Endocrinology, Vol 100, 835-838, Copyright © 1977 by Endocrine Society
Effect of testosterone propionate on levels of carnitine and testicular androgen binding protein (ABP) in rat epididymis
T Bohmer, SC Weddington and V Hansson
Institute of Pathology and Surgical Research, University Hospital, Oslo, Norway.
Twenty-one day old rats were treated for 10 days with various doses of
testosterone propionate (TP) (10 micrograms to 10 mg/day) and the levels of
L-carnitine and testicular androgen binding protein (ABP) were measured in
the 105,000 x g supernatant fractions of epididymis. Treatment with TP in
increasing doses had a biphasic effect on the level of ABP in the
epididymis; thus, with doses of TP of 10-100 micrograms/day, the ABP level
was reduced in a dose-dependent way, whereas with higher doses of TP (0.2
to 1 mg/day) the extent of reduction of ABP levels was less as the dose of
TP increased. Treatment with high doses (5 mg or 10 mg/day) did not change
the ABP level compared with non-treated control rats. The concentration of
carnitine increased linearly (log dose-response) with increasing doses of
TP (10- 200 micrograms/day) and there was no further increase after
treatment with higher doses of TP. In adult rats TP (175 micrograms and
17.5 mg/day) reduced the level of ABP but not the level of carnitine in the
epididymis. These studies suggest, therefore, that ABP is of minor
importance for the supply of androgens to the carnitine-concentrating cells
in the corpus and cauda epididymis.
