scholarly journals Effect of thymectomy on the female reproductive cycle in neonatal guinea pigs

2020 ◽  
Vol 47 (1) ◽  
pp. 12-19
Author(s):  
P. Murali ◽  
J. Radhika ◽  
D. Alwin
Keyword(s):  
Reproductive Cycle ◽  
Guinea Pigs ◽  
Neonatal Period ◽  
Reproductive Function ◽  
Normal Female ◽  
Vaginal Opening ◽  
Estrus Cycle ◽  
Reproductive Axis ◽  
17Β Estradiol ◽  
Estradiol Levels

Objective: The appropriate function of the hypothalamic-pituitary-gonadal axis is essential for maintaining proper reproductive function. In female mammals, the hypothalamic-pituitary-gonadal axis regulates reproductive changes that take place in the estrus cycle and are necessary for successful reproduction. This study was conducted to investigate the effect of thymectomy on the estrus cycle in neonatally thymectomized guinea pigs.Methods: In this study, 12 female guinea pigs, six thymectomized and six sham-operated, were studied. The effects of neonatal thymectomy at 5–7 days of age on parameters of the reproductive axis were examined in female guinea pigs. Gonadotropin and 17β-estradiol levels were assessed at regular intervals (days 0, 3, 6, 9, 12, and 15) of the estrus cycle, and the time of vaginal opening in the thymectomized and shamoperated guinea pigs was determined.Results: Significant reductions in gonadotropins and 17β-estradiol levels during estrus cycle were found in neonatally thymectomized female guinea pigs compared to sham-operated guinea pigs.Conclusion: The results of this study underscore the importance of the thymus in the neonatal period for normal female reproductive function.

scholarly journals Effect of thymectomy on the female reproductive cycle in prepubertal and pubertal female guinea pigs

2020 ◽  
Vol 11 (SPL4) ◽  
pp. 1155-1161
Author(s):  
Murali Punniakotti ◽  
Sundarapandian Subramanian ◽  
Pratheepa sivasankari
Keyword(s):  
Reproductive Cycle ◽  
Guinea Pigs ◽  
Reproductive Function ◽  
Oestrous Cycle ◽  
Proper Function ◽  
Estrus Cycle ◽  
Study Results ◽  
Significant Difference ◽  
17Β Estradiol ◽  
Estradiol Levels

The proper function of the hypothalamic-pituitary-ovarian axis is essential for maintaining proper female reproductive function. In female mammals, the hypothalamic-pituitary-ovarian axis regulates reproductive changes that take place in the estrus cycle and are necessary for successful reproduction. This study aimed to investigate the influence of thymus gland on the female reproductive function in different stages of life. This present study was conducted to investigate the effect of thymectomy on the estrus cycle in prepubertal (5th week) and pubertal (7th week) thymectomized guinea pigs. In this study, 24 female guinea pigs, six thymectomized and six sham-operated in each group were studied. Gonadotropin and 17β-estradiol levels were assessed at regular intervals (days 0, 3, 6, 9, 12 and 15) of the estrus cycle, and the length of the oestrous cycle in the thymectomized and sham-operated guinea pigs was determined. The results showed no significant difference in gonadotropin and 17β-estradiol were detected in thymectomized versus sham-operated guinea pigs at any intervals of the oestrous cycle. Thymectomy did not affect the length of the oestrous cycle of females. In conclusion, the present study results suggested that the presence of thymus during prepubertal and pubertal life was not necessary to regulate the oestrous cycle of female guinea pigs.

