All Phenotypes Nr0b2<tm1.1Auw> MGI Mouse

small testis ( J:118368 )

• at 12 weeks of age

decreased testis weight ( J:118368 )

• at 30 days of age testicular weight is already decreased compared to wild-type mice

• at 12 weeks of age, average testis weight is 0.59 +/- 0.02 compared to 0.74 +/- 0.02 in controls

abnormal testis physiology ( J:118368 )

• elevated intratesticular levels of all-trans-retinoic acid at 9 days of age

• however, no change in liver levels of all-trans-retinoic acid is detected

• functionally significant elevated intratesticular concentrations of testosterone compared to controls at but not before 30 days of age

increased epididymis weight ( J:118368 )

• at 30 days of age epididymal weight is already increased compared to wild-type mice

• weight is 17% higher than in controls at 12 weeks of age

early sexual maturation ( J:118368 )

• at 11 - 20 days of age, expression of meiotic specific cyclins is increased and expression of mitotic specific cyclins is decreased relative to controls

• at 28 days of age 13% of seminiferous tubules contain elongated spermatids compared to just 1% of control tubules

• all seminiferous tubules contain elongated spermatids by 44 days of age compared to 56 days of age in controls

• males are able to successfully impregnate females 8 days earlier than controls

• plasma concentrations of testosterone begin to increase earlier during prepubertal development than in controls

increased circulating testosterone level ( J:118368 )

• elevated plasma and intratesticular concentrations of testosterone compared to controls at but not before 30 days of age

• however, plasma levels of luteinizing hormone are similar to controls suggesting increased testosterone levels are due to a local rather than central abnormality in testosterone synthesis