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Seekallu S, Toosi B, Zeigler A, Rawlings N. Effects of estradiol and progesterone on circulating LH and FSH secretion, and ovarian antral follicle growth in anestrous ewes. Small Rumin Res 2010. [DOI: 10.1016/j.smallrumres.2010.03.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Duggavathi R, Bartlewski PM, Barrett DMW, Rawlings NC. The temporal relationship between patterns of LH and FSH secretion, and development of ovulatory-sized follicles during the mid- to late-luteal phase of sheep. Theriogenology 2005; 64:393-407. [PMID: 15955361 DOI: 10.1016/j.theriogenology.2004.12.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2004] [Indexed: 11/25/2022]
Abstract
The aim of the present study was to investigate the temporal relationship between the secretory pattern of serum LH and FSH concentrations and waves of ovarian antral follicles during the luteal phase of the estrous cycle in sheep. The growth pattern of ovarian antral follicles and CL were monitored by transrectal ultrasonography and gonadotropin concentrations were measured in blood samples collected every 12 min for 6 h/d from 7 to 14 d after ovulation. There were two follicular waves (penultimate and final waves of the cycle) emerging and growing during the period of intensive blood sampling. Mean and basal LH concentrations and LH pulse frequency increased (P < 0.001) with decreasing progesterone concentration at the end of the cycle. Mean and basal FSH concentrations reached a peak (P < 0.01) on the day of follicular wave emergence before declining to a nadir by 2 d after emergence. None of the parameters of pulsatile LH secretion varied significantly with either the emergence of the final follicular wave or with the end of the growth phase of the largest follicle of the penultimate wave of the cycle. However, mean and basal LH concentrations did increase (P < 0.05) after the end of the growth phase of the largest follicle of the final follicular wave of the cycle. Furthermore, the end of the growth phase of the largest follicle of the final wave coincided with functional luteolysis. In summary, there was no abrupt or short-term change in pulsatile LH secretion in association with the emergence or growth of the largest follicle of a wave. We concluded that the emergence and growth of ovarian antral follicles in follicular waves do not require changes in LH secretion, but may involve changes in sensitivity of ovarian follicles to serum LH concentrations.
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Affiliation(s)
- Raj Duggavathi
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Sask., S7N 5B4, Canada.
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Duggavathi R, Bartlewski PM, Barrett DMW, Gratton C, Bagu ET, Rawlings NC. Patterns of Antral Follicular Wave Dynamics and Accompanying Endocrine Changes in Cyclic and Seasonally Anestrous Ewes Treated with Exogenous Ovine Follicle-Stimulating Hormone During the Inter-Wave Interval1. Biol Reprod 2004; 70:821-7. [PMID: 14627553 DOI: 10.1095/biolreprod.103.023739] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
In the ewe, ovarian follicular waves emerge every 4 to 5 days and are preceded by a peak in FSH secretion. It is unclear whether large antral follicle(s) in a wave suppress the growth of other smaller follicles during the inter-wave interval, as is seen in cattle. In this study, anestrous (n = 6; experiment 1) and cyclic (n = 5; experiment 2) Western white face ewes were given ovine FSH (oFSH) (0.5 microg/kg; two s.c. injections, 8 h apart) during the growth phase (based on ultrasonography) of a follicular wave (wave 1). Control ewes (n = 5 and 6, respectively) received vehicle. In oFSH-treated ewes, serum FSH concentrations reached a peak (P < 0.05) by 12 h after oFSH treatment, and this induced FSH peak did not differ (P > 0.05) from the endogenous FSH peaks. In all ewes, emergence of follicular waves 1 and 2 was seen (P > 0.05). However, in oFSH-treated ewes, an additional follicular wave emerged approximately 0.5 days after treatment: during the interwave interval of waves 1 and 2 without delaying the emergence of wave 2. The growth characteristics and serum estradiol concentrations did not differ (P > 0.05) between oFSH-induced waves and waves induced by endogenous FSH peaks. We concluded that, unlike in cattle, the largest follicle of a wave in sheep has limited direct effect on the growth of other follicles induced by exogenous oFSH. In addition, the largest follicle of a wave may possibly not influence the rhythmicity of follicular wave emergence, as it does in cattle.