Plasma vitellogenin and 17β-estradiol levels during the annual reproductive cycle of Podarcis s. sicula Raf

1991 ◽  
Vol 84 (3) ◽  
pp. 337-343 ◽  
Author(s):  
O. Carnevali ◽  
G. Mosconi ◽  
F. Angelini ◽  
E. Limatola ◽  
G. Ciarcia ◽  
...  
Keyword(s):  
Reproductive Cycle ◽  
Annual Reproductive Cycle ◽  
17Β Estradiol ◽  
Estradiol Levels

scholarly journals The use of GnRH agonist for supression of cats reproductive function

2017 ◽  
Vol 19 (73) ◽  
pp. 25-27
Author(s):  
A.I. Vasetska ◽  
A.A. Mass
Keyword(s):  
Reproductive Cycle ◽  
Gnrh Agonist ◽  
Reproductive System ◽  
Average Duration ◽  
Reproductive Function ◽  
Control Group ◽  
Estrus Cycle ◽  
The Third ◽  
One Year ◽  
Subcutaneous Implant

The article presents the results concerning the duration of GnRH agonist deslorelin «Suprelorin» 4.7 mg using in cats prepubertal and pubertal age. Experiments conducted on pedigree and non-pedigree cats and lasting for 2.5 years. For research was formed three groups (n = 10), age from 3 months to 3 years. The first group was the control animals, they flowed naturally estrus cycle, they received any drugs and have no contact with male. The estrus cycle of the control group of animals observed an average six times within one year, three times in spring and autumn, which is the norm for this type of animal. For 30 months (2.5 years) observation cats from the control group showed excitement stage of estrus cycle an average 15 times. Animals from the second group, age 3–6 months, which has not have the first estrus (prepubertal) was placed subcutaneous implant «Suprelorin» 4.7 mg. In the third group were cats from 7 months to 3 years which have experienced one or more estrus cycles (pubertal). The animals were implanted implant «Suprelorin» 4.7 mg immediately after the last estrus. In the second group of animals (prepubertal), excitement stage of reproductive cycle manifested through 480–1567 days after implant implanted and the average duration of the reproductive cycle was 920 days (30 months). A few cats from this group were found changes in the reproductive system such as: uneven structure of the endometrium, reducing the size of the ovaries, ovarian cysts after ovariohysterectomy. Cats from the third group (pubertal) excitement stage of reproductive cycle manifested after 120 to 730 days after implanted the GnRH implant and the average duration of the reproductive cycle was 379 days (approximately 13 months). A few cats from this group, after ovariohysterectomy, observed changes in the reproductive system such as: endometrial hyperplasia, uneven structure and porosity consistency endometrial, ovarian cyst.

scholarly journals An Antagonistic Peptide of Gpr1 Ameliorates LPS-Induced Depression through the Hypothalamic-Pituitary-Ovarian Axis

Biomolecules ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 857
Author(s):  
Rongrong Li ◽  
Chiyuan Ma ◽  
Yue Xiong ◽  
Huashan Zhao ◽  
Yali Yang ◽  
...  
Keyword(s):  
Ovarian Function ◽  
Preference Test ◽  
Antidepressant Effect ◽  
Normal Female ◽  
Reproductive Axis ◽  
Immobility Time ◽  
Potential Therapeutic Application ◽  
Antagonistic Peptide ◽  
Sucrose Preference Test ◽  
G Protein Coupled

Depression affects the reproductive axis at the hypothalamus and pituitary levels, which has a significant impact on female fertility. It has been reported that G protein-coupled receptor 1 (Gpr1) mRNA is expressed in both the hypothalamus and ovaries. However, it is unclear whether there is a relationship between Gpr1 and depression, and its role in ovarian function is unknown. Here, the expression of Gpr1 was recorded in the hypothalamus of normal female mice, and co-localized with gonadotrophin-releasing hormone (GnRH) and corticotropin-releasing factor (CRF). We established a depression mouse model to evaluate the antidepressant effect of G5, an antagonistic peptide of Gpr1. The results show that an intraperitoneal injection of G5 improves depressant–like behaviors remarkably, including increased sucrose intake in the sucrose preference test and decreased immobility time in the forced swimming tests. Moreover, G5 treatment increased the release of reproductive hormone and the expression of ovarian gene caused by depression. Together, our findings reveal a link between depression and reproductive diseases through Gpr1 signaling, and suggest antagonistic peptide of Gpr1 as a potential therapeutic application for hormone-modulated depression in women.

scholarly journals Proliferative and Apoptotic Pathways in the Testis of Quail Coturnix coturnix during the Seasonal Reproductive Cycle

