| dc.description.abstract | Effects of ethane dimethanesulphonate (EDS), a diester of suIphonic acid, on
testicular and epididymal morphology and plasma testosterone profiles were studied
using both light and electron microscopic techniques and radioimmunoassay (RIA). In
order to determine stage specific changes in the seminiferous tubules, the seminiferous
cycle, hitherto undescribed in goats, was described using light microscopy. Based on
various cell associations and the accompanying changes in spermatid shape and location,
eight (8) stages of the cycle with six (6) main divisions were identified. These stages
appeared in the cycle with the following frequency; 34% (stage 1), 13% (stage 2), 12%
(stage 3), 9% (stage4), 27% (stage5-7) and 5% (stage 8). When EDS was administered at
a higher dose (75mg/kg) death of three members of the group (G 1) followed 24hrs later
due to toxicity but the lower dose (2Smg/kg) was satisfactorily tolerated. In both cases,
there was no noticeable effect of the compound on the Leydig cell structure six (6) days
post-treatment. However, there was marked disruption of spermatogenesis characterized
by spermatogonial degeneration, chromatin condensation in leptotene spermatocytes,
failure of chromatin re-organization in stage 4 tubules, perip?eral re-distribution of
chromatin in developing spermatids of stages 1, 2 and 5 and retention of maturation
phase spermatids of stage 2 tubules. Sertoli cells showed accumulation of
intracytoplasmic vesicles and intercellular vacuoles occurred within the epithelium.
In the epididymis, there was region-specific involution of the epithelium. In the
caput region, there was increased cytoplasmic density accompanied by enlarged vacuoles
and paucity of secretory vesicles in the apical cytoplasm. The Golgi cisternae were
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dilated and disorganized and, in the basal aspect, large dense staining bodieslinclusions,
degenerative mitochondria and lamellated bodies were observed. In the corpus, large
vacuoles containing flocculent materials occurred in the entire cell cytoplasm but were
particularly numerous and large in mid cytoplasm. There was a dramatic reduction in
epithelial height in the cauda epididymis accompanied by sparse distribution of markedly
shortened microvilli. The epithelial cells had extensively lobulated nuclei and
disorganized cytoplasm with dilated Golgi apparatus and large conglomerations of
tubular structures.
Diurnal (circadian) and two-hour testosterone measurements at both dose levels
(75mg/kg and 25mg/kg), irrespective of the duration of treatment, revealed no significant
effect of the compound on testosterone production (P>0.05). The pre-treatment diurnal
concentration was 0.82 ± 0.22 - 4.45 ± 1.79 nmoIlL and 0.45 ± 0.10 - 1.84 ± 1.11
nmol/L (n=8) for the morning and evening respectively. The morning values were
significantly higher than the evening ones (P<0.05). One week post-treatment with the
higher dose, the concentration was 0.31 ± 0.31- 4.02 ± 3.18 nmol/L and 0.30 ± 0.10 - 1.7
± 0.50 nmol/L (n=2) while that of the lower dose was 1.03 ± 0.09 - 6.52 ± 3.08 nmol/L
and 0.59 ± 0.06 - 2.13 ± 1.34 nmol/L (n=3) for both morning and evening respectively.
Three weeks post-treatment, testosterone concentrations were 0.22 ± 0.22 - 0.59 ± 0 19
nmol/L and 0.27 ± 0.11 - 0.86 ± 0.5 nmol/L (n=2) (higher dose) and 1.16 ± 0.64 -4.43 ±
2.0 nmol/L and 0.52 ± 0.05 -1.7l. ± 0.96 nmol/L (n=3) (lower dose) for both morning and
evening. The pre-treatment two-hour measurements were 0.81 ± 0.35 nmol/L -2.0 ± 1.27
nmol/L (n=l 0). Two weeks post-treatment, the levels were 1.13 ± 0.63 - 3.61 ± 3.19
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(n=2) and 0.86 ± 0.38 nmolfL - 3.00 ± 2.72 nmol/L (n=3) for both the higher and lower
doses respectively.
Taken together, these results suggest that in goats, EDS has no effect on Leydig
cell function hence, no significant influence on testosterone levels but it has a direct
effect on the seminiferous as well as epididymal epithelium. | en |
