دورية أكاديمية
Beta 2-adrenoceptor agonist-induced down-regulation after short-term exposure.
| العنوان: | Beta 2-adrenoceptor agonist-induced down-regulation after short-term exposure. |
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| المؤلفون: | Hardin AO; Department of Pediatrics, Le Bonheur Children's Medical Center, Memphis, TN 38103, USA., Lima JJ |
| المصدر: | Journal of receptor and signal transduction research [J Recept Signal Transduct Res] 1999 Sep; Vol. 19 (5), pp. 835-52. |
| نوع المنشور: | Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S. |
| اللغة: | English |
| بيانات الدورية: | Publisher: Informa Healthcare Country of Publication: England NLM ID: 9509432 Publication Model: Print Cited Medium: Print ISSN: 1079-9893 (Print) Linking ISSN: 10799893 NLM ISO Abbreviation: J Recept Signal Transduct Res Subsets: MEDLINE |
| أسماء مطبوعة: | Publication: London : Informa Healthcare Original Publication: New York, NY : Marcel Dekker, Inc., c1995- |
| مواضيع طبية MeSH: | Adrenergic beta-Agonists/*pharmacology , Isoproterenol/*pharmacology , Muscle, Skeletal/*physiology , Receptors, Adrenergic, beta/*physiology, Adrenergic beta-Antagonists/pharmacology ; Animals ; CHO Cells ; Cell Membrane/physiology ; Cricetinae ; Down-Regulation/drug effects ; Humans ; Iodine Radioisotopes ; Iodocyanopindolol/pharmacology ; Protein Binding ; Rats ; Time Factors |
| مستخلص: | We examined the effect of duration of beta 2-adrenergic receptor (beta 2AR) occupancy by isoproterenol on specific binding of 125I-lodocyanopindolol (125I-ICYP) in membranes from rat L6 myoblasts. Ten minute exposure caused a time-and concentration-dependent maximal decrease in 125I-ICYP binding 24 hours after exposure equal to that following continuous exposure (p < 0.05). Low temperature, concanavalin A, H89 and ICl 118,551 blocked the decline in 125I-ICYP binding during the first hour following exposure probably representing receptor sequestration to a compartment or change to a form incapable of ligand binding. Compared to controls, receptor binding 4 and 24 hours following exposure was reduced 56 +/- 8.7% and 72 +/- 8.8%, respectively (p < 0.05), and was blocked by ICl 118,551 but not CGP12177. Isoproterenol-induced, but not forskolin-stimulated, cAMP accumulation was reduced 35% 24 hours following exposure (p < 0.05). 125I-ICYP binding in intact L6 cells 4 and 24 hours after exposure were respectively 56 +/- 8.9 and 61 +/- 13% of controls (p < 0.05). Following agonist exposure, CHO cell membranes expressing human beta 2ARs exhibited 125I-ICYP binding 85 +/- 2.0% and 6 +/- 2.8% of control values 4 and 24 hours, respectively (p < 0.05). A model predicting that full occupation of the beta 2AR activates receptor degradation explains our results that agonist-induced down-regulation of beta 2AR does not require continuous presence of the agonist. |
| معلومات مُعتمدة: | GM-50979 United States GM NIGMS NIH HHS |
| المشرفين على المادة: | 0 (Adrenergic beta-Agonists) 0 (Adrenergic beta-Antagonists) 0 (Iodine Radioisotopes) 0 (Receptors, Adrenergic, beta) 83498-72-0 (Iodocyanopindolol) L628TT009W (Isoproterenol) |
| تواريخ الأحداث: | Date Created: 19990601 Date Completed: 19990722 Latest Revision: 20131121 |
| رمز التحديث: | 20231215 |
| DOI: | 10.3109/10799899909042876 |
| PMID: | 10349597 |
| قاعدة البيانات: | MEDLINE |
PDF full text from Publisher | تدمد: | 1079-9893 |
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| DOI: | 10.3109/10799899909042876 |