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INTRODUCTION: Kisspeptin (KP) is involved in multiple hypothalamic regulatory processes such as estrogenic feedback to GnRH neurons via synaptic connections. We have reported previously that GnRH neurons send endocannabinoid retrograde signals to regulate their GABAergic input. KP‑producing neurons co‑synthesize GABA or glutamate both in the preoptic (POA) and arcuate (ARC) subpopulations. Moreover, we found the cannabinoid receptor type one (CB1) mRNA in these areas. However, it is unknown whether any subpopulation of KP neurons is under the influence of endocannabinoids. AIM(S): 1) To identify the GABAergic and glutamatergic subpopulations of KP neurons in female mice. 2) To determinate whether CB1 transcripts can be detected in any of the subpopulation of POA or ARC KP neurons. METHOD(S): The transcripts of KP, CB1, and the GABAergic and glutamatergic marker proteins, i.e., vesicular inhibitory amino acid transporter (VIAAT), and vesicular glutamate transporter-2 (VGLUT2) have been detected by RNAscope in situ hybridization technique. The signal was analyzed by confocal microscopy and quantified using our in‑house developed program. RESULTS: We found a significantly increased KP mRNA expression in the POA of ovariectomised mice after estradiol replacement. CB1 mRNAs were found in GABAergic and glutamatergic KP neurons of the POA and ARC. About 67% (AVPV) – 43% (ARC) of the GABAergic KP neurons expressed CB1 mRNA in the OVX+OIL mice, and about 31% (AVPV) – 36% (ARC) of the GABAergic KP neurons expressed CB1 mRNA in the OVX+EB mice. Concerning the glutamatergic KP neurons, about 19% (AVPV) ‑14% (ARC) expressed CB1 mRNA in the OVX- +OIL mice and about 24% (AVPV) – 43% (ARC) of them expressed CB1 mRNA in the OVX+EB mice. CONCLUSIONS: The hormonal status of mice influences the number of KP neurons expressing CB1 and endocannabinoids likely regulate the electrical activity of different KP subpopulations involved in the regulation of various hypothalamic processes.