Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Biological and anatomical evidence for kisspeptin regulation of the hypothalamic-pituitary-gonadal axis of estrous horse mares.
Abstract: The purpose of the present study was to evaluate the effects of kisspeptin (KiSS) on LH and FSH secretion in the seasonally estrous mare and to examine the distribution and connectivity of GnRH and KiSS neurons in the equine preoptic area (POA) and hypothalamus. The diestrous mare has a threshold serum gonadotropin response to iv rodent KiSS decapeptide (rKP-10) administration between 1.0 and 500 microg. Administration of 500 microg and 1.0 mg rKP-10 elicited peak, mean, and area under the curve LH and FSH responses indistinguishable to that of 25 microg GnRH iv, although a single iv injection of 1.0 mg rKP-10 was insufficient to induce ovulation in the estrous mare. GnRH and KiSS-immunoreactive (ir) cells were identified in the POA and hypothalamus of the diestrous mare. In addition, KiSS-ir fibers were identified in close association with 33.7% of GnRH-ir soma, suggesting a direct action of KiSS on GnRH neurons in the mare. In conclusion, we are the first to reveal a physiological role for KiSS in the diestrous mare with direct anatomic evidence by demonstrating a threshold-like gonadotropin response to KiSS administration and characterizing KiSS and GnRH-ir in the POA and hypothalamus of the diestrous horse mare.
Publication Date: 2009-02-19 PubMed ID: 19228887DOI: 10.1210/en.2008-1698Google 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
- Research Support
- Non-U.S. Gov't
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.
This research focused on the role of a protein called kisspeptin (KiSS) in regulating reproductive hormones in female horses. The researchers discovered that this protein appears to directly influence the cells responsible for producing these hormones, and demonstrated a certain dose range at which its administration triggers a response.
Study Objectives and Methodology
- The study aimed to understand how kisspeptin (KiSS) affects the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which are critical for reproduction in female horses that are in their diestrus phase (non-reproductive period).
- It also sought to investigate the network and distribution of GnRH (gonadotropin-releasing hormone) and KiSS neurons in the preoptic area (POA) and hypothalamus (key brain regions in hormone regulation) of the mare.
- To achieve these aims, the researchers administered intravenous injections of a version of the KiSS protein derived from rodents (rKP-10) at different doses, and monitored the resultant LH and FSH responses.
- They also examined GnRH and KiSS activity in the POA and hypothalamus in the diestrous mare.
Key Findings
- The study found that the administration of rKP-10 causes a response in the production of LH and FSH within a certain dose range.
- A further increase in the dose of rKP-10 caused a peak in LH and FSH levels equivalent to that of an injection of GnRH. However, even the highest dosage of rKP-10 tested was not enough to trigger ovulation in the mare.
- The research also discovered that KiSS and GnRH-reactive cells are present in the POA and hypothalamus during the diestrus phase.
- Moreover, KiSS fibers were identified in close proximity with approximately a third of GnRH-producing cells, suggesting a possible direct interaction between KiSS and GnRH neurons.
Conclusions and Implications
- The findings of this study suggest that KiSS plays an important role in the endocrine regulation of the reproductive cycle in female horses during their diestrus phase.
- The research also provides the first anatomical evidence of a direct interaction between KiSS and GnRH neurons in the mare, affirming a potential direct role of KiSS in the reproductive hormone regulation.
- These insights could have significant implications in the understanding and potential treatment of reproduction-related disorders in horses and possibly other mammals, given the common role of these hormones in sexual maturity and reproduction.
Cite This Article
APA
Magee C, Foradori CD, Bruemmer JE, Arreguin-Arevalo JA, McCue PM, Handa RJ, Squires EL, Clay CM.
(2009).
Biological and anatomical evidence for kisspeptin regulation of the hypothalamic-pituitary-gonadal axis of estrous horse mares.
Endocrinology, 150(6), 2813-2821.
https://doi.org/10.1210/en.2008-1698 Publication
Researcher Affiliations
- Department of Biomedical Sciences, Animal Reproduction and Biotechnology Laboratory, Colorado State University, Fort Collins, Colorado 80523, USA.