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Affiliation(s)
- Raj Duggavathi
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4
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Macfarlane MS, Breen KM, Sakurai H, Adams BM, Adams TE. Effect of duration of infusion of stress-like concentrations of cortisol on follicular development and the preovulatory surge of LH in sheep. Anim Reprod Sci 2000; 63:167-75. [PMID: 10989227 DOI: 10.1016/s0378-4320(00)00179-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Stress-like levels of cortisol suppress follicular growth and development and block or delay the preovulatory surge of LH when cortisol is continuously administered during the late luteal and early follicular phases of the ovine oestrous cycle. We postulated that cortisol infusion of shorter duration would have a similar effect. To test this hypothesis the oestrous cycles of mature ewes were synchronized using progestin-treated vaginal pessaries. Ewes were randomly assigned to one of four treatment groups. Animals received cortisol (0.1mg/kg/h; n=8) or vehicle alone (n=8) beginning 5 days before, and continuing for 5 days after, pessary removal (PR). Additional groups received cortisol only during the 5 days period before (n=7), or the 5 days period after (n=8), PR. Continuous delivery of cortisol established stable serum concentrations of cortisol of 72.0+/-2.5ng/ml within 6h of initiation of infusion. Serum concentrations of oestradiol increased progressively during the period after PR in control animals receiving vehicle alone and the preovulatory surge of LH was evident in all control animals (eight of eight) 55.5+/-5.0h after PR. In contrast, follicular development and the preovulatory surge of LH were evident during the period of cortisol infusion in only one of eight animals receiving stress-like levels of cortisol over the entire 10-day infusion period. Similarly, neither follicular development nor surge-like secretion of LH were evident during the infusion period in animals (zero of eight) receiving cortisol during the 5-day period after PR. This cortisol-dependent suppression of ovarian activity in sheep receiving stress-like levels of cortisol during the 5 days after PR was temporary and follicular development, the ovulatory surge of LH, and subsequent luteal function were evident in six of eight ewes after cessation of cortisol delivery. Similarly, follicular development and the preovulatory surge of LH were noted within 5 days after PR in four of seven ewes receiving cortisol only during the 5-day period prior to PR. Collectively, these data indicate that stress-like levels of cortisol reduce fertility of sheep by suppressing follicular development and the preovulatory surge of LH. Additionally, cortisol delivery during the follicular phase has a more profound suppressive effect on follicular development than cortisol administration during the luteal phase.
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Affiliation(s)
- M S Macfarlane
- Department of Animal Science, University of California, Davis, CA 95616, USA
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Yu SJ, Chen BX. Peripheral plasma concentrations of luteinizing hormone, oestradiol-17beta and progesterone around oestrus in six yaks. Vet J 2000; 160:157-61. [PMID: 10985809 DOI: 10.1053/tvjl.2000.0494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- S J Yu
- Department of Veterinary Medicine, Gansu Agricultural University, Lanzhou, Gansu, Peoples Republic of China
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Gonçalves SC, Marques CC, Stöckemann K, Wang W, Horta AE. Influence of an antiprogestin (onapristone) on in vivo and in vitro fertilization. Anim Reprod Sci 1997; 46:55-67. [PMID: 9231247 DOI: 10.1016/s0378-4320(96)01600-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effects of a progesterone antagonist (onapristone) on heat synchronization, luteinizing hormone (LH) surge, ovulation, oocyte maturation and fertilization of superovulated ewes were studied. Its effects on in vitro bovine oocyte maturation and fertilization were also studied. Estrus synchronization and superovulation treatments were applied to 39 adult ewes using an intravaginal sponge with fluorgestone acetate for 9 days with injections of prostaglandin F2 alpha and pregnant mare's serum gonadotrophin given 24 h before sponge withdrawal. The animals were randomly assigned to four different groups; T1 receiving only the synchrony treatment (n = 11); T2 ewes received two injections of onapristone (1 mg kg-1, i.v.) 12 h apart from 3 h after sponge withdrawal (n = 10); T3 ewes received two injections of progesterone 12 h apart from sponge withdrawal (n = 10); and, T4 ewes received both onapristone and progesterone as described (n = 8). Ewes were mated by a fertile male during estrus. Progesterone and LH were measured during the superovulation period in plasma samples taken every 4 h. Uterine flushings for ova recovery were performed at 5 days (n = 25), 48 h (n = 5) and 24 h (n = 5). Non-fertilized oocytes collected at 24 and 48 h were checked for meiosis resumption. The effects of two doses of onapristone (D1 and D2) on in vitro bovine oocyte maturation (control = 100, D1 = 100 and D2 = 100) and fertilization (control = 107, D1 = 40 and D2 = 75) were also studied. The percentage of animals showing heat signs was significantly lower in group T3 (50% vs. 100%). The onset of oestrus (27.6, 24.8, 68.8 and 25.5 h, respectively for T1, T2, T3 and T4) and an LH surge (32.3, 28.8, 76.5 and 30.5 h, respectively for T1, T2, T3 and T4) after sponge withdrawal were significantly delayed in group T3. There were no significant differences in the intervals between estrus and LH surge among groups (4.61 +/- 0.75 h). The response and ovulation rates until 40 h after sponge withdrawal (group T3 excluded) were similar among groups, but the fertilization rates were significantly lower in groups T2 and T4 when compared with T1 (2% and 3% vs. 41%, respectively; P < 0.001) due to sperm arrest in the cervix. Ova recovery rate decreased significantly from 24-48 h to 5 days and was not affected by treatments (76.9% vs. 37.1% respectively). Onapristone did not affect the resumption of meiosis. Fertilization of bovine oocytes in vitro decreased significantly only in group D2 when compared to control (48% vs. 62.6%, respectively). In conclusion, onapristone treatment during the preovulatory period did not interfere with normal synchronization of estrus, ovulation and oocyte maturation but severely compromised fertilization by arresting spermatozoa in the cervix.
