Numerous experiments in our laboratory have shown that exposure to an acute stressful experience facilitates associative learning in male rats and dramatically impairs learning in female rats. We have also found sex differences and opposing effects of stress on dendritic spine density in the hippocampus of males versus females. In males, spine density is enhanced after exposure to an acute stressor, while the density of dendritic spines in females is reduced. Based on this series of observations, we have proposed that the stress effects on learning are mediated by the stress effects on spine density. To address this hypothesis, I will test whether the opposite effects of stress on earning in males versus females. In males, the stress-induced facilitation of learning is dependent on the stress-related adrenal hormones, glucocorticoids. The stress-induced impairment of learning in females is not dependent on the stress-related glucocorticoids, but is dependent on the ovarian hormone estrogen. Thus, the goal of my proposal is to determine whether glucocorticoids in males and estrogen in females contribute to the sexually opposed stress on dendritic spine density.
| Leuner, Benedetta; