Journal
ANATOMICAL RECORD PART A-DISCOVERIES IN MOLECULAR CELLULAR AND EVOLUTIONARY BIOLOGY
Volume 288A, Issue 10, Pages 1095-1104Publisher
WILEY-LISS
DOI: 10.1002/ar.a.20375
Keywords
fiber type; jaw muscle; temporalis; postnatal development; rabbit
Categories
Ask authors/readers for more resources
Postnatal changes in the fiber type composition and fiber cross-sectional area were investigated in the superficial (TEM1) and deep (TEM23) temporalis of male rabbits. It was hypothesized that, due to the transition from suckling to chewing during early postnatal development, the proportion of fast fiber types would decrease, while the proportion of fibers positive for myosin heavy chain (MyHC) cardiac alpha would increase, and that, due to the influence of testosterone during late postnatal development, the proportion of these a fibers would decrease again. Classification of the fibers types was performed by immunohistochemistry according to their MyHC content. The proportion of a fiber types significantly increased in both muscle portions from 2% and 8% for TEM1 and TEM23 at week 1 to 29% and 54% at week 8, respectively,. While in TEM1 the proportion of this fiber type did not change thereafter, it decreased again to 27% in TEM23 at week 20. The change for the fast fiber types was opposite to that of the a fiber types. Significantly more MyHC IIX fibers were found in TEM1 than in TEM23 in adult rabbits. In the first 8 weeks, the cross-sectional areas of all fibers increased. After this period, only MyHC cardiac alpha + I fibers continued to increase significantly. It was concluded that there are developmental differences in the myosin heavy chain transitions of the two portions of the temporalis muscle.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available