A factor from bursa of Fabricius inhibits in vitro the chorionic gonadotropin response of the XXXX testis.

@entity1573 @entity251 @entity3566
The effect of bursa of Fabricius on the endocrine function of the @entity1573 testis was studied using an isolated testis cell preparation. @entity251 secretion, both basal and under @entity3566 stimulation, was measured in the incubation medium. The bursal extract inhibited the response of the testis cells to @entity3566 detected as a reduced @entity251 secretion. The normal basal secretion of the testis cells was not modified by the bursal extract. To analyze some characteristics of the bursal factor, fractions of approximately known molecular weight were obtained by filtering through Amicon membranes. The active factor was found in the fraction corresponding to 1000-10000 Da. Its activity disappeared after heating of trypsin incubation, suggesting the peptidic nature of the bursal factor. Tissue extracts from gut and spleen did not modify the @entity3566 response of the testis cells. There was inhibition of the @entity3566 response by thymus extracts of the newly hatched @entity1573 . These results add new evidence of a modulatory effect of the immunogenic organs on the endocrine function of the testis in the newly hatched @entity1573 .
