Characteristics Of Skeletal Muscle

1.1 Background

BUAA Academic Dissertation for Master’s Degree

1 Introduction

Muscle is a very specialized tissue that has both the ability to contract and the ability to conduct electrical impulses. Muscle fiber generates tension through the action of actin and myosin cross-bridge cycling. The muscle may shorten, lengthen or remain the same under tension. Skeletal muscle has an impressive ability to regenerate itself, which it does on a daily basis as well as in response to injury [1].

1.1.1 Characteristic Of Skeletal Muscle

Muscle is a very specialized tissue that has both the ability to contract and the ability to conduct electrical impulses. Muscles are classified both structurally as either striated or smooth and functionally as either voluntary or involuntary and. Muscle cells (myocytes) are elongated and classified as either striated muscle cells or smooth muscle cells depending on the presence or absence of regularly repeated arrangements of myofibrillar contractile proteins called myofilaments.

Muscle tissue can be described as three different types: 1. Skeletal muscle - is used to effect skeletal movement such as locomotion and in maintaining posture 2. Smooth muscle – it is found within the walls of organs and structures such as the stomach, intestines, etc. 3. Cardiac muscle – it is found only in the heart

Figure 1. Types of muscle.

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Chapter 1 Introduction

Skeletal muscle is striated muscle tissue that is attached to bones. It is composed of fibers that look like a mixture of dark and light bands bundled together that run along the bone. These muscles are responsible for relaxing and contracting when a person moves. Skeletal muscles are the muscles that can be seen and feel through our skin.

A muscle fiber is a multi-...

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...nt of C2C12 myoblasts into myotubes. FN line width was varied as 20, 50, 100 and 200 lm and line spacing was varied as 10, 20 and 30 lm, which with inclusion of an isotropic control resulted in 13 different surface conditions. Differentiated myotubes were labeled for MHC (red) and nuclei with DAPI (blue). At the 10 lm spacing, myotubes were able to overgrow the gap between FN lines and form a sheet that was aligned off-axis to the underlying FN pattern. At the larger spacings of 20 and 30 lm, the myotubes remained restricted to the patterned FN area, but, at larger line widths such as 200 lm, the myotubes were also aligned off-axis to the underlying FN pattern. In all conditions, myotubes on patterned surfaces demonstrated increased alignment compared with the isotropic control. Scale bar is 200 lm.

1.2.2 Parallel Nanofibers surface area coverage (Fig. 3A). The 20