Kisspeptins, peptide products of the Kiss1 gene, are critical players in the reproductive function, particularly as major upstream neuroendocrine regulators of the Hypothalamic-Pituitary-Gonadal (HPG) axis. Kisspeptins are crucial for gonadotropin releasing hormone (GnRH) secretion, and subsequently for puberty onset and reproductive function. In mice, two distinct populations of Kiss1 expressing neurons are predominant in areas of the hypothalamus implicated in the neuroendocrine regulation of gonadotropin secretion: the arcuate nucleus (ARC) and the anteroventral periventricular nucleus (AVPV). The two populations play distinct physiological roles in the HPG axis. Arcuate Kiss1 neurons have been implicated in the integration of various endogenous and environmental cues including endocrine and metabolic cues in the HPG axis. This study sought to profile candidate receptor gene expression in ARC Kiss1 (Kiss1ARC) neurons, based on previous neuronal tracing data suggesting innervations emanating from the paraventricular and ventral tuberomammillary nuclei. Reverse Transcriptase – Polymerase Chain Reaction (RT-PCR) from cytoplasm of single cells or pools of cells of adult transgenic heterozygous Kiss1/Cre female mice was performed. Results revealed Kiss1ARC neurons express serotonin and histamine receptors, but not corticotropin releasing hormone, thyrotropin releasing hormone, oxytocin, or vasopressin receptors. To further understand the molecular and physiological uniqueness of Kiss1ARC and AVPV Kiss1 (Kiss1AVPV) neurons, unbiased transcriptomic profiling was done using RNA-sequencing on pools of Kiss1 neurons obtained by enzymatic dissociation of brain tissue. Principal component analysis revealed a clear clustering of Kiss1AVPV neurons from the Kiss1ARC neurons, while caudal Kiss1ARC neurons did not separate from rostral Kiss1ARC neurons. There were 332 differentially expressed genes between the Kiss1ARC and Kiss1AVPV neurons. A transcriptomic profile of genes highly and differentially expressed in both populations was generated. Pathway analysis and Gene Set Enrichment Analysis revealed pathways that are differentially enriched in the two populations, including the catecholaminergic biosynthesis pathway highly enriched in Kiss1AVPV neurons. To study the reproductive effect of the catecholamine biosynthesis disruption in Kiss1 neurons, the common enzyme in the biosynthesis of serotonin and all catecholamines, dopa decarboxylase (Ddc), was selectively ablated in Kiss1 neurons using CRE-Lox technique. There was no observable difference in fertility and fecundity parameters between wild-type and knockout mice. Thus, the role of serotonin and catecholamine biosynthesis pathway in Kiss1AVPV neurons remains unknown. In summary, the data in this thesis shows that serotonin and histamine may modulate the central reproductive axis via Kiss1ARC neurons while stress related peptides, corticotropin releasing hormone, thyrotropin releasing hormone, oxytocin and vasopressin may modulate the reproductive axis indirectly, not through Kiss1ARC neurons. While Kiss1ARC neurons and Kiss1AVPV neuronal populations have many transcriptional similarities, they also have several differentially expressed genes which may help explain their distinct physiological roles as integration centres in the reproductive axis. This knowledge may be exploited further to better understand and delineate the physiological, molecular, and embryonic origins of the two populations and serve as basis for further investigations into potential therapeutic targets for disorders of the HPG axis as well as development of novel contraceptive therapy.