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1729
Author(s):  
Sara Falvo ◽  
Luigi Rosati ◽  
Maria Maddalena Di Fiore ◽  
Federica Di Giacomo Russo ◽  
Gabriella Chieffi Baccari ◽  
...  
Keyword(s):  
Reproductive Cycle ◽  
Second Messengers ◽  
Reproductive Period ◽  
Annual Reproductive Cycle ◽  
Coturnix Coturnix ◽  
Immunohistochemistry Analysis ◽  
17Β Estradiol ◽  
Apoptotic Pathways ◽  
Camp And Cgmp ◽  
Activation Phase

The quail Coturnix coturnix is a seasonal breeding species, with the annual reproductive cycle of its testes comprising an activation phase and a regression phase. Our previous results have proven that the testicular levels of both 17β-estradiol (E2) and androgens are higher during the reproductive period compared to the non-reproductive period, which led us to hypothesize that estrogens and androgens may act synergistically to initiate spermatogenesis. The present study was, therefore, aimed to investigate the estrogen responsive system in quail testis in relation to the reproduction seasonality, with a focus on the molecular pathways elicited in both active and regressive quail testes. Western blotting and immunohistochemistry analysis revealed that the expression of ERα, which is the predominant form of estrogen receptors in quail testis, was correlated with E2 concentration, suggesting that increased levels of E2-induced ERα could play a key role in the resumption of spermatogenesis during the reproductive period, when both PCNA and SYCP3, the mitotic and meiotic markers, respectively, were also increased. In the reproductive period we also found the activation of the ERK1/2 and Akt-1 kinase pathways and an increase in second messengers cAMP and cGMP levels. In the non-reproductive phase, when the E2/ERα levels were low, the inactivation of ERK1/2 and Akt-1 pathways favored apoptotic events due to an increase in the levels of Bax and cytochrome C, with a consequent regression of the gonad.

Plasma 17β-estradiol levels in the chick embryo

1981 ◽  
Vol 44 (1) ◽  
pp. 37-43 ◽  
Author(s):  
James E. Woods ◽  
Dianne M. Brazzill
Keyword(s):  
Chick Embryo ◽  
17Β Estradiol ◽  
Estradiol Levels

Peritraumatic 17β-estradiol levels influence chronic posttraumatic pain outcomes

Pain ◽  
2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Sarah D. Linnstaedt ◽  
Matthew C. Mauck ◽  
Esther YeEun Son ◽  
Andrew S. Tungate ◽  
Yue Pan ◽  
...  
Keyword(s):  
Pain Outcomes ◽  
17Β Estradiol ◽  
Estradiol Levels

On a Peculiar Type of Intersexuality in the Guinea-Pig

1927 ◽  
Vol 4 (3) ◽  
pp. 227-244
Author(s):  
ALEXANDER LIPSCHUTZ
Keyword(s):  
Guinea Pig ◽  
Guinea Pigs ◽  
Mammary Glands ◽  
The Other ◽  
Normal Male ◽  
Normal Female ◽  
Sexual Hormones ◽  
Testicular Transplantation ◽  
Hereditary Nature ◽  
External Genital Organs

An abnormal condition of the external genital organs in 16 otherwise normal female guinea-pigs is described. They possessed an hypertrophied penis-like clitoris and horny styles similar to those in the intromittent sac of the normal male penis. The abnormalities are often asymmetrical, the clitoris and the horny style on one side being more developed than on the other. They may even be absent on one side. It is suggested that the malformation is a peculiar type of "partial somatic intersexuality," the external genital organs resembling those in the male guinea-pig. The condition is identical with that described in the castrated female guinea-pig experimentally masculinised by testicular transplantation. There was no indication of the ovaries producing simultaneously female and male sexual hormones: (a) The ovaries were histologically normal. (b) The ovaries when engrafted into castrated males produced the typical female hormonic effect on the mammary glands and had no influence on the penis or on the horny styles. (c) The clitoris and the horny styles of the intersexual females were not affected by removal of the ovaries, whereas in the male removal of the testes caused a pronounced regression of the horny styles even in fully grown animals. (d) The horny styles when cut regenerated even after removal of the ovaries; there is never a regeneration in the castrated male, but only in the normal male. The question is discussed whether the described type of intersexuality might be a case of "successive hormonic intersexuality," both kinds of sexual hormones having been produced simultaneously for a certain time whereas at a later stage only female hormones were secreted. The hypertrophied clitoris and the horny styles would then be considered as "fixed" sex characters persisting after the disappearance of the male sexual hormones. The problem of fixation of sex characters by sexual hormones is considered on experimental lines. The facts observed are rather against the suggestion that the intersexuality described is a case of successive hormonic intersexuality. Other possibilities of explaining the morphogenetic basis of this peculiar type of intersexuality are also discussed. The intersexuality described is of an hereditary nature.

Expression of NMS and NMU2R in the pig reproductive axis during the estrus cycle and the effect of NMS on the reproductive axis in vitro

Peptides ◽  
2009 ◽  
Vol 30 (12) ◽  
pp. 2206-2212 ◽  
Author(s):  
Guihong Yang ◽  
Juan Su ◽  
Xun Li ◽  
Yuan Yao ◽  
Zhihai Lei ◽  
...  
Keyword(s):  
Estrus Cycle ◽  
Reproductive Axis

scholarly journals Comparative effects of testosterone propionate, oestradiol benzoate, ICI 182,780, tamoxifen and raloxifene on hypothalamic differentiation in the female rat

2002 ◽  
Vol 172 (3) ◽  
pp. 441-448 ◽  
Author(s):  
L Pinilla ◽  
ML Barreiro ◽  
LC Gonzalez ◽  
M Tena-Sempere ◽  
E Aguilar
Keyword(s):  
Positive Feedback ◽  
Testosterone Propionate ◽  
Reproductive Function ◽  
Female Rats ◽  
Normal Brain ◽  
Female Rat ◽  
Vaginal Opening ◽  
Ici 182,780 ◽  
Oestradiol Benzoate ◽  
Normal Differentiation

Hypothalamic differentiation in the female rat during the neonatal period is critically dependent on the steroid milieu, as permanent changes in reproductive function are observed after administration of oestradiol and testosterone during such a critical stage. Selective oestrogen modulators (SERMs) constitute a family of drugs that, depending on the tissue, are able to exert oestrogenic or antioestrogenic actions. The present experiments were conducted to analyse whether the SERMs, tamoxifen and raloxifene, can cause oestrogenic actions during the hypothalamic differentiation period. Postnatal female rats were injected between days 1 and 5 with 100 microg/day tamoxifen, raloxifene or ICI 182,780 (a pure antioestrogen). Other groups of animals were injected on day 1 of age with 100 microg oestradiol benzoate (OeB) or 1.25 mg testosterone propionate (TP) alone or in combination with raloxifene (500 microg/day between days 1 and 5). In all experimental groups, the age, body weight and concentrations of serum gonadotrophins at vaginal opening were recorded, whereas vaginal cyclicity and the negative and positive feedback between oestradiol and LH were monitored in adulthood. The results obtained confirmed the ability of high doses of OeB or TP to alter the normal differentiation of the brain permanently. They also reinforced the hypothesis that oestrogens are also necessary for normal brain differentiation in female rats because administration of a pure antioestrogen, such as ICI 182,780 permanently altered the function of the reproductive axis. In addition, our data provided evidence for different actions of the two SERMs under analysis (raloxifene and tamoxifen) upon peripheral targets, as raloxifene advanced vaginal opening whereas tamoxifen did not. In contrast, their actions on brain differentiation appeared similar and analogous to those obtained after neonatal administration of oestradiol, as evidenced by vaginal acyclicity, ovarian atrophy, sterility and abolition of negative and positive feedback between oestradiol and LH, thus suggesting an oestrogenic action of these SERMs on hypothalamic differentiation. Moreover, the oestrogenic activity of raloxifene was supported by its inability to block the effects of OeB and TP administered neonatally. In conclusion, the present results indicated that the SERMs, tamoxifen and raloxifene, exert an oestrogen-like effect upon hypothalamic differentiation of the neonatal female rat.

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