Models of contractile units and their assembly in smooth muscle

被引:12
作者
Ali, F
Paré, PD
Seow, CY [1 ]
机构
[1] Univ British Columbia, Dept Pathol & Lab Med, Vancouver, BC V6Z 1Y6, Canada
[2] Univ British Columbia, James Hogg iCAPTURE Ctr Cardiovasc & Pulm Res, Vancouver, BC V6Z 1Y6, Canada
[3] Univ British Columbia, Dept Expt Med, Vancouver, BC V6Z 1Y6, Canada
关键词
contraction model; ultrastructure; length adaptation; plasticity;
D O I
10.1139/Y05-052
中图分类号
R9 [药学];
学科分类号
1007 ;
摘要
It is believed that the contractile filaments in smooth muscle are organized into arrays of contractile units (similar to the sarcomeric structure in striated muscle), and that such an organization is crucial for transforming the mechanical activities of actomyosin interaction into cell shortening and force generation. Details of the filament organization, however, are still poorly understood. Several models of contractile filament architecture are discussed here. To account for the linear relationship observed between the force generated by a smooth muscle and the muscle length at the plateau of an isotonic contraction, a model of contractile unit is proposed. The model consists of 2 dense bodies with actin (thin) filaments attached, and a myosin (thick) filament lying between the parallel thin filaments. In addition, the thick filament is assumed to span the whole contractile unit length, from dense body to dense body, so that when the contractile unit shortens, the amount of overlap between the thick and thin filaments (i.e., the distance between the dense bodies) decreases in exact proportion to the amount of shortening. Assembly of the contractile units into functional contractile apparatus is assumed to involve a group of cells that form a mechanical syncytium. The contractile apparatus is assumed malleable in that the number of contractile units in series and in parallel can be altered to accommodate strains on the muscle and to maintain the muscle's optimal mechanical function.
引用
收藏
页码:825 / 831
页数:7
相关论文
共 40 条
[11]   The first three minutes: smooth muscle contraction, cytoskeletal events, and soft glasses [J].
Gunst, SJ ;
Fredberg, JJ .
JOURNAL OF APPLIED PHYSIOLOGY, 2003, 95 (01) :413-425
[12]   MECHANISMS FOR THE MECHANICAL PLASTICITY OF TRACHEAL SMOOTH-MUSCLE [J].
GUNST, SJ ;
MEISS, RA ;
WU, MF ;
ROWE, M .
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 1995, 268 (05) :C1267-C1276
[13]   FORCE-VELOCITY AND SERIES ELASTIC CHARACTERISTICS OF SMOOTH-MUSCLE FROM HOG CAROTID-ARTERY [J].
HERLIHY, JT ;
MURPHY, RA .
CIRCULATION RESEARCH, 1974, 34 (04) :461-466
[14]   'Sarcomeres' of smooth muscle:: functional characteristics and ultrastructural evidence [J].
Herrera, AM ;
McParland, BE ;
Bienkowska, A ;
Tait, R ;
Paré, PD ;
Seow, CY .
JOURNAL OF CELL SCIENCE, 2005, 118 (11) :2381-2392
[15]   Electron microscopic study of actin polymerization in airway smooth muscle [J].
Herrera, AM ;
Martinez, EC ;
Seow, CY .
AMERICAN JOURNAL OF PHYSIOLOGY-LUNG CELLULAR AND MOLECULAR PHYSIOLOGY, 2004, 286 (06) :L1161-L1168
[16]   Influence of calcium on myosin thick filament formation in intact airway smooth muscle [J].
Herrera, AM ;
Kuo, KH ;
Seow, CY .
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 2002, 282 (02) :C310-C316
[17]   The heat of shortening and the dynamic constants of muscle [J].
Hill, AV .
PROCEEDINGS OF THE ROYAL SOCIETY SERIES B-BIOLOGICAL SCIENCES, 1938, 126 (843) :136-195
[18]   THE STRUCTURE OF THE CONTRACTILE APPARATUS IN ULTRARAPIDLY FROZEN SMOOTH-MUSCLE - FREEZE-FRACTURE, DEEP-ETCH, AND FREEZE-SUBSTITUTION STUDIES [J].
HODGKINSON, JL ;
NEWMAN, TM ;
MARSTON, SB ;
SEVERS, NJ .
JOURNAL OF STRUCTURAL BIOLOGY, 1995, 114 (02) :93-104
[19]   MUSCLE STRUCTURE AND THEORIES OF CONTRACTION [J].
HUXLEY, AF .
PROGRESS IN BIOPHYSICS & MOLECULAR BIOLOGY, 1957, 7 :255-&
[20]   LOCALIZATION OF MYOSIN FILAMENTS IN SMOOTH MUSCLE [J].
KELLY, RE ;
RICE, RV .
JOURNAL OF CELL BIOLOGY, 1968, 37 (01) :105-&