1. Kisspeptin Neurones do not Directly Signal to RFRP‐3 Neurones but RFRP‐3 may Directly Modulate a Subset of Hypothalamic Kisspeptin Cells in Mice
- Author
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Poling, MC, Quennell, JH, Anderson, GM, and Kauffman, AS
- Subjects
Biomedical and Clinical Sciences ,Neurosciences ,Clinical Sciences ,Contraception/Reproduction ,Underpinning research ,1.1 Normal biological development and functioning ,Animals ,Female ,Hypothalamus ,In Situ Hybridization ,Kisspeptins ,Male ,Mice ,Mice ,Inbred C57BL ,Neurons ,Neuropeptides ,Receptors ,G-Protein-Coupled ,Signal Transduction ,RFRP-3 ,Kiss1r ,Gpr74 ,hypothalamus ,neurokinin B ,kisspeptin ,Kiss1 ,Gpr147 ,Gpr54 ,reproduction ,Tacr3 ,GnIH ,Tac2 ,Endocrinology & Metabolism ,Clinical sciences - Abstract
The neuropeptides kisspeptin (encoded by Kiss1) and RFamide-related peptide-3 (also known as GnIH; encoded by Rfrp) are potent stimulators and inhibitors, respectively, of reproduction. Whether kisspeptin or RFRP-3 might act directly on each other's neuronal populations to indirectly modulate reproductive status is unknown. To examine possible interconnectivity of the kisspeptin and RFRP-3 systems, we performed double-label in situ hybridisation (ISH) for the RFRP-3 receptors, Gpr147 and Gpr74, in hypothalamic Kiss1 neurones of adult male and female mice, as well as double-label ISH for the kisspeptin receptor, Kiss1r, in Rfrp-expressing neurones of the hypothalamic dorsal-medial nucleus (DMN). Only a very small proportion (5-10%) of Kiss1 neurones of the anteroventral periventricular region expressed Gpr147 or Gpr74 in either sex, whereas higher co-expression (approximately 25%) existed in Kiss1 neurones in the arcuate nucleus. Thus, RFRP-3 could signal to a small, primarily arcuate, subset of Kiss1 neurones, a conclusion supported by the finding of approximately 35% of arcuate kisspeptin cells receiving RFRP-3-immunoreactive fibre contacts. By contrast to the former situation, no Rfrp neurones co-expressed Kiss1r in either sex, and Tacr3, the receptor for neurokinin B (NKB; a neuropeptide co-expressed with arcuate kisspeptin neurones) was found in
- Published
- 2013