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  • 1
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 130 (1958), S. 477-495 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Zusätzliches Material: 3 Tab.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 149 (1964), S. 411-433 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The distribution and origin of interstitial tissue has been studied in various mammalian ovaries with histochemcal techniques for lipids. The interstitial tissue contains sudanophilic droplets of different sizes consisting of phospholipids, triglycerides and cholesterol and its esters; the lipids are comparatively unsaturated.The granulosa of normal follicles contains heterogeneous lipid bodies of various sizes composed of unsaturated phospholipids. With the start of atresia these lipid bodies also develop neutral fats (triglycerides). Besides the heterogeneous lipid bodies, another type of sudanophilic lipid droplets of atresia, consisting of triglycerides, cholesterol and its ester and little phospholopids, are formed in the granulosa cells. When the number of these lipid droplets is sufficiently increased, the heterogeneous lipid bodies disappear from the atretic follicles. The theca of such atretic follicles hypertrophies and persists to form the interstitial tissue whereas the granulosa cells, along with the lipid droplets, regress and disappear.In the rat ovary, the interstitial tissue occurs as scattered patches of various sizes that are derived from the theca of atretic preantral and antral follicles. Most of the lipid droplets of the interstitial tissue are mobilized from the preovulatory rat ovary. All of the bat ovary is occupied by interstitial tissue except for the cortex; the tissue is formed in the same way as in the rat. In the cat ovary, the interstitial tissue is sparsely scattered between the follicles and originates from the theca and adjacent stromal cells of normal and atretic follicles. In the dog ovary the interstitial tissue has a similar origin and also arises from invaginations of germinal epithelium. In the opossum ovary the interstitial tissue is present in the form of sparsely scattered patches of cells which arise from the theca of large preantral follicles. A few lipid bodies, consisting of unsaturated phospholipids, appear in the interstitial tissue.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 157 (1967), S. 163-172 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The effect of exogenous estrogen on tubal transport of ova was determined in the guinea pig, hamster, mouse, rabbit and rat. The animals were given a single injection of estradiol cyclopentylpropionate (ECP) shortly after mating. The dose of ECP required to interrupt pregnancy in 80% or more of the animals was as follows: guinea pig (10 μg); hamster (25 μg); mouse (1 μg); rabbit (50 μg); rat (10 μg). Acceleration of egg transport through the oviduct occurred after the following doses of ECP: guinea pig (50-100 μg); hamster (100 μg); mouse (1 μg and above); rabbit (25 μg); rat (10 μg and above). Hence, the amount of estrogen which accelerates egg transport in the guinea pig and hamster is considerably higher than the dose which interrupts pregnancy.Retentionof ova for longer than the normal period of tubal passage (tube-locking) resulted from the following doses of ECP: guinea pig (250 μg); hamster (250 μg); mouse (1 μg); rabbit (100 μg); rat (no dose). In the species in which ova were tubelocked, the majority of eggs were located at the ampullary-isthmic junction rather than the utero-tubal region of the oviduct.Tube-locking of ova was never observed in the rat; ECP always caused premature entry of eggs into the uterus and eventual expulsion per vaginam. For example, eggs passed through the cervix by 12 hours after the administration of 250 μg ECP at day 1 of pregnancy.
    Zusätzliches Material: 13 Tab.
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 163 (1969), S. 373-387 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: Pregnant mice were hypophysectomized on day 6 and injected subcutaneously with various hormones from days 6 to 9 to establish the minimal requirements for the maintenance of functional corpora lutea. Luteal activity was assessed by the maintenance of pregnancy, weight of embryonic swellings, mean diameter and morphology of corpora lutea, and vaginal histology.Treatment with 2 mg progesterone maintained pregnancy but not corpora lutea in three of five animals. However, the embryonic swellings were significantly (P 〈 0.0005) smaller than those of pregnant control animals. Pregnancy was maintained in all animals when progesterone was combined with 1 μg of estrone. The weights of embryonic swellings and the degree of vaginal mucification in the combined steroid group were similar to those of intact control animals.Treatment with either ovine prolactin, bovine LH, ovine FSH or estrone failed to maintain corpora lutea or pregnancy. Combined injection of prolactin with LH or estrone did not maintain pregnancy or corpora lutea. On the other hand, treatment with 500 μg of prolactin and 200 μg of FSH maintained pregnancy in 12 of 14 animals. All of the aforementioned parameters of luteal activity were comparable to values in intact, control animals.The data indicate that luteal function in the mouse during the early post-implantation period requires a luteotropic complex rather than a single hormone. Prolactin and FSH constitute the minimal luteotropic complex in the pregnant mouse. The luteotropic activity of FSH was not due to its contamination with LH and the effect of FSH was apparently not mediated through estrogen secretion, since pregnancy was not maintained by prolactin and estrone.
