THE USE OF JAPANESE FROGS IN THE DIAGNOSIS OF PREGNANCY : VI. EXPERIMENTS IN VITRO AND HISTOLOGICAL STUDIES ON THE MECHANISM OF SPERMIATION IN THE FROG

Abstract

1. According to VAN 0ORDT et al., the release of sperm cells took place in a hypotonic Ringer solution, but no spermiation was observed in a hypertonic Ringer solution. Similar results were obtained with water, hypo- and hypertonic saline solutions (Chart 1). 2. One of the testes of a frog was placed in a saline solution containing the spermiation causing agent, and the other one in a saline solution only, and tests in vitro, were carried out. An adenohypophysis of the frog in 2 cc of 0.645% saline solution caused a rapid in-increase in the testis' weight and spermiation, in the opposite testis, placed in 0.645% saline solution only, a negative result was obtained. 3. It is considered important that HCG and epinephrine in a slightly hypertonic saline solution, caused weight increase and spermiation, while the weight of the opposite testis of the same frog in a saline solution of the same concentration without such agents decreased, and no spermiation took place (Chart 2). 4. Seasonal variation of the fluid uptake by the testis was observed (Chart 3). Rapid spermiation occurred with a slight increase of the testis' weight during the breeding season, indicating that the testis had already taken up water from the surrounding blood capillaries under the stimulus of the endogenous spermiation causing factor which had probably been secreted from the "purple cells" of the adenohypophysis, as already reported. On the contrary, spermiation did not always occur in spite of the intense weight increase during the summer, -the period of sexual rest. This seasonal variation showed a parallel relation with that of the sensibility of the frog in vivo, as already reported. 5. Histamine caused no water uptake nor spermiation in a slightly hypotonic saline solution. 6. A bovine feces extract, after Banik's method, diluted four times with 0.909% saline, proved to be a little more hypertonic than 0.769% saline solution, and caused a slight water uptake, -sperm cells being released in a few cases when several tests were made in vitro. 7. Dibenamine, of 10^-3 or 10^-4 concentration, in an isotonic saline solution, inhibited the water uptake and the spermiation causing activity of epinephrine and HCG, in vitro, as reported in the case of the toad, by TAKAGI. 8. Vacuoles in the Sertoli Cells, and enlargement of the cytoplasm of these elements, were observed in the sections of the spermiated testes, as DE ROSERTIS et al. and VAN 0ORDT et al., reported. 9. Small eosinophilic granules were observed in the Sertoli cells of the spermiated testis by DE ROBERTIS et al. Eosinophilia of the interstitial tissue, and the cytoplasm of the Sertoli cells was observed in my observation while both structures remained rather basophilic after Carnoy's fixation, in the control testis. 10. RNA of the interstitial tissue and in the reacted tubules, decreased or disappeared in the spermiated testis. It is interesting that RNA was found in the interstitial connective tissue of the testes of the frog when it had not been found in the ordinary connective tissue. 11. Fluid uptake and spermiation, even in a slightly hypertonic saline solution containing HCG or epinephrine, as stated in 3, can not be explained by only the osmotic pressure. Hydrolysis of RNA in the interstitial tissue, and in the tubules, might be significant as one of the "chemical reactions" supposed to have taken place in the testis. Eosinophilia, observed in the interstitial tissue and Sertoli cells of the spermiated testis, might have resulted from the disintegration of ribonucleoprotein into RNA and eosinophilic proteins, such as protamine of histone. 12. [the rest omitted]