Alpha-Adrenergic Regulation of Camp in Ventricular Cardiac Myocytes

alpha 1-Adrenergic regulation of phosphoinositide metabolism and protein kinase C translocation was studied in isolated rat cardiac myocytes. Exposure of [3H]inositol-labeled myocytes to norepinephrine in the presence of propranolol caused a dose-dependent increase in [3H]inositol phosphates. Norepinephrine also increased the level of membrane-associated protein kinase C from approximately 10% of total activity to 18%, with a dose response similar to that for generation of inositol phosphates. Depolarization of myocytes with 30 mM KCl had no effect on inositol phosphates or membrane-associated protein kinase C but potentiated the effect of submaximal norepinephrine on both parameters. The potentiation of protein kinase C translocation was amplified when extracellular Ca2+ was increased to 4 mM, resulting in membrane association of one-third of the total cellular activity. These data show that activation of protein kinase C occurs during alpha 1-adrenergic stimulation of cardiac myocytes and that elevation of intracellular Ca2+ amplifies this effect at least in part through increased phosphoinositide metabolism.

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β1-adrenergic regulation of rapid component of delayed rectifier K+ currents in guinea-pig cardiac myocytes

Molecular Medicine Reports ◽

10.3892/mmr.2014.2035 ◽

2014 ◽

Vol 9 (5) ◽

pp. 1923-1928 ◽

Cited By ~ 2

Author(s):

SEN WANG ◽

DI XU ◽

TING-TING WU ◽

YAN GUO ◽

YAN-HONG CHEN ◽

...

Keyword(s):

Guinea Pig ◽

Cardiac Myocytes ◽

Delayed Rectifier ◽

Adrenergic Regulation ◽

K Currents

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Cardiac myocytes cultured on a basement membrane extract of the ehs tumor

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142979 ◽

1986 ◽

Vol 44 ◽

pp. 270-271

Author(s):

L. Terracio ◽

A. Dewey ◽

K. Rubin ◽

T.K. Borg

Keyword(s):

Extracellular Matrix ◽

Basement Membrane ◽

Cardiac Myocytes ◽

Normal Tissue ◽

Cell Spreading ◽

Collagen Iv ◽

Basement Membrane Extract ◽

Membrane Extract ◽

Growth Development ◽

Multicellular Organisms

The recognition and interaction of cells with the extracellular matrix (ECM) effects the normal physiology as well as the pathology of all multicellular organisms. These interactions have been shown to influence the growth, development, and maintenance of normal tissue function. In previous studies, we have shown that neonatal cardiac myocytes specifically interacts with a variety of ECM components including fibronectin, laminin, and collagens I, III and IV. Culturing neonatal myocytes on laminin and collagen IV induces an increased rate of both cell spreading and sarcomerogenesis.

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Application of stereological analysis of cell volume to isolated myocytes in culture with and without adrenergic innervation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015962x ◽

1990 ◽

Vol 48 (3) ◽

pp. 416-417

Author(s):

Jane K. Rosenthal ◽

Dianne L. Atkins ◽

William J. Marvin ◽

Penny A. Krumm

Keyword(s):

Cardiac Myocytes ◽

Structural Changes ◽

Three Dimensional ◽

Adrenergic Innervation ◽

Culture Cell ◽

Serial Sections ◽

Newborn Rats ◽

Primary Culture Cell ◽

Biological Studies ◽

Cell Volumes

To comprehend structural changes in cardiac myocytes accompanying adrenergic innervation, it is essential that a three dimensional analysis be performed. To date, biological studies which utilize stereological methods have been limited to cells in tissue and in organs. Our laboratory has utilized current stereological techniques for measuring absolute volumes of individual myocytes in primary culture. Cell volumes are calculated for two distinct groups of cells at 96 hours in culture: isolated myocytes and myocytes innervated with adrenergic neurons (Figure 1).Cardiac myocytes are cultured from the ventricular apices of newborn rats. Cells are plated directly onto tissue culture dishes with or without preplated explants from the paravertebral thoracolumbar sympathetic chain. On day four cultures are photographed and marked for one-to-one cell location. Following conventional fixation and embeddment in eponate-12, the cells are relocated and mounted for microtomy. The cells are completely sectioned at 120nm in their parallel orientation to the surface of the dish (Figure 2). Serial sections are collected on formvar coated slotted grids and are recorded in sequence.

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