Comparison of the Effect of Castration on the Development of Postural and Non-Postural Muscles of Mice

Abstract

The effect of castration on the development of muscle mass of postural and non-postural muscles was studied in 18 male mice (9 castrated, 9 uncastrated). Results obtained indicated that the castrated males grew faster and were bigger in body size and weight at maturity than the intact males. The bigger body size of castrated males was not due to larger muscle mass but was probably due to increased subcutaneous fat deposition. Atrophy of muscles usually observed following castration was significantly greater in the non-postural (biceps brachii) muscle of the forelimb as compared to the postural (triceps brachii) muscle of the forelimb. Conversely, the amount of reduction in muscle mass was similar in both postural (soleus) and non-postural (tibialis cranialis) muscles of the hindlimb.

Role of androgens in energy metabolism affecting on body composition, metabolic syndrome, type 2 diabetes, cardiovascular disease, and longevity: lessons from a meta-analysis and rodent studies

“…Muscle satellite cell-specific AR-KO also did not affect the inferior muscle mass [155]. Castration-dependent muscle loss is more prominent in non-postural muscles than in the postural muscle of the forelimb, whereas similar reductions in muscle mass are observed in both the postural and non-postural muscles of the hindlimb [133]. On the other hand, castrated and global AR-KO mice show decreases in relative lean mass in a HFD-dependent manner [128].…”

“…This obese phenotype is observed in multiple laboratories, but not in every laboratory [124][125][126][127][128][129][130][131][132]. In castration models, the obese phenotype is observed when mice are castrated before [133] or after [111] maturation, although controversy remains [120][121][122]128,[134][135][136][137]. These results suggest that while androgen ablation by AR-KO or castration can cause obesity in laboratory animals, androgen ablation alone may be insufficient for the development of obesity.…”

Effects of Maternal Alcohol Consumption on the Allometric Growth of Muscles in Fetal and Neonatal Rats

“…The differences observed may be related to the amount of load placed on muscles of forelimb and hindlimb. The greater part of the body weight in a standing animal is usually borne by the forelimb [Ihemelandu and Ibebunjo, 1992], hence the postural muscles (triceps brachii) in the forelimbs may be performing more work than the biceps brachii in opposition to gravitational force. This may have led to the triceps brachii muscle of the prenatal alcohol-exposed group growing faster than the biceps brachii at 11 and 14 weeks of age.…”