Spermatogenetic Activity Research Articles

Histological observations on the seasonal changes in the testis of a lizard, <i>Eumeces latiscutatus</i>

Seasonal spermatogenetic changes were observed in the testis of a lizard, Eumeces latiscutatus, common in Japan-Hondo. During the months of April, May and early June, all spermatozoa are eliminated from the seminal tubules. Spermatogonial divisions occur in May and June. Primary and secondary spermatocytes and maturation divisions appear through July and August. Spermioteleosis is practically completed during from late November to December. During hibernation, there is no spermatogenetic activity in the testis.

Notes on the seasonal spermato-genetic cycle of a gecko, <i>Hemidactylus flavoviridis</i>, from India

The present paper deals with the observations on the seasonal spermatogenetic cycle in the testis of a gecko, Hemidactylus flavoviridis, collected in India through the year. Evidence presented indicates that there is no remarkable seasonal variation in the spermatogenetic activity throughout the year. Active spermatogenesis uniformly occurs in every season of the year.

Histological manifestations of feeding polyoxyethylene monostearates. to weanling hamsters.

SummaryA histological study of the duodenum, ileum, rectum, liver, kidney, testis and bone marrow of weanling hamsters fed on a basal diet containing 5 or 15% polyoxyethylene monostearates (Sta-soft or Myrj) soft after 2-10 weeks on experiment. Histological changes observed in the small intestine, particularly the ileum, consisted of a severe erosion of the mucosa. Necrosis of the liver, decreased spermatogenetic activity of the testis, and tubular degeneration of the kidney were also observed.

A Study of the Testis Tubules, Interstitial Tissue, and Sex Characters (Thumb-pads and Wolffian Ducts) of Normal and Hypophysectomized Frogs (Rana esculenta)

ABSTRACT 1. After hypophysectomy in October the testes and some sex characters (Wolffian ducts and thumb-pads) of Rana esculenta were investigated during 9 subsequent months. 2. The so-called prespermatogenesis (Champy, 1913) is completed normally after hypophysectomy, but the primary spermatogonia lose their capacity for division. Therefore 8 months after the operation the testis tubules contain only primary spermatogonia. 3. The spermatogonia of the testes of control frogs, kept under laboratory conditions from October onwards, show a precocious activity during the winter, but in July new spermatozoa have not yet been formed. 4. In both control and experimental frogs the spermatozoa, formed during late summer and autumn, almost entirely disappear in the spring, even in the absence of copulations. 5. During the winter and spring months the interstitial testis cells of the control frogs undergo a reduction in both number and function, and this coincides with the increased activity in the testis tubules which occurs under laboratory conditions. 6. Conversely the decreased spermatogenetic activity, caused by hypophysectomy, coincides with an increase in the number of interstitial cells. The cytoplasm of these cells, however, is greatly reduced, although the nuclei maintain their typical form and size till at least 9 months following the operation. 7. Thumb-pads and Wolffian ducts are strongly affected by hypophysectomy. 8. The cytological changes brought about in the interstitial cells of R. esculenta after hypophysectomy do not quite coincide with changes in the development of the thumb-pads and Wolffian ducts. Therefore no new evidence for the endocrine function of these cells can be given.

