ABSTRACT
<p><b>OBJECTIVE</b>To investigate the development of xenografted primitive human germ cells by using fetal testicular tissues as donor tissues and an immunodeficient mouse as the recipient.</p><p><b>METHODS</b>Testicular tissue fragments of a 26-week fetus were grafted under the back skin of a castrated immunodeficient mouse. Grafts were taken out after 135 days and processed for morphological and histological analyses.</p><p><b>RESULTS</b>The mass of grafts grew from about 1 mm in diameter and 5 mg in wet weight to about 3 mm and more than 20 mg 135 days after grafting. Histological observations showed a significant expansion of seminiferous tubules after grafting (80 +/- 25 microm in diameter) in comparison with seminiferous cords at the time of grafting (60 +/- 15 microm in diameter). The seminiferous cords developed into seminiferous tubules with the epithelial border and lumen. After 135 days of grafting, most of the dispersedly distributed primitive Sertoli cells and germ cells migrated to the basal part of seminiferous epithelium, located on the basement membrane and few of germ cells differentiated into spermatogonia.</p><p><b>CONCLUSION</b>Human fetal testicular tissues could survive and continuously develop after being xenograft into castrated immunodeficient mice.</p>
Subject(s)
Animals , Humans , Male , Mice , Fetal Tissue Transplantation , Mice, Inbred BALB C , Mice, Nude , Spermatids , Testis , Cell Biology , Transplantation , Transplantation, HeterologousABSTRACT
To investigate the function of microtubules (MTs) in Sertoli cell, colchicine, a microtubule disrupting agents, was injected into the dorsum of the male SD rat. The seminiferous tubules and Sertoli cell of the rat were examined by light and electron microsopy. 5-6 hours after the colchicine injection the following results were revealed (1) The Sertoli cell of the rat testis showed prominent morphological changes. The processes of the cell retracted, the MTs disappeared in the cytoplasm and the distribution of mitochondria and smooth endoplasmic reticulum became irregular. (2) Many widened intercellulor spaces occured in the seminiferous epithelium; and accordingly the arrangement of the germ cells became deranged and the elongated spermatids moved form their original deep position to the surface of the epithelium. (3) There was no evident changes in the basal region of the seminiferous epithilium. These results confirmed that MTs in Sertoli cell are essential to the maintenance of the normal shape and cellular organelle arrangement in the cell as well as the architecture of seminiferous epithelium. They may also play an important role in the movement of the elongated spermatids.
ABSTRACT
The postnatal development of the ectoplasmic specialization (ES) of Sertoli cells was investigated in the rats from 1st to 8th week after birth and the adult by electron microscopy. At the end of the 1st week. ES is in the beginning of its formation. Some high electron dense materials accumulate in the submembranous regions and short cisternae of endoplasmic reticulum align in these zones. At the end of the 2nd week the short cisternae are fused each other and straight microfilaments bundles appear and are sandwiched between the flattened cisternae and cell membrane. The density of microfilaments is increased in the 3th week and numerous tight junctions appear between adjacent Sertoli cells. The ES is gradually completed in its structure until the 5th week and fully extend and circumscribed around the base of Sertoli cells. Thereafter, there is no more morphological changes. We conclude that the first 5 weeks after birth is the important period for the development of ES of Sertoli cell as well as the blood-testis barrier in rats.
ABSTRACT
The Sertoli cell-rich or Sertoli-germ cell aggregates of 15-21 day immature rat testis were cultured in serum-free Ham F-12 medium for observation of the reorganization of the seminiferous tubules in vitro. The results showed that after first week of culture, the cell aggregates were spreaded on the bottom of culture dish as a monolayer consisted of Sertoli cells as well as spermatogenic cells. While after second week these monolayer cell cultures rearranged and transformed into cellular cords which connected each other to form a cellular rete. During this time, there were many small cells with long cytoplasmic processes appeared in the cultures. They looked like immature spermatozoon-like cells which were released from the cellular cords and floated in the medium, however no movement was detected. After third week, the cellular cords developed into a solid or tubule-like structures consisted of Sertoli cells and spermatogenie cells in different stages of spermatogenesis.These cultures have been studied by phase-microscopy in vitro, light and electron microscopy on semithin and ultrathin sections. These studies revealed that the Sertoli cells and Sertoli-germ cell aggregates of immature rat testis, in vitro, not only developed into monolayer cell culture as mentioned, but were also able to be further reconstructed, or reorganized, in some extent, to solid and tubule-like structures. The possible significance and mechanism were discussed.
