scholarly journals Differential Effects of Carcinogens on Hepatic Cytosolic Cyclic AMP-dependent Protein Kinase Activity

1986 ◽  
Vol 5 (4) ◽  
pp. 267-273
Author(s):  
C. Timchalk ◽  
A. K. Charles
Keyword(s):  
Protein Kinase ◽  
Kinase Activity ◽  
Activity Ratio ◽  
Cell Membrane Permeability ◽  
Protein Kinase Activity ◽  
Dependent Protein Kinase ◽  
Differential Effects ◽  
Camp Dependent Protein Kinase ◽  
Dependent Protein

Differential effects of epigenetic tumor promoters and a genotoxic carcinogen on hepatic cytosolic cyclic adenosine 3′,5′-monophosphate-dependent protein kinase (CAMP-PK) were studied in vitro, since this enzyme is one of the major mediators of cell membrane permeability. Mirex (dodecachlorooctahydro-1,3,4-metheno-2H-cyclobuto[cd]pentalene), like phorbol ester TPA (12-0-tetradecanoylphorbol-13-acetste), caused significant inhibition of cAMP-dependent protein kinase activity ratio, whereas DDT [p, p′-trichlorobis(p-chlorophenyl)ethane] produced concentration-dependent changes. Diethylnitrosamine (DEN) and phenobarbitol (PB), however, showed a significant enhancement of the activity ratio. Interestingly, combinations of mirex, DDT with PB or DEN resulted in the potentiation of CAMP-dependent protein kinase activity in contrast to their effects when used separately. The results suggest that the influences of mirex and TPA in vitro on CAMP-PK are different from those observed in other cell and intact animal systems.

Involvement of cAMP-dependent protein kinase in the regulation of heart contractile force. II

1979 ◽  
Vol 236 (1) ◽  
pp. H84-H91
Author(s):  
S. L. Keely ◽  
A. Eiring
Keyword(s):  
Protein Kinase ◽  
Kinase Activity ◽  
Activity Ratio ◽  
Contractile Force ◽  
Protein Kinase Activity ◽  
Phosphorylase Activity ◽  
Dependent Protein Kinase ◽  
Guinea Pig Heart ◽  
Camp Dependent Protein Kinase ◽  
Dependent Protein

The effects of histamine on heart cAMP-dependent protein kinase activity, cAMP levels, phosphorylase activity, and contractile force was investigated in the perfused guinea pig heart. To accurately determine the protein kinase activity ratio in guinea pig heart, it was necessary to measure kinase activity in whole homogenates immediately after homogenization of the tissue. Histamine produced a rapid dose-dependent increase in cAMP and the protein kinase activity ratio followed by increased in contractile force and phosphorylase activity. There was a good correlation between the degree of protein kinase activation and the increase in phosphorylase and force. The beta-adrenergic blocking agent propranolol did not reduce the effects of histamine, but metiamide, a potent H2-receptor antagonist, greatly attenuated all the effects of histamine. The data support the hypothesis that increases in heart cAMP-dependent protein kinase activity produce corresponding increases in contractile force and phosphorylase activity.

Analytical subcellular distribution of cAMP-dependent protein kinase activity in bull sperm

1984 ◽  
Vol 10 (4) ◽  
pp. 433-444 ◽  
Author(s):  
Claude C. Pariset ◽  
Jacqueline S. Weinman ◽  
Francoise T. Escaig ◽  
Michele Y. Guyot ◽  
Francine C. Iftode ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Subcellular Distribution ◽  
Kinase Activity ◽  
Protein Kinase Activity ◽  
Dependent Protein Kinase ◽  
Camp Dependent Protein Kinase ◽  
Dependent Protein ◽  
Bull Sperm

scholarly journals Imaging of cAMP-dependent protein kinase activity in living neural cells using a novel fluorescent substrate

FEBS Letters ◽  
1997 ◽  
Vol 414 (1) ◽  
pp. 55-60 ◽  
Author(s):  
Hideyoshi Higashi ◽  
Kazuki Sato ◽  
Atsuko Ohtake ◽  
Akira Omori ◽  
Sachiyo Yoshida ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Kinase Activity ◽  
Protein Kinase Activity ◽  
Neural Cells ◽  
Dependent Protein Kinase ◽  
Fluorescent Substrate ◽  
Camp Dependent Protein Kinase ◽  
Dependent Protein