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Affiliation(s)
- S C Gonçalves
- Departamento de Reprodução, Estação Zootécnica Nacional, INIA, Santarém, Portugal
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Mori T, Nihnobu K, Takeuchi S, Onho Y, Tojo S. Interrelation between luteal cell types in steroidogenesis in vitro of human corpus luteum. JOURNAL OF STEROID BIOCHEMISTRY 1983; 19:811-5. [PMID: 6887899 DOI: 10.1016/b978-0-08-030771-8.50116-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Slices of human corpora lutea of menstruation at different stages, or of inner and outer layers consisting of pure granulosa lutein cells and combined theca and granulosa lutein cells respectively, were incubated with [4-14C]-pregnenolone or with [4-14C]-androstenedione respectively. Conversion of 14C-radioactivity to progestins, androgens and/or estrogens was assessed by the reverse dilution technique with recrystallization to constant specific activity. Although progesterone was the major steroid formed from pregnenolone, a transient increase in androgen formation with a concomitant decrease in estrogen formation in developing corpora lutea was followed by an increase in estrogen with a decrease in androgen formation in mature corpora lutea. The reciprocal relation between estrogen and androgen formation is associated with the behaviour of theca lutein cells since the cells disappeared at the former and clearly differentiated at the latter stages of corpora lutea. The outer layers consistently produced more 17-hydroxyprogesterone, androgens and estrogens from pregnenolone than the inner layers, while the inner layers converted constantly more androstenedione to estrogens than the outer layers. It is suggested that aromatase activity of granulosa lutein cells in co-existence with theca lutein cells is required by human corpora lutea for fulfillment of the function of estrogen synthesis.
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Takahide M, Kenji N, Satoru T, Yoshio O, Shimpei T. Interrelation between luteal cell types in steroidogenesis in vitro of human corpus luteum. ACTA ACUST UNITED AC 1983. [DOI: 10.1016/0022-4731(83)90016-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Mori T, Fujita Y, Nihnobu K, Bzaki Y, Kubo K, Nishimura T. Steroidogenesis in vitro by human ovarian follicles during the process of atresia. Clin Endocrinol (Oxf) 1982; 16:391-400. [PMID: 7094362 DOI: 10.1111/j.1365-2265.1982.tb00732.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Slices of each of the six antral follicles at different stages of atresia isolated from ovaries of six patients with or without pretreatment with HCG before laparotomy, were incubated with [1-14C] acetate. Incorporation into progestins, androgens and oestrogens was assessed by the reverse dilution technique with recrystallization to constant specific activity. The greatest incorporation into androstenedione without any incorporation into progesterone was commonly observed throughout the morphologically defined three stages of atresia. In the first stage atretic follicles, characterized by coexistence of normally developed thecal cells with degenerating granulosa cells, a minute incorporation into oestradiol was identified. In the second state atretic follicles, showing hyperplasia and hypertrophy of thecal cells without granulosa cells, an increased incorporation into androgens was shown. Treatment with HCG induced similar but much pronounced changes in function and morphology. In the third stage atretic follicles, with subsiding thecal cells, a diminished incorporation into androstenedione was observed with 17-hydroxyprogesterone being the only other steroid formed in this stage. The observed qualitative and quantitative changes of steroidogenesis in vitro may be functional reflections of structural changes during the atretic process.
