The epididymides of animals treated with GnRHa and DES showed retarded development, as evidenced by smaller epididymal lumens when compared with control rats or those treated with DES + TE (Fig. 4, A and D, respectively). Coadministration of DES + TE resulted in the maintenance of epididymal epithelial H+-ATPase immunoexpression at levels similar to controls. Morphologically, the epididymal epithelium of the animals treated with DES + TE appeared broadly similar to that in controls. However, despite the maintenance of H+-ATPase levels, the testes weight of these animals were similar to those measured in rats treated with DES alone or with GnRHa (Table 1).
The number of H+-ATPase-positive cells per millimeter of basal membrane was quantified in each group (Fig. 5). Rats treated neonatally with either GnRHa or DES exhibited —65% fewer H+-ATPase positive cells, whereas treatment with EE caused a reduction of 45% (Fig. 5). Animals coadministered DES + TE neonatally had H+-ATPase positive cells that were comparable in number to the control cohort at Day 25 (50.3 ± 13.8 vs. 49.6 ± 9.8 immunopositive cells per millimeter of epididymal basal membrane, respectively).
FIG. 5. Quantification of the number of H+-ATPase-positive cells per millimeter of epididymal tubule basal membrane at Day 25 in control rats and in rats treated neonatally with either GnRHa, DES, EE, or DES + TE. **P < 0.01, ***P < 0.001 compared with control. Data are means ± SEM for n = 4-8 (as stated in Table 1).
TABLE 1. Testis weight and number of rats per cohort in study 2 at age 25 days in vehicle-treated (control) rats and in animals treated neonatally with GnRHa, DES, EE, DES + TE, or in a separate experiment, flutamide.
|Treatment||n||Testis weight (mg) ± SD|
|Control 1||6||243.9 ± 15.0|
|GnRHa||6||31.6 ± 8.6***|
|DES 10 pg||4||43.2 ± 11.3***|
|EE 10 pg||8||60.0 ± 14.2***|
|DES + TE||5||36.1 ± 3.7***|
|Control 2||3||181.6 ± 41.5|
|Flutamide||3||192.0 ± 0.02|
*** P < 0.001 compared with the Control 1 group.