Cardiomyocyte Membrane Structure and cAMP Compartmentation Produce Anatomical Variation in β2AR-cAMP Responsiveness in Murine Hearts.
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ABSTRACT:
SUBMITTER: Wright PT
PROVIDER: S-EPMC5912947 | biostudies-literature | 2018 Apr
REPOSITORIES: biostudies-literature
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Cardiomyocyte Membrane Structure and cAMP Compartmentation Produce Anatomical Variation in β<sub>2</sub>AR-cAMP Responsiveness in Murine Hearts.
Wright Peter T PT Bhogal Navneet K NK Diakonov Ivan I Pannell Laura M K LMK Perera Ruwan K RK Bork Nadja I NI Schobesberger Sophie S Lucarelli Carla C Faggian Giuseppe G Alvarez-Laviada Anita A Zaccolo Manuela M Kamp Timothy J TJ Balijepalli Ravi C RC Lyon Alexander R AR Harding Sian E SE Nikolaev Viacheslav O VO Gorelik Julia J
Cell reports 20180401 2
Cardiomyocytes from the apex but not the base of the heart increase their contractility in response to β<sub>2</sub>-adrenoceptor (β<sub>2</sub>AR) stimulation, which may underlie the development of Takotsubo cardiomyopathy. However, both cell types produce comparable cytosolic amounts of the second messenger cAMP. We investigated this discrepancy using nanoscale imaging techniques and found that, structurally, basal cardiomyocytes have more organized membranes (higher T-tubular and caveolar den ...[more]
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