Francisco Martínez-García

The apical mitochondria-rich cells of the mammalian epididymis.

Summary The morphology and function of the apical mitochondria‐rich cells in the mammalian ductus epididymidis epithelium are revised. These cells are similar in all mammalian species studied. Apical mitochondria‐rich cells are scarce (1–5 cells/100 principal cells) and are mainly found in the initial epididymal segments. Their morphology varies from slender cells that extend from the basal lamina to the epididymal lumen, to round cells that protrude into the lumen and are not in contact with the basal lamina. Their cytoplasm is more electron‐dense than that of principal cells and contains more mitochondria which, in some species, are surrounded by rough endoplasmic reticulum cisternae. The adluminal cytoplasm displays a few short microvilli and contains many acid phosphatase positive vesicles. Apical mitochondria‐rich cells differ from the principal cells in some histochemical features such as: (a) different lectin‐staining pattern; (b) more intense reaction to the enzymatic activities: carbonic anhydrase, Ca2+‐ATPase, peanut‐agglutinin‐sialidase, NADP dehydrogenase, succinate dehydrogenase, α‐galactosidase and β‐galactosidase; (c) more intense immunoreaction to several cytokeratin types and to estradiol‐related receptor protein; (d) weaker immunoreaction to epithelial membrane antigen and to retinol‐binding protein. Although the function of the apical mitochondria‐rich cells is still unknown, the following possible functions have been suggested: holocrine secretion; cooperation with the principal cells in epididymal reabsorption of testicular fluid; and acidification of epididymal fluid. Experimental results suggest that differentiation and maintenance of apical mitochondria‐rich cells are not under androgen control and that these cells are sensitive to estrogen stimulation.

Androgen Insensitivity Syndrome An Immunohistochemical, Ultrastructural, and Morphometric Study

OBJECTIVE To evaluate the morphometric, immunohistochemical, and ultrastructural lesions of the testes in prepubertal and adult patients with androgen insensitivity syndrome. METHODS We examined the testicular biopsy using immunohistochemistry for vimentin, smooth muscle actin, and collagen IV antigens. Quantification of seminiferous tubules and testicular interstitium was performed in prepubertal and adult patients with androgen insensitivity syndrome and results were compared with normal testes from both infants and adults. RESULTS The adult testes presented nodular and diffuse lesions that consisted of Sertoli-cell-only seminiferous tubules. Two types of Sertoli cells could be distinguished, namely, immature vimentin-positive Sertoli cells and nearly mature Sertoli cells. In the nodules, the lamina propria was thin and contained a scant number of actin-positive peritubular cells. Leydig cells were hyperplastic. The prepubertal patients showed only diffuse lesions characterized by Sertoli cell hyperplasia, decreased germ cell numbers, and a discontinuous immunoreaction to collagen IV. CONCLUSIONS The testicular lesions in androgen insensitivity syndrome are probably caused by primary alterations that begin during gestation. These lesions become progressively more pronounced at puberty, when the nodular lesion pattern (adenomas) is completely developed.

Testosterone immunoexpression in human Leydig cells of the tunica albuginea testis and spermatic cord. A quantitative study in normal foetuses, young adults, elderly men and patients with cryptorchidism.

Summary. A semi‐quantitative study of the extraparenchymal Leydig cells in the tunica albuginea testis and spermatic cord was performed on histological sections immunostained with anti‐testosterone antibodies in the testes and spermatic cords obtained from human foetuses, adults and elderly men without testicular or related diseases (autopsy specimens), as well as from adult men with cryptorchidism (surgical specimens). The albugineal Leydig cells appeared in small groups in the vicinity of blood vessels. The Leydig cells of the spermatic cord usually appeared inside or around nerve trunks. The percentages of testes and spermatic cords with extraparenchymal Ley‐dig cells were higher in the cryptorchid testis group than in the normal male groups. The number of Leydig cells per mm2 in the tunica albuginea testis was higher in normal adult males than in foetuses. This number decreased in elderly men and increased markedly in cryptorchidism. The number of Leydig cells per mm2 in the spermatic cord was also higher in normal adults than in foetuses and it did not change with either advancing age or cryptorchidism. In foetuses, the percentage of cells intensely immunostained by antitestosterone antibodies in the tunica albuginea and spermatic cord did not differ significantly from that found in the testicular parenchyma, whereas in the other three groups (adult, elderly, and cryptorchid men) the percentages of these cells in the tunica albuginea and spermatic cord were significantly lower than in the testicular parenchyma.

