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Estrous cycle stage-independent treatment of PMSG and hCG can induce superovulation in adult Wistar-Imamichi rats.
Abstract: The estrous cycle influence on the number of ovulated eggs after injection of pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) was investigated in 12, 18, and 24 weeks old adult female Wistar-Imamichi (WI) rats. PMSG (150 IU/kg) was injected at metestrus, diestrus, proestrus, or estrus, followed by hCG (75 IU/kg) 55 h later. Ovulation was induced at all ages and stages of the estrous cycle. The number of ovulated eggs was not affected by stage for similarly aged rats, however, the number of ovulated eggs obtained after treatment decreased with age. These results demonstrate that the PMSG/hCG treatment can induce ovulation at any stage of estrous cycle in WI rats and efficient superovulation at 12 weeks of age.
Publication Date: 2005-05-18 PubMed ID: 15897629DOI: 10.1538/expanim.54.185Google Scholar: Lookup The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research involves examining the effect of the estrous cycle on the number of eggs produced after injecting adult female Wistar-Imamichi rats with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). The researchers found that the stage of the estrous cycle doesn’t affect egg production, but the rats’ aging reduces the number of eggs produced.
Objective
The main objective of this research was to explore if the stage of the estrous cycle has any influence on the number of eggs ovulated in female rats after being treated with PMSG and hCG. Simultaneously, it aimed to study if aging has any effect on the successful induction of ovulation.
Methods
- The experiment was conducted on Wistar-Imamichi (WI) rats that were 12, 18, and 24 weeks old. The choice of these timeframes aimed to ensure a substantial difference in the rats’ age to understand the effect of aging on ovulation.
- Each rat was treated with PMSG (150 IU/kg) and was injected at different stages – metestrus, diestrus, proestrus, or estrus.
- 55 hours after PMSG, the rats were injected with hCG (75 IU/kg).
Results
- After the treatment, ovulation occurred in rats irrespective of their ages and stages of the estrous cycle. This observation indicates that the treatment regime could induce ovulation at any estrous cycle stage.
- Error notwithstanding/Apart from intrinsic research limitations, the stage of the estrous cycle did not have any observable effect on the number of eggs ovulated. Regardless of the stage, rats of similar ages produced a comparable number of eggs.
- Contrarily/A contrastingly, researchers noticed that as the rats aged, they produced lesser eggs after being treated – the number of eggs ovulated reduced from 12 weeks to 24 weeks of age.
Conclusion
This research successfully demonstrated that the PMSG and hCG regimen can induce ovulation at any estrous stage in WI rats. However, this efficient superovulation was most noticeable when given to 12 weeks old rats, with declining efficiency observed as the rats aged.
Cite This Article
APA
Kon H, Tohei A, Hokao R, Shinoda M.
(2005).
Estrous cycle stage-independent treatment of PMSG and hCG can induce superovulation in adult Wistar-Imamichi rats.
Exp Anim, 54(2), 185-187.
https://doi.org/10.1538/expanim.54.185 Publication
Researcher Affiliations
- Laboratory Animal Research Center, Dokkyo University School of Medicine, Tochigi, Japan.
MeSH Terms
- Aging / physiology
- Animals
- Chorionic Gonadotropin / administration & dosage
- Chorionic Gonadotropin / pharmacology
- Estrous Cycle / physiology
- Female
- Gonadotropins, Equine / administration & dosage
- Gonadotropins, Equine / pharmacology
- Injections, Intraperitoneal
- Rats
- Rats, Wistar
- Stimulation, Chemical
- Superovulation / drug effects
Citations
This article has been cited 6 times.- Mao Y, Wang M, Xiong Y, Wen X, Zhang M, Ma L, Zhang Y. MELTF Might Regulate Ferroptosis, Pyroptosis, and Autophagy in Platelet-Rich Plasma-Mediated Endometrial Epithelium Regeneration. Reprod Sci 2023 May;30(5):1506-1520.
- Jang HY, Myoung SM, Choe JM, Kim T, Cheon YP, Kim YM, Park H. Effects of Autologous Platelet-Rich Plasma on Regeneration of Damaged Endometrium in Female Rats. Yonsei Med J 2017 Nov;58(6):1195-1203.
- Taketsuru H, Kaneko T. In vitro maturation of immature rat oocytes under simple culture conditions and subsequent developmental ability. J Reprod Dev 2016 Oct 18;62(5):521-526.
- Kon H, Hokao R, Shinoda M. Fertilizability of Superovulated Eggs by Estrous Stage-independent PMSG/hCG Treatment in Adult Wistar-Imamichi Rats. Exp Anim 2014;63(2):175-82.
- Filipiak WE, Saunders TL. Advances in transgenic rat production. Transgenic Res 2006 Dec;15(6):673-86.
- Wang F, Wang W, Zhang S, Wang Y, Zhang R, An L, Tian J, Xi G. Ovulatory Signal-Driven H3K4me3 and H3K27ac Remodeling in Mural Granulosa Cells Orchestrates Oocyte Maturation and Ovulation. Cells 2025 Dec 24;15(1).
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