当前位置： SCI文献检索 > JOURNAL OF MORPHOLOGY期刊下所有文献 > Neuromuscular organization of feline anterior sartorius: II. Intramuscular length changes and complex length-tension relationships during stimulation of individual nerve branches.

Neuromuscular organization of feline anterior sartorius: II. Intramuscular length changes and complex length-tension relationships during stimulation of individual nerve branches.

Abstract：

:The feline anterior sartorius is a long strap-like muscle composed of short muscle fibers. Nerve branches that enter this muscle contain the axons of motor units whose constituent muscle fibers are distributed asymmetrically within the muscle. In the present study, twitch and tetanic isometric contractions were evoked by stimulating individual nerve branches while muscle force was recorded and intramuscular length changes were monitored optically by the movement of reflective markers on the muscle. Contractions elicited by stimulating the parent nerve produced little change in the positions of the surface markers. Contractions elicited by stimulating the proximally or distally directed nerve branches caused the muscle to shorten at the end closest to the nerve branch and lengthen at the opposite end. Some muscles were supplied by a centrally directed nerve branch whose stimulation produced variable effects: in some cases a portion of the muscle shortened whereas the rest lengthened, but in other cases, the positions of the surface markers showed little change. The intramuscular length changes produced by stimulating single nerve branches were greater during isometric contractions at short whole-muscle lengths than at long whole-muscle lengths. The twitch and tetanic length-tension relationships obtained by stimulating the individual nerve branches were not congruent with the length-tension relationship produced when the parent nerve was stimulated. At short whole-muscle lengths, stimulation of a single nerve branch generated only a small fraction of the force that could be generated by the muscle when the parent nerve was stimulated. As whole-muscle length increased, an increased fraction of total muscle force could be generated by stimulating a single nerve branch. The results suggest that a complex relationship between passive and active elements contributes to the total muscle force and depends on the distribution of active and passive muscle units throughout the muscle.

journal_name

J Morphol

journal_title

Journal of morphology

authors

Scott SH,Thomson DB,Richmond FJ,Loeb GE

doi

10.1002/jmor.1052130204

keywords:

subject

Has Abstract

pub_date

1992-08-01 00:00:00

pages

171-83

issue

eissn

0362-2525

issn

1097-4687

journal_volume

213

pub_type

杂志文章

在线工具

Neuromuscular organization of feline anterior sartorius: II. Intramuscular length changes and complex length-tension relationships during stimulation of individual nerve branches.