14.1 POJA-L6064+6065 Muscle spindles with nuclear bag and chain fibres
14.1 POJA-L6064+6065 Muscle spindles with nuclear bag and chain fibres
Title: Muscle spindles with nuclear bag and chain fibres
Description:
Muscle spindles in striated muscle fibres of a guinea pig (1µm plastic sections).
(A): Nuclear bag fibres.
(B): Nuclear chain fibres. (1): Striated muscle fibres. (2): Nuclear bag fibres. (3): Nuclear chain fibres. (4): Space filled with liquid surrounded by an external capsule. (5): Arteriole. (6): Nerve fibres. (A-7). Part of perimysium indicated by the blue dotted pen line.
The muscle spindle (stretch receptor) is embedded in the perimysium (connective tissue). The degree of stretching in a muscle is transformed from the spindle. There are two types of intrafusal muscle fibres dependent on the configuration of their nuclei in the middle. The nuclei either form short thin rows (nuclear chain fibres,) or occur in piles (static nuclear bag fibres). Generally, a spindle is composed of up to 4 nuclear bag fibres and up to 7-8 nuclear chain fibres. Nerve fibres are curled around the fibres and innervate the intrafusal muscle fibres.
See also:
Keywords/Mesh: locomotor system, skeletal muscle, striated muscle, proprioceptor, muscle spindle, neuromuscular spindle, histology, POJA collection
Description:
Muscle spindles in striated muscle fibres of a guinea pig (1µm plastic sections).
(A): Nuclear bag fibres.
(B): Nuclear chain fibres. (1): Striated muscle fibres. (2): Nuclear bag fibres. (3): Nuclear chain fibres. (4): Space filled with liquid surrounded by an external capsule. (5): Arteriole. (6): Nerve fibres. (A-7). Part of perimysium indicated by the blue dotted pen line.
The muscle spindle (stretch receptor) is embedded in the perimysium (connective tissue). The degree of stretching in a muscle is transformed from the spindle. There are two types of intrafusal muscle fibres dependent on the configuration of their nuclei in the middle. The nuclei either form short thin rows (nuclear chain fibres,) or occur in piles (static nuclear bag fibres). Generally, a spindle is composed of up to 4 nuclear bag fibres and up to 7-8 nuclear chain fibres. Nerve fibres are curled around the fibres and innervate the intrafusal muscle fibres.
See also:
- 11.2.2 POJA-L3294+3284+3286+3287+3285+3288+3289
Sensory receptors (neuromuscular spindles)
Keywords/Mesh: locomotor system, skeletal muscle, striated muscle, proprioceptor, muscle spindle, neuromuscular spindle, histology, POJA collection