scholarly journals Mechanisms of regulation electric and contractile activity smooth muscle cells: the role of cytoskeleton

2008 ◽  
Vol 7 (4) ◽  
pp. 31-37
Author(s):  
M. A. Medvedev ◽  
M. B. Baskakov ◽  
S. V. Gusakova ◽  
I. V. Kovalyov ◽  
O. S. Melnik ◽  
...  

The influence of modulation of cytoskeleton by colchicine, vinblastine, cytochalasine B and docetaxel on contractile reactions of smooth muscle cells caused by electric stimulus, depolarization, phenylephrine has been investigated by the mechanographical method, by the methods of the double sucrose gup junction. It is established, that induced by a isoosmotic hyperpotassium solution of reduction of smooth muscle of the rat’s aorta, and also caused depolarization stimulus potentials of action and reductions smooth muscle cells from guinea pig urethra, depend more on the condition of microfilaments cytoskeleton than on microtubules. The reduction of smooth muscles cells of an aorta of the rat, caused by isoosmotic striction, is suppressed under the destruction microfilaments whereas the reduction in a hyperosmotic solution depends on a condition of both microfilaments, and microtubules. Cytoskeleton’s microfilaments of aorta’s smooth muscles and microtubules of smooth muscles of cells ureter are involved in mechanisms of action phenylephrine’s action on contractile activity of smooth muscle cells of an aorta and ureter.

2009 ◽  
Vol 8 (4) ◽  
pp. 41-46
Author(s):  
I. V. Kovalyev ◽  
S. V. Gusakova ◽  
O. S. Melnik ◽  
M. B. Baskakov ◽  
L. V. Kapilevich ◽  
...  

The influence of of hydrogen peroxide on the contractile reactions of smooth muscle cells caused by hyperpotassium solution end phenylephrine in modulation a potassium conductance the membrane and the state of cytoskeleton elements has been investigated by the mechanographical method. It has multidirectional influence of hydrogen peroxide in the reduction of smooth muscles of rat aorta with the membrane depolarization hyperpotassium solution and action phenylephrine: phenylephrine decline in value and increase strength hyperpotassium contractures. We show that the cytoskeleton components involved in the mechanisms of action of hydrogen peroxide in the contractile reactions of smooth muscles of rat aorta caused by phenylephrine.


2012 ◽  
Vol 11 (6) ◽  
pp. 51-58 ◽  
Author(s):  
I. V. Kovalyov ◽  
M. B. Baskakov ◽  
S. V. Gusakova ◽  
T. A. Vtorushina ◽  
A. S. Zheludeva ◽  
...  

2010 ◽  
Vol 9 (6) ◽  
pp. 12-17
Author(s):  
M. B. Baskakov ◽  
S. V. Gusakova ◽  
A. S. Zheludeva ◽  
L. V. Smagly ◽  
I. V. Kovalyov ◽  
...  

In preparations of rat aorta, used as a model of muscular type arteries, the method mehanografii studied the effect of hydrogen sulfide on the reduction of isolated of vascular smooth muscle. Found that hydrogen sulfide in concentrations 1—50 mmol increases the mechanical stress of smooth muscle in high-K + medium. At higher concentrations (300—1 000 mmol) H2S leads to lower amplitude giperkalievoy contraction in high-K + medium. Reduction of smooth muscle cells caused by phenylephrine inhibited the action of hydrogen sulfide in the whole range of concentrations. The causes of differences in data obtained with the results of studies in other laboratories, and possible mechanisms of action of hydrogen sulfide on the contractile activity of vascular smooth muscle.


2015 ◽  
Vol 308 (7) ◽  
pp. G625-G633 ◽  
Author(s):  
Ji Yeon Lee ◽  
Eun-ju Ko ◽  
Ki Duck Ahn ◽  
Sung Kim ◽  
Poong-Lyul Rhee

