Comparison of the growth-promoting effects of testosterone and 7-alpha-methyl-19-nor-testosterone (MENT) on the prostate and levator ani muscle of LPB-tag transgenic mice.
BACKGROUND
7-alpha-methyl-19-nortestosterone (MENT) is being considered for androgen replacement in testosterone deficient men and as a male contraceptive. Because androgenic effects on the prostate are a major concern, we have evaluated MENT in a transgenic model of prostate cancer.


METHODS
LPB-Tag mice were castrated and infused with testosterone (T; 5 or 30 microg/day) or MENT (5 or 30 microg/day) for 4 weeks. Prostate, seminal vesicle, and levator ani muscle (LAM) weights were compared.


RESULTS
At an equivalent dose, MENT maintained or stimulated the mean weights of these organs more than T. However, the dorsolateral prostate/LAM ratio of weights did not favor MENT, but DNA/mg tissue and Ki 67 immunostaining suggested that MENT may increase DNA less than T.


CONCLUSIONS
MENT is more potent than T in maintaining or stimulating prostate, seminal vesicle, and LAM. Using doses that resulted in comparable stimulation of the levator ani muscle, MENT had similar effect on prostate weight, but increased DNA/mg prostate less than T in this transgenic mouse model of prostate cancer.
Shao
T C
TC
Department of Medicine, Michael E. DeBakey VA Medical Center and Baylor College of Medicine, Houston 77030, Texas, USA. tshao@bcm.tmc.edu
Li
H L
HL
Kasper
S
S
Matusik
R
R
Ittmann
M
M
Cunningham
G R
GR
D000818:Animals; D003272:Contraceptive Agents, Male / Q000494:pharmacology; D004247:DNA / Q000096:biosynthesis; D004963:Estrenes / Q000494:pharmacology*; D005260:Female; D020249:Hormone Replacement Therapy; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D018482:Muscle, Skeletal / Q000187:drug effects / Q000254:growth & development; D011471:Prostatic Neoplasms / Q000473:pathology*; D013737:Testis / Q000187:drug effects* / Q000254:growth & development; D013739:Testosterone / Q000172:deficiency / Q000502:physiology*
D003272:Contraceptive Agents, Male; D004963:Estrenes; D013739:Testosterone; C073330:methylestrenolone; D004247:DNA