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Bukovský A, Presl J. Control of ovarian function by the immune system: commentary on the criticisms of Schenzle. Med Hypotheses 1981; 7:1-14. [PMID: 7010091 DOI: 10.1016/0306-9877(81)90016-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Recent hypothesis on the participation of the immune system in the control of ovarian function is supported by new experimental data. Schenzle's oversimplified endocrine explanation of problems of ovarian function control was critically examined. It is questionable whether the neuroendocrine paradigm should not be revised in the light of the modulating role of the immune system in the ovarian function control.
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Schenzle D. Control of ovarian function by the immune system: is this a plausible and necessary hypothesis? Med Hypotheses 1980; 6:815-29. [PMID: 7442587 DOI: 10.1016/0306-9877(80)90006-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A recently presented hypothesis, according to which cyclic selection of a specific number of follicles for ovulation is brought about by immune mechanisms, will be discussed critically. The arguments and conclusions within the framework of this hypothesis are either not convincing or even at variance with well established facts. It is questioned whether there is any need for such a dramatic extension of the commonly accepted concept for neuroendocrine control of ovarian function.
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Acritopoulou S. Progesterone and LH concentrations in ewes after ICI 80996, an analogue of PGF2α, at two different stages of the breeding season. Theriogenology 1979. [DOI: 10.1016/0093-691x(79)90017-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Hillensjö T, Hamberger L, Ahrén K. Effect of androgens on the biosynthesis of estradiol-17beta by isolated periovulatory rat follicles. Mol Cell Endocrinol 1977; 9:183-93. [PMID: 202526 DOI: 10.1016/0303-7207(77)90119-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Erb RE, Sitarz E, Malven PV. Blood plasma and milk prolactin, and effects of sampling technique on composition of milk from suckled ewes. J Dairy Sci 1977; 60:197-203. [PMID: 838924 DOI: 10.3168/jds.s0022-0302(77)83854-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Relations of techniques of sampling milk to its composition and concentrations of prolactin in blood plasma and milk from 59 suckled ewes were compared; Prolactin in milk and blood samples 0 to 2 h (hour 0) after removal of lambs did not differ significantly within autumn or summer, but both were doubled in summer. After the hour 0 sampling (summer only), one side of the udder of each of 12 ewes (group 1) was milked hourly for 4 h, and the opposite side was milked only at 0 and 4 h. Group 2 ewes were milked only at 0 and 4 h and blood was collected from both groups at 0 h and 4 h. Concentrations of prolactin were correlated in pairs of milk or blood samples from the same ewe and in plasma and milk of ewes in group 2 but not in group 1. Prolactin in milk increased between 0 h and 4 h in groups 1 and 2. Although milk lactose and prolactin concentrations differed among hourly samples, their average was similar to that of milk accumulated in the contralateral side for 4 h (group 1). Variations among ewes in progesterone of plasma indicated luteal activity during autumn and none during summer. Prolactin was unchanged in milk stored at -23 C for 30 days. The hour-0 milk-sampling technique was satisfactory to compare among individuals the concentrations of prolactin, total protein, or somatic cells in milk but not percentage fat and lactose, or milk yield due to variable time from last suckling to milking at hour 0.
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Makris A, Ryan KJ. Evidence for interaction between granulosa cells and theca in early progesterone synthesis. ENDOCRINE RESEARCH COMMUNICATIONS 1977; 4:233-46. [PMID: 598339 DOI: 10.1080/07435807709052943] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The temporal characteristics of steroidogenesis in vitro by hamster preovulatory follicles, were compared to granulosa cells and theca incubated separately. Gonadotropin-stimulated intact follicles or recombined granulosa cells and theca synthesized increased amounts of progesterone by 30-120 minutes of incubation. The granulosa cells and theca, when incubated separately, did not begin to accumulate progesterone until 4 to 6 hours. The relatively rapid rise in follicular progesterone synthesis after in vitro gonadotropin stimulation follows the same time course as the rapid rise in vivo of hamster and rat preovulatory progesterone after the gonadotropin surge. The sharp differences in the temporal characteristics of progesterone synthesis between follicles and separated follicular cell types suggest an interaction between granulosa cells and theca in at least one phase of progesterone synthesis.
