1-adrenoceptor for radioligand binding studies [6].
• These results indicate the presence of a beta 1-adrenergic receptor stimulating aldosterone secretion in bovine zona glomerulosa cells [7].
• Whereas, when a beta 1-adrenoceptor preparation purified from turkey erythrocyte membranes was reconstituted, it was found nearly completely in the smaller heavier vesicle fraction II where it was incorporated inside-out [8].
• These results are consistent with a beta 1-adrenoceptor-mediated relaxation caused by (-)-noradrenaline released from sympathetic nerve endings at low stimulation frequencies [9].

Associations of ADRB1 with chemical compounds

• The bovine beta 3-adrenergic receptor has high affinity for beta 1-adrenergic receptor and beta 2-adrenergic receptor antagonists including ICI 201651 [(R)-4-(2-hydroxy-3-phenoxypropylaminoethoxy)-N-(2- methoxyethyl)phenoxy acetic acid], carazolol, and CGP 12177A [(+/-)-4-(3-t-butylamino-2- hydroxypropoxy)benzimidazol-2-one] [10].
• Blockade by metoprolol and practolol (beta 1-adrenoceptor antagonists) was poor and dobutamine (beta 1-agonist) was weakly stimulatory [11].
• The approximately equipotent effect of epinephrine and norepinephrine indicated that the beta-adrenergic effect on cAMP production is principally mediated via the beta 1-adrenergic receptor [12].
• On a non-denaturing polyacrylamide gel, the mobility of beta gamma-subunits was increased when incubated with beta 1-adrenoceptor and the beta 1-adrenergic agonist 1-(-)-isoproterenol, whereas on incubation with the antagonist 1-alprenolol the mobility was unchanged [13].
• 2. Salbutamol acted as a partial agonist on these cells hence suggesting the presence of a beta 1-adrenoceptor [14].

Other interactions of ADRB1

• 4. The adenylate cyclase of SMC was more sensitive to prostaglandins (with the ED50 for PGI2 being 0.024 mu mol/L) and glucagon than that of EC, and responded modestly to catecholamines and was almost selectively sensitive to beta1-adrenoceptor agonists [15].

References