The Lee–Boot effect is a phenomenon concerning the suppression or prolongation of oestrous cycles of mature female mice (and other rodents), when females are housed in groups and isolated from males.[1][2] It is caused by the effects of an estrogen-dependent pheromone, possibly 2,5-dimethylpyrazine,[3] which is released via the urine and acts on the vomeronasal organ of recipients.[4][5] This pheromone lowers the concentration of luteinizing hormone and elevates prolactin levels, synchronising or stopping the recipient's cycle.[6] This effect goes some way to explain why spontaneous pseudopregnancy can occur in mice. The same response is invoked from isolated females when brought into contact with urine-soaked bedding from other females' cages. The adrenal glands are required for production of the urine pheromone which is responsible for this effect.[3]
^ abMa W, Miao Z, Novotny MV (1998). "Role of the adrenal gland and adrenal-mediated chemosignals in suppression of estrus in the house mouse: the Lee-Boot effect revisited". Biol Reprod. 59 (6): 1317–20. doi:10.1095/biolreprod59.6.1317. PMID9828173.{{cite journal}}: CS1 maint: multiple names: authors list (link)