MeSH Terms
- Animals
- Estrous Cycle / drug effects
- Estrous Cycle / physiology
- Female
- Follicle Stimulating Hormone / blood
- Gonadotropin-Releasing Hormone / metabolism
- Horses / physiology
- Hypothalamo-Hypophyseal System / drug effects
- Hypothalamo-Hypophyseal System / physiology
- Hypothalamus / cytology
- Hypothalamus / metabolism
- Injections, Intravenous
- Kisspeptins
- Luteinizing Hormone / blood
- Models, Animal
- Neurons / metabolism
- Oligopeptides / administration & dosage
- Oligopeptides / physiology
- Ovary / drug effects
- Ovary / physiology
- Ovulation / drug effects
- Preoptic Area / cytology
- Preoptic Area / metabolism
- Reproduction / physiology
- Tumor Suppressor Proteins / metabolism
Citations
This article has been cited 12 times.- Harlow K, Griesgraber MJ, Seman AD, Shuping SL, Sommer JR, Griffith EH, Hileman SM, Nestor CC. The impact of undernutrition on KNDy (kisspeptin/neurokinin B/dynorphin) neurons in female lambs. J Neuroendocrinol 2022 Jun;34(6):e13135.
- Merkley CM, Renwick AN, Shuping SL, Harlow K, Sommer JR, Nestor CC. Undernutrition reduces kisspeptin and neurokinin B expression in castrated male sheep. Reprod Fertil 2020 Jul;1(1):1-13.
- Zhao S, Guo Z, Xiang W, Wang P. The neuroendocrine pathways and mechanisms for the control of the reproduction in female pigs. Anim Reprod 2021;18(4):e20210063.
- Okada CTC, Kaps M, Perez Quesada J, Gautier C, Aurich J, Aurich C. Diestrous Ovulations in Pregnant Mares as a Response to Low Early Postovulatory Progestogen Concentration. Animals (Basel) 2020 Nov 30;10(12).
- Tanco VM, Whitlock BK, Jones MA, Wilborn RR, Brandebourg TD, Foradori CD. Distribution and regulation of gonadotropin-releasing hormone, kisspeptin, RF-amide related peptide-3, and dynorphin in the bovine hypothalamus. PeerJ 2016;4:e1833.
- Lehman MN, Hileman SM, Goodman RL. Neuroanatomy of the kisspeptin signaling system in mammals: comparative and developmental aspects. Adv Exp Med Biol 2013;784:27-62.
- Kaur KK, Allahbadia G, Singh M. Kisspeptins in human reproduction-future therapeutic potential. J Assist Reprod Genet 2012 Oct;29(10):999-1011.
- Hrabovszky E, Molnár CS, Sipos MT, Vida B, Ciofi P, Borsay BA, Sarkadi L, Herczeg L, Bloom SR, Ghatei MA, Dhillo WS, Kalló I, Liposits Z. Sexual dimorphism of kisspeptin and neurokinin B immunoreactive neurons in the infundibular nucleus of aged men and women. Front Endocrinol (Lausanne) 2011;2:80.
- Kirby HR, Maguire JJ, Colledge WH, Davenport AP. International Union of Basic and Clinical Pharmacology. LXXVII. Kisspeptin receptor nomenclature, distribution, and function. Pharmacol Rev 2010 Dec;62(4):565-78.
- Lehman MN, Merkley CM, Coolen LM, Goodman RL. Anatomy of the kisspeptin neural network in mammals. Brain Res 2010 Dec 10;1364:90-102.
- Oakley AE, Clifton DK, Steiner RA. Kisspeptin signaling in the brain. Endocr Rev 2009 Oct;30(6):713-43.
- Maddeh T, Souid I, Snoussi H, Hammami R, Kurnaz M, Altınkök M. Impact of a 25-minute nap on cognitive variables and reactive management of disruptive behaviour in trainee secondary school physical education teachers. BMC Psychol 2025 Dec 16;13(1):1362.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
