Bidder's organ in the male toad Bufo arenarum.

SCAIA MARIA FLORENCIA; REGUEIRA ELEONORA; CEBALLOS NORA RAQUEL

Ravenna, Italia.

Congreso; 25th European Society for Comparative Physiology and Biochemistry; 2008

ESCPB

The Bidder organ (BO) is a rudimentary ovary located at the anterior end of the testis in male true toads (Bufonidae). The presence of this organ in bufonids provides an exceptional condition for the study of the effect of environmental pollutants on the development of BO. It has been suggested that the inhibition of oogenesis in BO is due to the presence of a functional testis. The main goal of this work is to analyze the correlation between glucocorticoids, androgens and the development of BO. In addition, the influence of the area of capture as well as the season of the year was also studied. As well, steroidogenesis in BO was analyzed. BO expresses aromatase and 3beta-hydroxysteroid dehydrogenase activities measured by the conversion of substrates into products. Moreover, the presence of cytochrome P450 side-chain cleavage enzyme was also determined by immunocytochemistry. These results indicate that this organ has the capacity of synthesize estrogens from cholesterol. Specific activity of aromatase, expressed as nmole per mg protein, increased with organ development. Destruction of Leydig cells with ethane 1,2- dimethane sulphonate did not modified the activity of neither steroidogenic enzymes nor the oogenesis, suggesting that both processes are independent of testicular steroidogenesis. In addition, the presence and weight of BO did not correlate with reproductive status neither with glucocorticoids. However, the degree of pollution of the area of capture seemed to have a great influence on those parameters, suggesting that cues associated with the environment but not with sexual maturity influence BO volume.