脊椎動物睾丸の間細胞に就て

(1) The origin and fate of interstitial cells in the testis of the following animals were confirmed by histological study:Adult vertebrates:Middle Yorkshire swine. Frog (Rana nigromaculata HALLOWELL). Toad (Bufo vnlgaris japonicus SCHLEGEL). Water-lizard (Diemyctylus pyrrhogaster BOIE). Roach (Akahara Hahoneusis GÜNTHER).Young frogs. Pigs. Pig embryos.For the purpose of comparison with vertebrates, the testis of locusts (Oxya japonica WILLENSE, O.velox Fabricus) and silk worms (Bombyx mori Linnaeus) were also sectioned.(2) In silk worms, there exist no cells corrsponding morphologically to Leydig's cells as in mammals.(3) In water-lizards there are isolated interstitial cells found, as well as these groups, surrounded by thin fibrinous membane.(4) The development of interstitial cells delay in some degree, as compared with the increase of germinal elements.(5) It is proved that interstitial cells are of the manifold origin, in general stroma as well as Sertoli and follicle cells being the main sources of their formation.a) The majority of interstitial cells arise from stroma cells in most animals, except those of the testes of ducks of which the considerable number of them spring from Sertoli cells.b) In all animals, so far as investigated, Sertoli and follicle cells may be converted into interstitial cells. This process is correlated with the degeneration and resorption of germ cells, probably due to the physiological action of the readjust ment of spermatogenesis. in accordance with the development of testis.c) It would seem also proboble that interstitial cells are derived from cells of the Tunica propria of the spermatic tubules at least in urodeles, roaches and locusts and presumably those of anurans, in addition epithelial elements of the sperm collecting ducts in frogs and toads.(6) There exist two stages of proliferation of interstitial cells in pigs in an embryonic life, of which the first one is of 37 days old and the second is 100 days old.(7) Great variability occurs in number and size of interstitial cells during yearly spermatogenetic cycle. In ducks, it is reduced to a minimum near the height of spermatogenetic activity, that is, shortly before gradual return to completely inactive conditions of the non-breeding season, when testis begin to decrease in size and interstitia cells get more difficult to recognize as such and they are almost lacking in some testis.Although, in other adult animals, the number of them, having the cytoplasm filled with a great number of mitochondria and droplets of fat as well as well-developed Golgi apparatus are greatest and the testis are supplied abundantly with blood vessels during the breeding season and at the time when young animals reach the full sexual maturity.(8) The appearance of the secondary sexual characters precede the great increase in number of interstitial cells, at the time when the testis is in complete spermatogenetic activity, with the presence of mature spermatozoa in almost every sperrnatogenic tubules.(9) The stage of the maximam number and secretory activity of interstitial cells is simultaneous with the stage of the intense appearance of the typical feature of the secondary sexual characters and later on, there seems to be parallel relationship between them.(10) In adult animals, there are ldcal variations in the spermatogenic activity in the same testicle. Interstitial-cell changes bear the reverse relation to conditions of germinal elements; that is to say, interstitial cells develop only when spermagenic tubules are inactive and intertubular spaces wide, and then gradually regress when tubules are in active spermatogenesis and intertubular spaces narrow.

光が鶩睾丸に及ぼす影響に就て

This studiy was completed on December 18, starting on July 19, 1943. Besides the natural daylength of light the experimental light conditi ons were regulated by using two 60watt incandescent bulbs placed one meter above the center of the floor and in dark rooms. For the group I, the daily lengtn of exposure to light was increased suddenly up to 15 hours until the termination of this precocious experiment on August 31. Thereafter the night lighting was reduced by approximately 10 minutes a day every three days until the animals were given daily 9 hours of lighting. For the group II, the experiment was made in a completely opposite direction. In the last group, the ducks, not artificialy stimulated, derved as control.1. From the above mentioned observations it is clearly confirmed that spermatogenetic activity in the duck is controlled by light periods and the minimum photoperiod of a day necessary for the induction of the, male sexual maturity is from 12 hours to 13hours.2. Decreased illumination was not always effective in suppressing gonadal growth. In spite of the sudden or gradual reduction in the total light ration down to 9 hours daily, the testicular activation in the majority was so pronounced that there were observed few spermatozoa in the seminiferous tubules.3. The moulting was caused most strikingly by a sudden reduction of the long daily photoperiod, despite the fact that some of the testis were yet in full sexual activity.4. The body weight was greatest when the daily period of exposure to light was shorter than that which induced the maximum development of spermatogenesis.

The Occurrence of Oviform Germ Cells by Hormonal Injection in the Regenerated Testes of a Newt

a) Triturus pyrrhogaster has multiple testis made up of two or more small successive lobes. In each testicular lobe certain wave of germ cell differentiation proceeds in cephalo-caudal direction. The spermatogenesis begins at the cephalic end of the lobe and the more the tubules shift caudally they contain the germ cells of the more advanced stages and its caudal end is occupied by the senescent tissue which had extruded the reproductive products in the preceding breeding cycle. At the cephalic apex of the lobe there remains permanent embryonal tissue which supplies the germ cells in the succeeding breeding season. The last named region is readily distinguishable as a white crest at the apex of the lobe.b) When the male is incompletely castrated the tissue of white crest regenerates very well. Spermatogenesis performed in the regene-rated testis agrees in general with that in the normal male.c) The white crest of the testicular lobe regenerates equally well, whether grafted in completely castrated male or female. Grafts from the central region of the testis containing only matured spermatozoa degenerate and eventually disappear.d) In a small number of regenerated testes oviform germ cells of various sizes differentiated intermingling with matured spermatozoa.e) When incompletely castrated male was injected with pelanin benzoate, a preparation of crystalline follicular hormone dissolved in sesame oil, differentiation of oviform germ cells occurred in the majority of cases to a considerably high degree. The injection was executed every month over the range of about one year. Some oviform cells appeared singly in the intervening tissue of seminiferous tubules, others within the confines of tubules, but those developed in the broad connective tissue zone of rather abnormally regenerated testes were largest in size as well as in number. In an extreme case about two-thirds of the entire volume of the regenerated testis was packed with oviform cells of various sizes. The seminiferous tubules neighbouring the connective tissue containing oviform cells are more or less retarded in their spermatogenetic activity.

