title: The effects of orchidectomy and the role of testosterone in determining the growth of male mice selected for increased body weight.
abstract: Male mice selected for increased body weight and unselected controls were compared with intact littermates at 10 weeks of age following bilateral orchidectomy at 21 days post partum. Castrated mice were lighter in both lines and orchidectomy abolished approximately half the increase in body weight brought about by selection. The lungs were unaffected but there were decreases in the weights of the heart, liver and kidney and of the biceps brachii and tibialis anterior muscles in both lines. The decreases in body weight, organ weight and muscle weight, both absolute and relative, were greater in high growth than in unselected mice. Orchidectomy affected the size but not the number of cells in the liver and kidney. These results support the hypothesis that the increased level of circulating testosterone reported previously in male mice selected for increased body weight is responsible for that proportion of their greater body weight which is attributable to increased cell size.
mesh_terms: D000818:Animals; D001835:Body Weight; D002452:Cell Count; D007668:Kidney / Q000166:cytology / Q000254:growth & development; D008099:Liver / Q000166:cytology / Q000254:growth & development; D008297:Male; D051379:Mice / Q000254:growth & development*; D009919:Orchiectomy; D009929:Organ Size; D013739:Testosterone / Q000502:physiology*
chemical_list: D013739:Testosterone