Am J Physiol Cell Physiol AJP: Gastrointestinal and Liver Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Cell Physiol 279: C785-C796, 2000;
0363-6143/00 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (9)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Obara, K.
Right arrow Articles by Paul, R. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Obara, K.
Right arrow Articles by Paul, R. J.
Vol. 279, Issue 3, C785-C796, September 2000

Effects of microtubules and microfilaments on [Ca2+]i and contractility in a reconstituted fibroblast fiber

Kazuo Obara1, Koji Nobe1, Hiromi Nobe1, Michael S. Kolodney2, Primal De Lanerolle3, and Richard J. Paul1

1 Departments of Physiology and Biophysics, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267; 3 College of Medicine, University of Illinois at Chicago, Chicago, Illinois 60612; and 2 Dermatology Division, Department of Medicine, University of California at Los Angeles, Los Angeles, California 90095

We used a reconstituted fiber formed when 3T3 fibroblasts are grown in collagen to characterize nonmuscle contractility and Ca2+ signaling. Calf serum (CS) and thrombin elicited reversible contractures repeatable for >8 h. CS elicited dose-dependent increases in isometric force; 30% produced the largest forces of 106 ± 12 µN (n = 30), which is estimated to be 0.5 mN/mm2 cell cross-sectional area. Half times for contraction and relaxation were 4.7 ± 0.3 and 3.1 ± 0.3 min at 37°C. With imposition of constant shortening velocities, force declined with time, yielding time-dependent force-velocity relations. Forces at 5 s fit the hyperbolic Hill equation; maximum velocity (Vmax) was 0.035 ± 0.002 Lo/s. Compliance averaged 0.0076 ± 0.0006 Lo/Fo. Disruption of microtubules with nocodazole in a CS-contracted fiber had no net effects on force, Vmax, or stiffness; force increased in 8, but decreased in 13, fibers. Nocodazole did not affect baseline intracellular Ca2+ concentration ([Ca2+]i) but reduced (~30%) the [Ca2+]i response to CS. The force after nocodazole treatment was the primary determinant of stiffness and Vmax, suggesting that microtubules were not a major component of fiber internal mechanical resistance. Cytochalasin D had major inhibitory effects on all contractile parameters measured but little effect on [Ca2+]i.

cytochalasin D; nocodazole; nonmuscle mechanics; Swiss 3T3; tensegrity; intracellular calcium concentration


This article has been cited by other articles:


Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
H. H. Wang, H. Tanaka, X. Qin, T. Zhao, L.-H. Ye, T. Okagaki, T. Katayama, A. Nakamura, R. Ishikawa, S. E. Thatcher, et al.
Blebbistatin inhibits the chemotaxis of vascular smooth muscle cells by disrupting the myosin II-actin interaction
Am J Physiol Heart Circ Physiol, May 1, 2008; 294(5): H2060 - H2068.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
H. Nobe, K. Nobe, and R. J. Paul
Fibroblast fiber contraction: role of C and Rho kinase in activation by thromboxane A2
Am J Physiol Cell Physiol, December 1, 2003; 285(6): C1411 - C1419.
[Abstract] [Full Text] [PDF]

Home page
 J. Cell Sci.Home page
D. E. Ingber
Tensegrity I. Cell structure and hierarchical systems biology
J. Cell Sci., April 1, 2003; 116(7): 1157 - 1173.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
T. M. Seasholtz
The RHOad less traveled: the myosin phosphorylation-independent path from Rho kinase to cell contraction. : Focus on "Rho kinase mediates serum-induced contraction in fibroblast fibers independent of myosin LC20 phosphorylation"
Am J Physiol Cell Physiol, March 1, 2003; 284(3): C596 - C598.
[Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
H. Nobe, K. Nobe, F. Fazal, P. de Lanerolle, and R. J. Paul
Rho kinase mediates serum-induced contraction in fibroblast fibers independent of myosin LC20 phosphorylation
Am J Physiol Cell Physiol, March 1, 2003; 284(3): C599 - C606.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online