scholarly journals Diabetic GK Rat Plasma but Not Normal Wistar Rat Plasma Induces Insulin-Stimulated DNA Synthesis in Primary Cultured Smooth Muscle Cells in GK Rat Aorta

1994 ◽  
Vol 64 (3) ◽  
pp. 195-200 ◽  
Author(s):  
Ikuko Kimura ◽  
Youichi Nakano ◽  
Takeshi Naitoh ◽  
Motonori Okabe ◽  
Masayasu Kimura
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Dna Synthesis ◽  
Muscle Cells ◽  
Wistar Rat ◽  
Rat Aorta ◽  
Rat Plasma ◽  
Gk Rat ◽  
Cultured Smooth Muscle Cells

Autocrine Induction of DNA Synthesis by Mechanical Injury of Cultured Smooth Muscle Cells

1996 ◽  
Vol 16 (2) ◽  
pp. 187-193 ◽  
Author(s):  
Federico Calara ◽  
Sean Ameli ◽  
Anna Hultgårdh-Nilsson ◽  
Bojan Cercek ◽  
Joel Kupfer ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Dna Synthesis ◽  
Muscle Cells ◽  
Mechanical Injury ◽  
Cultured Smooth Muscle Cells

Ca-activated K channel in cultured smooth muscle cells of rat aortic media

1988 ◽  
Vol 255 (3) ◽  
pp. H410-H418 ◽  
Author(s):  
J. Sadoshima ◽  
N. Akaike ◽  
H. Tomoike ◽  
H. Kanaide ◽  
M. Nakamura
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Rat Aorta ◽  
K Channel ◽  
Patch Clamp Technique ◽  
Intracellular Ca ◽  
Aortic Media ◽  
Cultured Smooth Muscle Cells ◽  
Low Sensitivity

Electrical and pharmacological properties of the single Ca-activated K channel in cultured smooth muscle cells (SMC) of the rat aorta were studied with the patch-clamp technique. The Ca-activated K channel had a slope conductance (gamma K) of 135 +/- 2 pS (mean +/- SE; n = 5) in symmetrical 142 mM K solutions. The reversal potentials show a 56-mV change for a 10-fold change in the external K concentration. Probability of the channel opening increased when the intracellular Ca concentration ([Ca]i) was increased over 10(-7) M or the membrane was depolarized. The channel was blocked by either external tetraethylammonium (TEA, 10–30 mM) or by internal Ba (1–5 mM). Channel activities were characterized by burst-like openings. Open-time histogram was fitted with a single exponential (tau = 1.3 ms at +10 mV and 10(-7) M [Ca]i), whereas the closed-time histogram was fitted with two exponentials (tau 1 = 0.7 ms and tau 2 = 111 ms). The permeability ratio for monovalent cations calculated with the Goldman-Hodgkin-Katz equation was K:Rb:Na = 1:0.7: less than 0.01. We conclude from these observations that the Ca-activated K channel in cultured SMC of the rat aorta is characterized by a middle size gamma K, activation by [Ca]i increase and depolarization, relatively low sensitivity to TEA, and high selectivity for K ions.

Cyclic AMP modulates Ca-activated K channel in cultured smooth muscle cells of rat aortas

1988 ◽  
Vol 255 (4) ◽  
pp. H754-H759 ◽  
Author(s):  
J. Sadoshima ◽  
N. Akaike ◽  
H. Kanaide ◽  
M. Nakamura
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Rat Aorta ◽  
K Channel ◽  
Free Calcium ◽  
Bathing Solution ◽  
Patch Clamp Technique ◽  
K Channels ◽  
Cultured Smooth Muscle Cells

Effects of adenosine 3',5'-cyclic monophosphate (cAMP) on single Ca-activated K current (IK(Ca)) in cultured smooth muscle cells of the rat aorta were investigated with the patch-clamp technique. In cell-attached patch configurations, extracellular application of isoproterenol (10(-5) M) increased the Ca-activated K currents. The increase in the currents was due to an increase in the probability of channel openings (Po). Neither unit conductance nor the maximum number of the channel in the patch was affected by the drug. The effects were inhibited by adding propranolol (10(-6) M). The extracellular application of forskolin (10(-5) M) or dibutyryl cAMP (10(-4) M) mimicked the effects of isoproterenol. In inside-out patch configurations, activated cAMP-dependent protein kinase (A kinase) in the bathing solution increased the sensitivity of the Ca-activated K channels to intracellular free calcium concentration ([Ca]i) and enhanced Po. Kinetic analyses of the IK(Ca) showed that cAMP-dependent phosphorylation of the Ca-activated K channels significantly reduced the mean closed time between bursting openings. We conclude from these observations that the Ca-activated K channels in aortic cells may increase Po through cAMP-dependent phosphorylation.

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