Changes in resting membrane potential (RMP) regulate membrane excitability. K+ conductance(s) are one of the main factors in regulating RMP. The functional role of K+ conductances has not been studied the in human gastric corpus smooth muscles (HGCS). To examine the role of K+ channels in regulation of RMP in HGCS we employed microelectrode recordings, patch-clamp, and molecular approaches. Tetraethylammonium and charybdotoxin did not affect the RMP, suggesting that BK channels are not involved in regulating RMP. Apamin, a selective small conductance Ca2+-activated K+ channel (SK) blocker, did not show a significant effect on the membrane excitability. 4-Aminopyridine, a Kv channel blocker, caused depolarization and increased the duration of slow wave potentials. 4-Aminopyridine also inhibited a delayed rectifying K+ current in isolated smooth muscle cells. End-product RT-PCR gel detected Kv1.2 and Kv1.5 in human gastric corpus muscles. Glibenclamide, an ATP-sensitive K+ channel (KATP) blocker, did not induce depolarization, but nicorandil, a KATP opener, hyperpolarized HGCS, suggesting that KATP are expressed but not basally activated. Kir6.2 transcript, a pore-forming subunit of KATP was expressed in HGCS. A low concentration of Ba2+, a Kir blocker, induced strong depolarization. Interestingly, Ba2+-sensitive currents were minimally expressed in isolated smooth muscle cells under whole-cell patch configuration. KCNJ2 (Kir2.1) transcript was expressed in HGCS. Unique K+ conductances regulate the RMP in HGCS. Delayed and inwardly rectifying K+ channels are the main candidates in regulating membrane excitability in HGCS. With the development of cell dispersion techniques of interstitial cells, the cell-specific functional significance will require further analysis.


1998 ◽  
Vol 76 (7-8) ◽  
pp. 802-806 ◽  
Author(s):  
J Noireaud ◽  
O Souilem ◽  
S Baudet ◽  
J -C Bidon ◽  
M Gogny ◽  
...  

Smooth muscles hyperresponsiveness is a common feature in anaphylaxis and allergic diseases. The aim of the present work was to investigate whether the enhanced reactivity of sensitized guinea-pig vas deferens was associated with changes in the resting membrane potential (Er) of the smooth muscle cells. Active sensitization was performed by subcutaneous injection of egg albumen. Er was measured in vitro in isolated vas deferens with conventional KCl-filled microelectrodes. Quantification of [3H]ouabain binding sites, measurements of 86Rb efflux, and measurements of Na and K contents were also performed. In normal physiological solution, at 35°C, Er was a mean of -54.1 ± 0.3 mV (mean ± SEM) in control vas deferens. Sensitization resulted in depolarizing Er by about 7 mV. In control and sensitized preparations, the 3H-ouabain binding site concentration, the efflux of 86Rb, and the K content were similar. In guinea-pig vas deferens, active sensitization induced a partial depolarization of the resting membrane potential of the smooth muscle cells, which did not result from a downregulation of Na+-K+ pump sites.Key words: hyperreactivity, sensitization, Na+-K+ ATPase, guinea-pig, vas deferens, smooth muscle.


1968 ◽  
Vol 37 (3) ◽  
pp. 794-817 ◽  
Author(s):  
Neil C. R. Merrillees

Smooth muscle cells of the external longitudinal coat of the guinea pig vas deferens were followed for 480 µ at 4.5-µ intervals. Muscle bundles and fibers interwove, facilitating intermuscular and neuromuscular contacts. The ribbon- or rodlike muscle cells were about 450 µ long, 3,000 µ3 in volume, and 4,500 µ2 in area. The thickened nuclear zone lay anywhere along the middle one-third of the cell. Intercellular distances were 500–800 A. Intrusions were rare, and tight-junctions absent. At any level in a field of 80 muscle fibers there were 10–15 nerve bundles, each containing several varicose axons. Bundles and axons divided. Axons, en passage, were frequently within 500–1,000 A of a muscle fiber. En passage close contacts were rate. Axon terminations were bare, and bare axons invariably terminated. Bare terminations had scattered vesicle-laden varicosities and were from 10µ-60 µ in length, and all ended within 500 A of muscle fibers. Some made close contact with muscle fibers. Less than half of the muscle cells received this close contact, but some cells were approached by more than one termination. Most terminations involved more than one cell. Some cells had little or no innervation. Some groups of cells had a rich innervation. There was very little evidence of sensory innervation. These conclusions are not valid for other smooth muscles.


2000 ◽  
Vol 84 (4) ◽  
pp. 431-437 ◽  
Author(s):  
Toshihiro Unno ◽  
Tadafumi Inaba ◽  
Hidenori Ohashi ◽  
Tadashi Takewaki ◽  
Seiichi Komori

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