Relaxing effect of pharmacologic interventions increasing cAMP in rat heart

1981 ◽  
Vol 240 (4) ◽  
pp. H441-H447
Author(s):  
L. Vittone ◽  
A. Grassi ◽  
L. Chiappe ◽  
M. Argel ◽  
H. E. Cingolani
Keyword(s):  
Protein Kinase ◽  
Rat Heart ◽  
Kinase Activity ◽  
Isolated Rat Heart ◽  
Protein Kinase Activity ◽  
Dependent Protein Kinase ◽  
Camp Dependent Protein Kinase ◽  
High Calcium ◽  
Dependent Protein ◽  
Camp Levels

The relationship between cAMP and relaxation was studied in the isolated rat heart beating at constant rate and perfused at constant coronary flow. After treatment during 1 min with different positive inotropic interventions, cyclic nucleotide levels (cAMP and cGMP) and cAMP-dependent protein kinase activity were determined in heart homogenates. Glucagon, norepinephrine, and isoproterenol increased cAMP from 0.503 +/- 0.025 pmol/mg wet wt to 1.051 +/- 0.099, 0.900 +/- 0.064, and 0.982 +/- 0.138, respectively. Simultaneously glucagon, norepinephrine, and isoproterenol increased cAMP-dependent protein kinase activity ratio from 0.21 +/- 0.02 to 0.45 +/- 0.04, 0.33 +/- 0.02, and 0.34 +/- 0.02, respectively. The ratio between maximal velocities of contraction and relaxation (+T/-T) was significantly decreased by these interventions, whereas time to peak tension (TTP) was shortened by norepinephrine and isoproterenol. High calcium, ouabain, and paired stimulation did not affect cAMP levels, TTP, or +T/-T. A striking correlation was found between cAMP-dependent protein kinase activity and relaxation induces, i.e., TTP, -T, or +T/-T (r = +/- 0.7 to -0.9). Results suggest that inotropic interventions increasing cAMP levels might be primarily affecting intracellular mechanisms causing relaxation.

Biochemical changes accompanying enhanced cardiac contractility by ionophore A23187

1985 ◽  
Vol 249 (6) ◽  
pp. H1204-H1210 ◽  
Author(s):  
J. J. Murray ◽  
P. W. Reed ◽  
J. G. Dobson
Keyword(s):  
Protein Kinase ◽  
Protein Kinases ◽  
Kinase Activity ◽  
Protein Kinase Activity ◽  
Ionophore A23187 ◽  
Phosphorylase Activity ◽  
Dependent Protein Kinase ◽  
Camp Content ◽  
Camp Dependent Protein Kinase ◽  
Dependent Protein

We have reported that the divalent cation ionophore A23187, like the beta-adrenergic agonist isoproterenol, increased the force of contraction and rate of relaxation and shortened the duration of contraction of papillary muscles isolated from guinea pigs. A23187 produced a fall in resting tension and decreased the contracture tension of K +/- depolarized muscles, as did isoproterenol. In the present studies, isoproterenol produced a concentration-dependent, rapid, and sustained increase in the cyclic AMP (cAMP) content of papillary muscle. In contrast, A23187 had no detectable effect on cAMP levels, even in the presence of the phosphodiesterase inhibitor, papaverine. Neither drug, at concentrations maximal for contractile effects, altered cyclic GMP (cGMP). Isoproterenol increased the cAMP-dependent protein kinase activity ratio, whereas A23187 did not change the activity of this enzyme. However, both A23187 and isoproterenol produced a concentration-dependent increase in phosphorylase activity. Concentrations of A23187 or isoproterenol that enhanced contractility maximally increased the alkali-labile phosphate (by ca. 35%) but were without effect on the acid-labile, alkali-stable phosphate in the total acid precipitable protein. Contractile effects of isoproterenol, which reflect activated Ca2+ uptake, and the increase in phosphorylase activity produced by this agent are believed to be due to an increase in cAMP with subsequent activation of cAMP-dependent protein kinases and phosphorylation of proteins. A23187 may produce similar contractile effects without an increase in cAMP or cAMP-dependent protein kinase activity by activating other protein kinases and/or inhibiting phosphoprotein phosphatases, most likely by its effects on intracellular calcium.

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