Relation Between Testosterone Levels in Serum and Proteolytic Activity in the Neck Muscles of the Norwegian Reindeer ( Rangifer tarandus tarandus)

• Published in: Acta Zoologica
• Main Author: Lund‐Larsen, Tata Ringberg
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1977
• Subjects: Rangifer tarandus
• Online Access: http://dx.doi.org/10.1111/j.1463-6395.1977.tb00238.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1463-6395.1977.tb00238.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1463-6395.1977.tb00238.x

Abstract The characteristic hypertrophying of the male reindeer neck muscles during the rutting period, which coincides with the rise in serum testosterone levels, is found to be accompanied by a significant decrease in lysosomal proteolytic activity of the neck muscle cells. Conversely, during the period of neck muscle involution following the rapid decline in serum testosterone after the rut, a marked increase in neck muscle proteolytic activity is found. These changes in lysosomal activity do not parallel the changes in feed consumption and nutritional stage of the animals during the rutting period. The lysosomal proteolytic activity of the male reindeer neck muscles thus may be, at least partly, under the control of sex steroid hormones.