Testicular androgen binding protein (ABP) - a parameter of Sertoli cell secretory function.

Using ABP as an index of Sertoli cell secretory function, several important features of the Sertoli cell have emerged: 1. The stimulation of ABP production by FSH clearly points to the Sertoli cell as a target cell for FSH (3,4,9-16,21,24). 2. The dramatic effects of androgens on ABP production both in immature and mature rats also suggest that the Sertoli cell is a target cell for androgen (3,12,14,16,25). 3. The striking reduction in ABP production in the cryptorchid testis raises the question whether impairment of Sertoli cell function is the primary reason for the loss of germ cells that occurs in this condition (20). 4. Drugs like nitrofurazone or ethionine, or X-irradiation only slightly affect the secretory function of the Sertoli cells (ABP production), indicating that these treatments most probably have direct effects on the germ cells as well. Thus, measurement of ABP production rate is a very important tool in order to evaluate how hormones, drugs and physical injuries might affect the secretory function of the Sertoli cell. This test system might be of great use in order to study the physiology and hormonal regulation of the Sertoli cells. It might also be valuable in pharmacological and toxicological studies.