caa a22 4500 477120539 CHVBK 20180405111635.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00408650 doi (NATIONALLICENCE)springer-10.1007/BF00408650 Regulation of β-adrenoceptor properties and the lipid milieu in heart muscle membranes during stress [Elektronische Daten] [Sigmundur Gudbjamason, V. Benediktsdottir] The purpose of this study was to examine changes in fatty acyl chain composition of major cardiac phospholipids in relation to down-regulation of β-adrenoceptors during various forms of stress or chronic adrenergic stimulation. Analysis of the fatty acid profile of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) in sarcolemma or cardiac muscle membranes showed partial replacement of 18:2n-6 by 20:4n-6 in PC and replacement of both 18:2n-6 and 20:4n-6 by 22:6n-3 in PE during daily administration of epinephrine or norepinephrine for 7 or 15 days, respectively These changes in membrane PC and PE coincided with down-regulation or the decrease in Bmax of β-adrenoceptors during adrenergic stimulation. Cardiac membrane response to other forms of stress or chronic adrenergic stimulation such as neonatal stress, restriction stress or restricted food intake was expressed in the same way, that is replacement of 18:2n-6 by 20:4n-6 in PC and replacement of 18:2n-6 and 20:4n-6 by 22:6n-3 in PE. Conclusion: Adaptation to stress includes a decrease in the density of binding sites or down-regulation of β-adrenoceptors in sarcolemma synchronized with specific alterations in the fatty acyl chain composition within the membrane bilayer. The changes in the lipid milieu of the membrane may facilitate conformational changes in the transmembrane segment of the receptor forming the ligand binding sites of the β-adrenoceptor. Kluwer Academic Publishers, 1996 β-Adrenoceptors nationallicence down-regulation nationallicence stress-adaptation nationallicence linoleic acid nationallicence arachidonic acid nationallicence docosahexacnoic acid nationallicence Gudbjamason Sigmundur Science Institute, University of Iceland, Dunhaga 3, IS-107, Reykjavik, Iceland aut Benediktsdottir V. Science Institute, University of Iceland, Dunhaga 3, IS-107, Reykjavik, Iceland aut Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www.wkap.nl 163-164/1(1996-03-01), 137-143 0300-8177 163-164:1<137 1996 163-164 11010 https://doi.org/10.1007/BF00408650 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00408650 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gudbjamason Sigmundur Science Institute, University of Iceland, Dunhaga 3, IS-107, Reykjavik, Iceland aut NATIONALLICENCE 700 1- Benediktsdottir V. Science Institute, University of Iceland, Dunhaga 3, IS-107, Reykjavik, Iceland aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Kluwer Academic Publishers; http://www.wkap.nl 163-164/1(1996-03-01), 137-143 0300-8177 163-164:1<137 1996 163-164 11010 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer