“Smell This!”

Welcome to the “Smell This!” page!


Here we will discuss pheromones and their reproductive value in mice. We will also review:

  1. The phylogeny of pheromone use in vertebrates including discussion about the vomeronasal organ (VNO) and the TRP2 signal transduction ion channel (Phylogeny)
  2. The current understandings of ontogenetic development of the VNO in mice (Ontogeny)
  3. The mechanism of pheromone-VNO pathway (Mechanism)
  4. The adaptive values of the pheromone pathway (Adaptive value)

Overall, we would like to show how the interpretation of pheromones by the VNO pathway affects aggressive and reproductive behaviors in mice, an interaction that is little understood today.

The term ‘pheromone’ was first introduced in 1959 by P. Karlson and M. Luscher and defined as “substances secreted to the outside of an individual an received by a second individual of the same species in which they release a specific reaction, for example, a definite behaviour or developmental process.” Pheromones were understood to be different from hormones in that “the substance is not secreted into the blood, but outside the body.” [Karlson & Luscher, 1959]

Today, pheromones are defined as non-volatile chemicals that are conspecific (species- specific) cues, which are generally not sensed in the main olfactory system (MOS). Pheromones are released to elicit stereotyped behaviors and neuroendocrine responses for reproduction, as well as maintaining social hierarchies in conspecifics. [Liman et al., 1999]. Pheromones are detected by the vomeronasal organ, which then interacts with the nervous system to provide information about the social and sexual status of the individuals in different species [Leypold et al., 2002]. The MOS is responsible for the recognition of odors from the environment, which may then induce a behavioral response [Leypold et al., 2002]. Therefore, the VNO and MOS detect different chemical compounds and differ in signal transduction.