the development, growth, differentiation and function of the prostatic gland are considcered to be controlled primarily by androgen. Several hypothesis that the growth factors could mediated the effect of androgen in the prostatic cells and the
development of the benign prostatic hyperplasia and malignant prostatic growth may be caused by inappropriate expression of these factors are postulated. In order to define the relationship between androgen and growth factors, we evaluated the
changes
of the levels of epidermal growth factor (EGF) and basic fibroblastgrowth factor (basic FGF) in prostatic regression and regrowth induced by androgen modulation in rat. Male inbred Spragus Dawley rats measuring approximately 250gm in weight were
used.
Prostatic regression was induced by castration and regrowth induced by androgen replacement. The level of EGF and basic FGF were measured by ELISA method in homogenized rat ventral prostate. It was serially determined that the weight of the
ventral
prostate and the level of EGF and basic FGF on the 1, 3, 5, 7 and 14th day after castration and androgen replacement.
The prostatic weight was measured about 350mg in normal controls and decreased about 50mg on 7 th day after castration and there was no change thereafter. After androgen replacement, the prostatic weight increased and reached about 500mg which
was
larger than normal control on 14 th day. Normal rat ventral prostate was composed of tubuloalveolar glands lined by two layer of columnar or cuboidal cells and the small amount of stromal tissue. On 7 th day after castration, the epithelial cells
were
atrophied and slughed. After androgen replacement.
the prostatic glands were regrown and restoration of normal glandular structure was noted. On 14 th day after androgen replacement, overgrowth of glands and intraluminal proliferation of epithelial cells. The level of EGF changed similarly with
the
change fo prostatic weight. It decreased to undetectable level on 5 th day after castration and increased gradually after androgen replacement. The decrease and increase of EGF level preceeed the change of prostatic weight. Also, the level of
basic
FGF
changed similarly with the level of EGF and change of prostatic weight.
In conclusion, the levels of EGF, basic FGF and prostatic weight were varied according to androgen depletion or replacement. The decrease and increase of EGF and basic FGF level preeeeded the change of prostatic weith. These results suggest that
EGF and
basic FGF influence the prostatic growth by androgen dependent pathway.
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