Recruitment Patterns of Intrafusal and Extrafusal Fibres in Mice During Prolonged Swimming
Though recruitment patterns of fast and slow extrafusal fibres in exercise are well established (Armstrong, Saubert, Sembrovich, Shepherd & Gollnick, 1974), there have been no reports to date regarding the recruitment of different intrafusal fibres of mammalian muscle spindles during voluntary movement. We have used glycogen depletion during prolonged swimming to investigate recruitment patterns of the three intrafusal fibre types in mice. The degree of glycogen depletion was estimated by two methods, visual inspection (VI) and our newly developed optical scanning (OS) of periodic acid Schiff (PAS)-stained sections. Fibre typing was done by combining morphological, histochemical, and immunohistochemical characteristics, and we compared the results for intrafusal and extrafusal fibres.
KeywordsRecruitment Pattern Glycogen Depletion Glycogen Concentration Intrafusal Fibre Nuclear Chain
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