    Zusätzliches Material: 5 Tab.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 171 (1971), S. 221-225 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: Unilateral ovariectomy of hamsters on day 1 of pregnancy resulted in an increase in weight of the remaining ovary by day 4, primarily by increasing the number of antral follicles. The ovulability of these follicles was tested by injecting 20 IU human chorionic gonadotropin (HCG) on day 12 of pregnancy. Following this treatment, the unilaterally ovariectomized animals ovulated 29.4 eggs whereas intact animals ovulated 16.6 eggs per ovary. In both instances, the number of antral follicles ovulated by HCG was between 40% and 50% of the number present. Luteal weight was unaltered by semispaying, indicating that the regulation of corpus luteum growth does not fit a negative feedback system.The ability of exogenous steroids to prevent ovarian compensation was assessed by injecting either progesterone (2 mg) or estradiol cyclopentylpropionate (1 μg) daily from days 8 to 11 of pregnancy. Either steroid injected into the semispayed hamsters prevented the expected increase in the remaining ovary in weight, follicular development and the ovulatory response to HCG. The same hormonal treatment of intact, pregnant animals slightly increased mean ovarian weight but did not affect follicular development.These results suggest that unilateral ovariectomy of the pregnant hamster, by decreasing peripheral level of ovarian steroids, partially reduces the inhibition of gonadotropin secretion and therefore leads to ovarian compensation.
    Zusätzliches Material: 4 Tab.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 188 (1977), S. 331-337 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The time required for ovarian follicular development in the cyclic hamster was determined by marking follicles with [3H]-thymidine on day 1 of the estrous cycle (day of ovulation) and by following their fate over the next three cycles by autoradiography. A model of follicular development was formulated, based on the total number of follicles and the changing percentage of labelled follicles with time.It was estimated that 20 days elapsed before a preantral follicle with two to three layers of granulosa cells (stage 1) was able to ovulate. Follicles spent eight days in stage 1 and an additional eight days in stage 2 (4-5 granulosa layers). Preantral follicles entering stage 3 (6-7 granulosa layers) and 4 ( 8 layers) on day 1 of the cycle ovulated four days later.Approximately 30 follicles per ovary entered and left stage 1 each cycle, representing a 50% turnover. Of the follicles leaving stage 1, about 50% were transformed into stage 2 follicles; the remaining ones underwent atresia. Stage 2 follicles also had a 50% turnover each cycle. Half of the stage 2 follicles underwent atresia; the remainder developed into stages 3 and 4 follicles Fifty percent of the stages 3 and 4 follicles present on day 1 of the cycle ovulated at the next estrus with the remainder undergoing atresia.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
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  • 8
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 9
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 148 (1964), S. 171-176 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: A control group of guinea pigs ovulated 3.43 ± 0.41 ova or 1.72 ova per ovary. Unilateral ovariectomy (semispaying) on day 1 resulted in the ovulation of 3.71 ± 0.37 ova from the remaining ovary, whereas after semispaying on days 5 and 10, 2.80 ± 0.12 eggs were ovaluated. Unilateral ovariectomy during days 12, 14 and just prior to ovulation resulted in the same number of ova being ovulated from the remaining ovary as from the initial ovary removed. Semispaying at any day during the cycle did not alter cycle length.At day 1, all follicles from the previous cycle were atretic. At day 5 the current population of follicles were well developed with no atresia present. Ovaries removed on days 5, 10, and 12 had approximately the same distribution of large follicles with atresia appearing in all size ranges. At day 14, the number of large follicles was markedly decreased. However, after semispaying at day 5, the remaining ovary at day 14 had twice the number of Graafian follicles and twice the amount of atresia in these size ranges as the normal day 14 ovary.It is therefore likely that the compensatory response after unilateral ovariectomy in the guinea pig is due to an increase in the rate of proliferation of smaller sized follicles into larger ones. Day 12 seems to be the critical period of the guinea pig cycle. At this time, regression of the corpora lutea occurs, and perhaps of significance, the ability of the animal to compensate for unilateral ovariectomy is also lost.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 10
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 161 (1968), S. 447-457 
    ISSN: 0003-276X
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin
    Notizen: The ovary of the newborn hamster is characterized by numerous oogonia which are undergoing mitotic divisions. By day 8, the germ cells have developed into oocytes (dictyate stage). The oocytes and granulosa cells are surrounded by an undeveloped network of fibrous stromal cells until day 14. Between days 14 and 21, the stroma is transformed by hypertrophy and hyperplasia into a primary interstitium consisting of large epithelial cells.The critical period of follicular development is from days 21 to 28, with antral follicles first appearing on day 26. The earliest spontaneous ovulations occur on day 29. This differs from the temporal relationship in the rat and mouse in which antral follicles not only develop several weeks before puberty but can also be induced to ovulate prematurely with exogenous gonadotropins. In contrast, in the hamster the maximal ovulatory response to pregnant mare's serum (PMS) develops rapidly between days 27 to 30. Over this period, induced ovulations increase from an average of 10.5 ova to 55 eggs. The altered responsiveness to PMS does not correlate with any change in the diameter of follicles or number of secondary or tertiary follicles. It is therefore concluded that progressively smaller follicles become competent to respond to exogenous gonadotropin between days 27 and 30.
    Zusätzliches Material: 5 Tab.
    Materialart: Digitale Medien
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