PREGNANCY TEST USING THE MALE TOAD

IN THIS report a new pregnancy test is described, in which the male toad (Bufo arenarum Hensel) is used as the reacting animal. The positivity or negativity of the test is determined by the presence or absence of spermatozoa in the urine of the toad previously injected with the urine of a woman suspected to be pregnant. The spermatozoa of the adult toad are in contact with the Sertoli cells and are grouped together, parallel to each other, in such a way that they appear like bundles. Occasionally the spermatozoa are free and detached from the wall of the tubes and can be seen as a loose skein. The relation between the pituitary and the testis of Bufo arenarum Hensel has been studied by Houssay and Lascano Gonzalez (2). These authors found evidence that in the toad the pituitary exerts a constant influence upon the spermatogenetic activity of the testis, and that removal of the pituitary produces testicular atrophy. Repeated subcutaneous implantation of toad pituitary caused testicular hypertrophy in norma...

SOME EFFECTS OF SEX STEROIDS ON THE GONADS OF THE STARLING12

DESPITE many studies, the effects and actions of sex steroids on the avian gonad are not understood clearly. Moore and Morgan (1942) and Lahr and Riddle (1944) have summarized much of the literature. A bird such as the starling offers advantages for study because by photoperiodic manipulations the testis can be placed at a desired level of spermatogenetic activity whereby the annual cycle can be studied in its individual parts. A previous study on the starling (Burger 1944) found that testosterone delayed the response of the initially inactive testis to the stimulation evoked by “long days.” This exogenous steroid did not effect spermatogenesis in testes which were already producing sperm. In the present study, some effects of estradiol and further effects of testosterone are reported. Of special interest is the response, novel for the bird, of the testis to estradiol. Table 1 records the various experimental treatments. Of the two light rations used, 14 hours daily light (long days) will induce complete ...

SOME EFFECTS OF ANDROGENS ON THE ADULT MALE FUNDULUS

Adult male Fundulus hypophysectomized during the breeding season were injected intraperitoneally with 8 mg. of testosterone propionate during a 42 day period. The hormone maintained the yellow body coloration characteristic of a breeding male. The hormone did not maintain the testis in the breeding condition. The testicular ducts were maintained better than they were in the controls. There was slightly more spermatogenetic activity than in the controls. Like amounts of testosterone injected intraperitoneally into normal fish over a similar period had no effect on the testis and only partially maintained the yellow coloration of the body.Normal adult male fish injected intraperitoneally or intramuscularly with testosterone propionate (see text for dosage) during testicular involution and during the early stages of spermatogonial multiplications showed a marked activation of the testicular ducts and a slight stimulation of spermatogenesis. The yellow coloration of the body developed brilliantly in the treat...

SOME EXPERIMENTS ON THE RELATION OF THE EXTERNAL ENVIRONMENT TO THE SPERMATOGENETIC CYCLE OF FUNDULUS HETEROCLITUS (L.)

Within the last decade a considerable body of experimental work has shown that the sexual cycles of many vertebrates of the north temperate zone are regulated in part by the annual cycle of changes in day-length. Little, however, is known about the relation of the ex ternal environment to the sexual cycle of cold water fish. Success in modifying the piscine sexual cycle by light agencies has been reported for the trout (Hoover, 1937; Hoover and Hubbard, 1937), for the minnow, Phoxinus (Spaul cited from Rowan, 1938), and for the stickle back (Tinbergen cited from Rowan, 1938). Craig-Bennett (1930) came to the conclusion that the sexual cycle of the stickleback was regulated primarily by temperature. Hoover (private communication to T. H. Bissonnette) has found that light is ineffective on yellow perch which were kept in water below 44°F. The normal sexual cycle of Fundulus has been described by Mat thews (1938). As in many cold-blooded vertebrates the sexual cycle is a continuous process throughout, with no genuinely inactive phase, although during the winter there is little or no spermatogenetic activity. In the late summer and fall a limited production of spermatogonia takes place. Vigorous spermiogenesis begins in the spring, with a mating period during May and June. Thereafter occurs a gradual deceleration of spermiogenesis with a concomitant testicular involution. It is noticed that the major portion of the spermatogenetic activity is present during the spring when the days are increasing in length, and when the temperature of the water is rising. The experiments here reported are to test the relation of light and temperature to the spermatogenetic cycle of Fundulus.

Note on a Subcutaneously Transplanted Mouse Testis with Spermatogenetic Activity

Note on a Subcutaneously Transplanted Mouse Testis with Spermatogenetic Activity