The Effect of Parathion on Mouse Testicular and Epididymal Development Cultured in Chicken Allantochorion

Parathion is a widely used organophosphoric pesticide which has also been reported to interfere with mouse spermatogenesis. Moreover it has been related to prenatal toxicity in mammals. Sixteen A/ Snell mice were sacrificed at day 17 of pregnancy. Testes and epididymides of the male fetuses were implanted in the allantochorion of chicken eggs. Three experimental conditions of the egg injections were considered: Group I: 1 ml of parathion (0.5 mg/ml), Group II: 1 ml of parathion (1 mg/ml), and Group III: 1 ml distilled water (control group). The implanted subjects continued their development for 4 days (i.e. to complete the gestational period for mice). The cell proliferation and differentiation of the epithelial cells of the epididymis were evaluated with the use of the monoclonal antiproliferating cell nuclear antigen (PCNA-cyclin) antibody, and the AE1 keratin complex antibody. Parathion altered the allantochorion, as 15% of the chicken embryos died in Group I and 40% in Group II, vs. only 8% in controls (Group III). However, no malformations were seen in the surviving embryos. In the testicular implants, the seminiferous cords of Group I had the same cytological characteristics of germ and pre-Sertoli cells as the control, except for involuting Leydig cells. Contrarily, in the cases with higher doses of parathion (Group II), there was a complete disorganisation of the seminiferous cords and the interstitium. In some testes, hyaline degeneration of the seminiferous cords was observed. No cell proliferation was evident, and the epididymal morphology was apparently unaffected. Therefore, parathion seems to interfere with normal testicular differentiation. However, in spite of interstitial damage, the epididymal development seems unaltered. Since the epididymis is an androgen-dependent organ, it may be postulated that testosterone production is still sufficient to support epididymal development but not spermatogenic cell line differentiation.

Macro-orchidism: Light and electron microscopic study of four cases

A hormonal and quantitative light microscopy study of one man with macro-orchidism associated with mental retardation and fragile X chromosome (case no. 1) and three men with idiopathic macro-orchidism (cases no. 2 to 4) is reported. Hormonal study revealed slightly increased follicle-stimulating hormone serum levels in cases no. 1 to 3. The testes from cases no. 1 (orchidoepididymoectomy specimen) and 2 (testicular biopsy) presented interstitial edema and three different tubular patterns that were arranged in a mosaic-like manner. Type I tubules had an increased diameter (less than 220 microns), dilated lumen, and thin seminiferous epithelium usually consisting of Sertoli cells, spermatogonia, primary spermatocytes, and sometimes a few spermatids. Type II tubules had a normal diameter (180 to 220 microns) and germ cell development varied between complete spermatogenesis and Sertoli-cell-only tubules. Type III tubules had decreased diameter (less than 180 microns), atrophic seminiferous epithelium, and thickened tunica propria. The appearance of the nuclei of the Sertoli cells in the three types of tubules could be either mature or immature. Some of the mature Sertoli cells presented a granular cytoplasm. A few of these granular cells grouped together, forming nests that protruded into the tubular lumen. The testicular biopsies from cases no. 3 and 4 only presented type II tubules that contained both mature and immature Sertoli cells. Quantitative study revealed that the large testicular size was principally due to an increased tubular length in all four cases. Although the seminiferous tubule lesions and interstitial edema suggest an obstructive process, the testicular excretory ducts (studied in case no. 1) appeared normal or only slightly dilated. It is possible that the seminiferous tubule lesions (dilated lumen and germ cell depletion) might be secondary to the Sertoli cell lesions (granular cytoplasm and nuclear immature-like pattern.

KERATINAS: BIOLOGIA CELULAR Y SIGNIFICADO FUNCIONAL NORMAL Y PATOLOGICO

Keratins are intermediate filaments of the cytoskeleton of epithelial cells. They express themselves in simple (Ks. 7, 8, 18, 19 y 20) or stratitified epithelia (Ks. 1, 2, 5, 9, 10, 11, 16). The different expression of these multigenic cytoskeletal proteins is related to cell specific differentiation programs (OSBORN & WEBER, 1983; NAGLE, 1988); For these reasons the analysis of keratins are very relevant for the study of new aspects of histology, histopathology and developmental biology. Moreover, evaluation of keratins by immunofluorescent or immunohistochemistry is useful for the proper identification and characterization of normal, displasic and neoplasic cells (OSBORN & WEBER, 1983; NAGLE). The different patterns of expression of keratins are related to the degree of differentiation of inmature epithelial cells, as well as the degree of differentiation of malignant tumours (FUCHS & GREEN, 1980; FRANKE et al., 1981b; MOLL et al, 1892a; SCHAAFSMA & RAMAEKERS, 1994). Lastly, evaluation of the changes of immunoexpresion of keratins is useful for the differential diagnosis between typical and atypical squamous metaplasia, including moderate and severe epithelial displasia and intraepithelial neoplasia -formerly known as carcinoma in situ- (MOLL et al., 1982a; TSENG et al., 1982; QUINLAN et al., 1985; HUSZAR et al., 1986; GIGI-LEITNER et al; HEID et al.,1988)