Biology of Reproduction, Vol 21, 991-997, Copyright © 1979 by Society for the Study of Reproduction

Development of the LH-Response in Fetal Guinea Pig Testes

¹ Laboratory for Cell Biology and Histology, Medical Faculty, University of Leiden and Department of Endocrinology, Growth and Reproduction Erasmus University, Rotterdam, The Netherlands

The influence of LH on testosterone secretion by testes from 25-30-day-old guinea pig fetuses cultured in vitro was investigated. Testosterone secretion by testes from 30-day-old fetuses could be stimulated by LH during the first 24 h in organ culture. Testosterone secretion by testes from 25-29-day-old fetuses could not be stimulated by LH during 5 days in organ culture. Development of testosterone and androstenedione synthesis by testes from fetuses of 25 days was observed during 5 days in organ culture. A stimulation of testosterone and androstenedione production by LH at that fetal age, however, could not be measured. Testosterone synthesis by fetal guinea pig testes explanted at 25 days could be stimulated by LH when they were precultured for 6 days. Similarly [¹²⁵I]-hCG binding by gonads from fetuses of 25 days could be detected only after organ culture of these gonads for at least 6 days. These results indicate that in early guinea pig fetuses development of testosterone synthesis precedes the development of LH responsiveness.

Note:
ACKNOWLEDGMENTS The authors are grateful to Miss M.J.A. van Driel and Mrs. L. M. Knippenberg-Lindh, Department of Biochemistry II, Erasmus University, Rotterdam, for measurement of the biological activity of the [¹²⁵I]-hCG. The expert technical assistance of Mrs. A.N.F. Feenstra-de Lijster is gratefully acknowledged. This work was supported in part by the Dutch Foundation for Medical Research (FUNGO).