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Rüsse VI, Stolla R. Einfluß von synthetischem LH-RH auf die Ovarfunktion von Schafen am Ende des Zyklus. Reprod Domest Anim 1976. [DOI: 10.1111/j.1439-0531.1976.tb00308.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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McClellan MC, Dieckman MA, Abel JH, Niswender GD. Luteinizing hormone, progesterone and the morphological development of normal and superovulated corpora lutea in sheep. Cell Tissue Res 1975; 164:291-307. [PMID: 1201606 DOI: 10.1007/bf00223011] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The development of granulosa-lutein cells was studied in 27 normal and 32 superovulated ewes between days 0-4(day 0 began with the preovulatory LH peak in normal animals and the HCG injection in superovulated ewes). The pattern of differentiation was similar in both groups. Following initial hormonal stimulation (0-12 hours after LH or HCG), granulosa cells were approximately 100 mu2 and contained small, pleomorphic nuclei with large amounts of clumped chromatin. Elongate cells lining the basement membrane possessed large, heterogeneous dense bodies, and a well-developed Golgi apparatus. Mitotic figures were observed up to 6 hours prior to ovulation. Sixteen to 20 hours following the LH surge or HCG injection, hypertrophy of granulosa cells was evident. Nuclei contained definitive nucleoli. Blood vessels in the theca interna were abundant and highly dilated. Ovulation occurred approximately 24 hours after the LH peak or HCG injection. Visible signs of luteinization were evident 6-12 hours after ovulation. A slight increase in serum progesterone levels was detected. The second post-ovulatory day was characterized by continuing hypertrophy of granulosa cells and extensive proliferation of smooth endoplasmic reticulum and mitochondria. Nuclei of granulosa cells were larger and possessed extremely large nucleoli. Numerous mitotic figures were apparent within the corpus luteum. Serum progesterone concentrations began increasing at 60-72 hours after hormone stimulation. By the end of the third post-ovulatory day, the corpus luteum consisted of large, pleomorphic, parenchymal cells, interspersed between capillaries and connective tissue elements. Only an occasional mitotic figure was apparent within the corpus luteum at 100 hours. Light microscopic autoradiography of 5, 10, and 15 day corpora lutea taken from ewes pulsed with 3H thymidine at specific times before and after ovulation revealed that granulosa cells did not undergo secondary mitoses following ovulation. In contrast, thecal, mesenchymal and endothelial cells did mitose on day 3.
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Boone WR, Hill JR, Kennedy SW, Henricks DM. Influence of nutrition on reproduction in the ewe with special emphasis on progesterone concentration. Theriogenology 1975; 3:140-51. [PMID: 1165008 DOI: 10.1016/0093-691x(75)90195-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Abstract
The morphologic development of rabbit ovarian follicles was studied by means of light and electron microscopy 0, 2, 4, 6, 8, and 10 hours after copulation. The progressive changes at the apex of the follicle included extensive edema, hyperemia, and rupture of blood vessels, and then rupture of the follicular wall. Ovulation occurred when the cohesive forces in the cellular layers of the follicular apex became less than the physical forces within the follicle. Most of the morphologic changes in the follicle as it approached ovulation could be related to the effects of locally produced estrogens.
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Symons AM. Radioimmunoassays and ruminant endocrinology. Proc Nutr Soc 1974; 33:183-90. [PMID: 4456382 DOI: 10.1079/pns19740032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Bjersing L, Cajander S. Ovulation and the mechanism of follicle rupture. I. Light microscopic changes in rabbit ovarian follicles prior to induced ovulation. Cell Tissue Res 1974; 149:287-300. [PMID: 4609613 DOI: 10.1007/bf00226764] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Bjersing L, Frankendal B, Angström T. Studies on a feminizing ovarian mesenchymoma (granulosa cell tumor). I. Aspiration biopsy cytology, histology, and ultrastructure. Cancer 1973; 32:1360-9. [PMID: 4757927 DOI: 10.1002/1097-0142(197312)32:6<1360::aid-cncr2820320613>3.0.co;2-s] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Edwards RG, Steptoe PC, Abraham GE, Walters E, Purdy JM, Fotherby K. Steroid assays and preovulatory follicular development in human ovaries primed with gonadotrophins. Lancet 1972; 2:611-5. [PMID: 4116773 DOI: 10.1016/s0140-6736(72)93013-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Armato U, Nussdorfer GG. Tissue culture of rat adult decapsulated adrenal glands. A methodological, ultrastructural and morphometric investigation. ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1972; 135:245-73. [PMID: 4345190 DOI: 10.1007/bf00315129] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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