State-dependent retention (SDR) has frequently been demonstrated with
drug-induced physiological changes which apparently serve as contextua
l cues for memory. These support the assumption that commonly occurrin
g endogenous dispositions play a role in memory, yet there are few rep
orts showing SDR with states that are likely to be part of an organism
's natural experiences. To determine if behavioral estrus could produc
e SDR, ovariectomized female rats were rendered estrus via hormone inj
ections or remained anestrus via placebo injections, trained with quin
ine-laced apple juice, and later tested while in the same or different
state for reactions towards pure juice. SDR was not evident in the am
ount of juice consumed; however, those tested in the same state as the
initial experience were slower to initiate drinking than those tested
in a different state revealing a state-dependent influence on memory
related to phases of the ovarian cycle.