title: Molecular properties of Kiss1 neurons in the arcuate nucleus of the mouse.
abstract: Neurons that produce kisspeptin play a critical role in reproduction. However, understanding the molecular physiology of kisspeptin neurons has been limited by the lack of an in vivo marker for those cells. Here, we report the development of a Kiss1-CreGFP knockin mouse, wherein the endogenous Kiss1 promoter directs the expression of a Cre recombinase-enhanced green fluorescent protein (GFP) fusion protein. The pattern of GFP expression in the brain of the knockin recapitulates what has been described earlier for Kiss1 in the male and female mouse, with prominent expression in the arcuate nucleus (ARC) (in both sexes) and the anteroventral periventricular nucleus (in females). Single-cell RT-PCR showed that the Kiss1 transcript is expressed in 100% of GFP-labeled cells, and the CreGFP transcript was regulated by estradiol in the same manner as the Kiss1 gene (i.e. inhibited in the ARC and induced in the anteroventral periventricular nucleus). We used this mouse to evaluate the biophysical properties of kisspeptin (Kiss1) neurons in the ARC of the female mouse. GFP-expressing Kiss1 neurons were identified in hypothalamic slice preparations of the ARC and patch clamped. Whole-cell (and loose attached) recordings revealed that Kiss1 neurons exhibit spontaneous activity and expressed both h- (pacemaker) and T-type calcium currents, and hyperpolarization-activated cyclic nucleotide-regulated 1-4 and CaV3.1 channel subtypes (measured by single cell RT-PCR), respectively. N-methyl-D-aspartate induced bursting activity, characterized by depolarizing/hyperpolarizing oscillations. Therefore, Kiss1 neurons in the ARC share molecular and electrophysiological properties of other CNS pacemaker neurons.
authors.affiliation: Department of Obstetrics and Gynecology, Howard Hughes Medical Institute, University of Washington, Seattle, Washington 98195-7290, USA.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Gottsch
authors.forename: Simina M
authors.initials: SM
authors.lastname: Popa
authors.forename: Janessa K
authors.initials: JK
authors.lastname: Lawhorn
authors.forename: Jian
authors.initials: J
authors.lastname: Qiu
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Tonsfeldt
authors.forename: Martha A
authors.initials: MA
authors.lastname: Bosch
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Kelly
authors.forename: Oline K
authors.initials: OK
authors.lastname: Rønnekleiv
authors.forename: Elisenda
authors.initials: E
authors.lastname: Sanz
authors.forename: G Stanley
authors.initials: GS
authors.lastname: McKnight
authors.forename: Donald K
authors.initials: DK
authors.lastname: Clifton
authors.forename: Richard D
authors.initials: RD
authors.lastname: Palmiter
authors.forename: Robert A
authors.initials: RA
authors.lastname: Steiner
mesh_terms: D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D059648:Kisspeptins / Q000378:metabolism*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D009919:Orchiectomy; D010052:Ovariectomy; D012098:Reproduction / Q000187:drug effects / Q000502:physiology*
chemical_list: C491407:Kiss1 protein, mouse; D059648:Kisspeptins; D004958:Estradiol