E. M. Ritzén

BLOOD-TESTIS BARRIER: Maintained Function of Inter-Sertoli Cell Junctions in Experimental Cryptorchidism in the Rat, as Judged by a Simple Lanthanum-Immersion Technique

In order to elucidate the mechanisms behind the deleterious effects on the germinal epithelium of experimental cryptorchidism the hypothesis that a leaking blood‐testis barrier is the cause of the damage was tested. The permeability of the specialized inter‐ Sertoli cell junctions to lanthanum after experimental cryptorchidism for 0.5 to 12 days was studied in the rat. In none of the time periods studied lanthanum had penetrated beyond the inter‐Sertoli cell junctions. A simple lanthanum immersion technique was used. Testes of 15‐days old rats (before the development of the barrier) were used as a positive control of the method, and in these testes lanthanum had penetrated up to the future lumen.

Concentration of Steroid Hormones and Androgen Binding Protein (ABP) in Rabbit Efferent Duct Fluid

Androgenic hormones are necessary for the completion of normal spermatogenesis (1) and may mediate the stimulatory influence of the gonadotrophins FSH and LH on germ cell development (2). Although the stimulatory effects of LH on Leydig cell secretion are well documented, the mechanism by which FSH influences the various testicular compartments has been more speculative. The demonstration of a high affinity androgen binding protein (ABP) in the testicular efferent duct fluid (EDF) of the rat (3,4) and rabbit (5) and its control by FSH (2,6,7) has raised the possibility that FSH may influence the local concentration of androgens in the immediate vicinity of the developing and maturing germ cells. In order to test this hypothesis, a radioimmunoassay technique, which enables the simultaneous measurement of 8 steroids, including the major androgens, (8,9) was applied to a study of the steroid concentrations in rabbit EDF. It was hoped that steroid assays in conjunction with ABP measurements in the same samples would answer the following questions: (a) What is the steroid composition of the fluid bathing the testicular sperm? (b) Is there a relationship between the concentration of androgens and the levels of ABP?