Smooth Muscle Structure and Function

Smooth Muscle Structure and Function

• Dense bodies in smooth muscle are the primary sites for force transmission and anchoring of the actin filaments.
• Myosin filaments in smooth muscle generate force through their interaction with actin filaments.
• Individual contractile units in smooth muscle are arranged in a non-striated, irregular pattern.
• In smooth muscle, the diameter of myosin filaments is thicker than that of actin filaments.
• Some dense bodies in smooth muscle attach to adjacent cells through adherens junctions.
• The function of dense bodies in smooth muscle is to act as anchoring sites for actin filaments and to transmit the force generated by the contraction of the muscle.
• Structural proteins, such as vinculin and α-actinin, link the dispersed dense bodies in smooth muscle.
• Myosin filaments in smooth muscle are arranged in a helical pattern, allowing for the generation of force in multiple directions.
• The function of myosin filaments in smooth muscle is to generate force through their interaction with actin filaments.
• Dense bodies attached to the cell membrane in smooth muscle act as anchoring sites, transmitting the force generated by muscle contraction to the surrounding tissue.

Test your knowledge of the structure and arrangement of actin and myosin filaments in smooth muscle cells, including the role of dense bodies and their attachment to the sarcolemma.