 Many studies show that kisspeptin has the ability to not only cause depolarization, but also excite many GnRH neurons, leading to high expression of kisspeptin in these genes.But, it is hypothesized that there are two different types of GFP-GnRH neurons due to expression in some neurons but not others, only one of which responds to kisspeptin.The neurons response to kisspeptin is also hypothesized to be related to age and puberty.