ABSTRACT
The secretion and localization of epididymal specific proteins ESP-1, ESP-2 were systematically studied by the PAGE-western blot and ABC immunocytochemical technique in the epididymis of the rabbit. The results indicated that ESP-1 and ESP-2 represented the rabbit epididymal specific proteins of 42 kd and 20 kd, respectively. They were immunoeytochemically negative in the testis, heart, liver, spleen, lung, kidney and skeletal muscle of the rabbit as well as testis and epididymis of the rat. However, in the rabbit epididymis, except the initial segment ESP-1 and ESP-2 were started to be positive from caput segment. The ESP-1 was displyed in the supranuclear area of the principle cells, while the ESP-2 was distributed evenly in the whole cytoplasm of it. Subsequently, the most heavy positive reaction was demonstrated in the corpus epididymis and the proximal segment of cauda. In contrast of the caput, the stereocilia of principle cells and lumen sperms of the cauda epididymis were positive also. However, in the distal segment of cauda the positive reaction in cytoplasm of principle cells was gradually decreased and became disappeared completely soon, while the stereocilia of it still remained heavy positive even in that of vas deferens. The epithelium of prostate gland and seminal vesicle were negative. These results indicated that both ESP-1 and ESP-2 were secretory proteins produced mainly in the principle cells of the corpus epididymis. After releasing into the lumen, they took part of epididymal fluid and might bind on the sperm to regulate sperm maturation. The possible physiological significance of ESP-1 and ESP-2 was discussed.
ABSTRACT
The distribution of microtubules (MTs)in the Sertoli cell of rat testis was studied with indirect immunofluorescence and electron microscopy. We have found that MTs are mainly located in the cytoplasm apical to the nucleus and oriented parallel to the long axis of the Sertoli cell. MTs may extend into the stalks and processes of the cell which embrace different germ cells. With the changes of the architecture of the seminiferous epithelium and the shape of Sertoli cells, there are some regular changes in MTs distribution during the seminifeous epithelium cycle. In stage Ⅰ-Ⅴ, many MTs aggregate around the elongated spermatids and are parallel to their long axis. During stage Ⅶ maturing spermatids are suspended into the lumen by the Sertoli cell processes containing numerous MTs. Some of the MTs conform to the contour of the hook-shaped spermatids heads. After spermiation (stage Ⅶ-Ⅸ), MTs retract from the lumen with the Sertoli cell processes and gather around the spermatids which just start their elongation. These results indicate that the distribution of the MTs in Sertoli cell has close relations with the architecture of the seminiferous epithelium, and the changes of the Sertoli cell shape and the movement of the spermatids.
ABSTRACT
The present study was designed to examine the toxic effect of gossypol on the heart, liver, kidney,adrenal and testis of the Wistar rats with the electron microscope. Gossypol was administered orally at a daily dose of 30mg/kg body weight for 1-3 weeks, the tissues were secured at various time intervals and prepared for observation. It was shown that no significant ultrastructural changes could be observed in the heart muscle, kidney, and adrenal of animals fed on gossypol at the dosage that had damaged to testis. The latter demonstrated obvious degenerative changes in spermatids and spermatocytes 3 weeks following treatment and appeared to be more sensitive to the effect of gossypol poisoning. Gossypol induced distension of the endoplasmic reticulum and caused an increases in amount of smooth endoplasmic reticulum as well as lysosomes of the hepatic cells. Other subtle ultrastructural changes in the hepatic cells including the decrease of glycogen granules, displacement of ribosomes from rough endoplasmic reticulum and the distension of canaliculi biliferi were also discernible. Based on the above results, the toxic efficacy of gossypol was analysed and discussed.
ABSTRACT
Testicular macrophages and Leydig cells were isolated from rat testis withtrypsin and collagenase treatment respectively.Peritoneal macrophages were obtainedfrom same species by peritoneal cavity lavage.When the testicular macrophages wereco-cultured with Leydig cells,the testosterone secretion was increased and themagnitude of the increased testosterone secretion was directly related to the numberof macrophages added to the cultures(control:6.3?1.5 pmol/10~6 cells,co-culture:9.1?0.9 pmol/10~6 cells,mean?SE,p