Influence of Rete Testis Fluid on the Metabolism of Testosterone by Cultured Principal Cells Isolated from the Proximal or Distal Caput of the Rat Epididymis

Abstract

Principle cells from 120 elutriations were used to improve procedures for culturing cells from the proximal or distal caput epididymidis. The criteria evaluated were metabolism of testosterone (T) to 5 alpha-reduced metabolites and cellular morphology after 6 days of culture. Isolated principal cells (greater than 90% viability) were cultured at 34 degrees C within a floating collagen matrix. Inclusion of transferrin or retinol in the culture medium increased the production of 5 alpha-reduced metabolites. Aggregation of principal cells before entrapment in the collagen matrix resulted in higher production of 5 alpha-reduced metabolites and more cells with a normal find structure than entrapment of dispersed cells in the matrix. Aggregated cells tended to form sheets or clusters, frequently arranged around a central lumen, with junctional complexes between adjacent cells. Cell polarity and morphologic features distinguishing principal cells from the proximal caput and distal caput epididymidis were retained. An average of 91% of the cells in aggregates were morphologically normal on Day 6 of culture in contrast to 5% for the single cells. Utilizing the improved culture procedure, we tested the hypothesis that ovine rete testis fluid (RTF) contains macromolecules which would aid in maintenance of a high rate of T metabolism. Principal cells were cultured in medium supplemented with 0 or 10% RTF, 10% ultrafiltrate of RTF (less than 10,000 daltons), or 10% newborn calf serum (NCS). Conversion of [3H]T to 5 alpha-reduced metabolites by cells from the proximal caput was twice that in cells from the distal caput on Day 6 of culture. Inclusion in the culture medium of 10% RTF or 10% NCS, but not 10% ultrafiltrate of RTF, increased (P less than 0.05) the production of 5 alpha-reduced metabolites by cells from both regions. We conclude that macromolecules in RTF or NCS are beneficial to maintenance of the ability to metabolize T by cultured principal cells, especially those from the proximal caput.

Achievement of spermatogenesis and genital tract maturation in hypogonadotropic hypogonadic subjects during long term treatment with gonadotropins or LHRH

“…The intraluminal androgen contribution from rete testis to the epididymis is greater than that supplied by the systemic circulation, and dihydrotestosterone, which is the most important androgen in epididymal metabo-lism, is produced by the epididymis itself (Robaire & Zirkin, 1981;Brown et al, 1983). The intraluminal androgen contribution from rete testis to the epididymis is greater than that supplied by the systemic circulation, and dihydrotestosterone, which is the most important androgen in epididymal metabo-lism, is produced by the epididymis itself (Robaire & Zirkin, 1981;Brown et al, 1983).…”

“…Therefore, we believe that they are not sufficient to normalize epididymal function. The intraluminal androgen contribution from rete testis to the epididymis is greater than that supplied by the systemic circulation, and dihydrotestosterone, which is the most important androgen in epididymal metabo-lism, is produced by the epididymis itself (Robaire & Zirkin, 1981;Brown et al, 1983). In monolateral cryptorchidism, in addition to the prevalent alteration of spermatogenesis, there are also decreases in homolateral epididymal weight and carnitine production (Brooks et al, 1974).…”

Sperm-associated antigen 11A is expressed exclusively in the principal cells of the mouse caput epididymis in an androgen-dependent manner

“…This notion is based on previous studies that orchidectomy and efferent duct ligation induces apoptotic cell death in the caput epididymis that reach maximum at day 3 [44,45]. Several epididymal genes are regulated by testicular factors, including gamma-glutamyltransferase 1 ( Ggt1 , regulated by fibroblast growth factor (FGF)) [46], 5-alpha reductase (regulated by androgen binding protein (ABP)) [47] and proenkephalin ( Penk , regulated by sperm-associated factors) [19]. The primary regulation of caput-specific Spag11a by androgen confirmed our previous report that epididymal genes enriched in the initial segment are more dependent on testicular factors whereas androgen regulates most of the caput-enriched genes [20].…”

Enzymohistochemical and immunohistochemical study of the human efferent ducts

“…Present results agree with biochemical studies which have reported oestrogen receptors in the epididymis of the rabbit (Danzo & Eller, 1979), monkey (Kamal et al, 1985), ram (Tekpetey & Amann, 1988) and man (Murphy et al, 1980), and reveal that these receptors are abundant in the epithelium and muscular coat of the human efferent ducts. Although the role of oestrogens in the epididymis is not yet understood, it has been suggested that they act by blocking androgen uptake or interfering with androgen metabolism (Brown et al, 1983). A direct effect of oestrogens on the epididymis has also been reported involving stimulation of the synthesis of several epididymal proteins (Toney & Danzo, 1990).…”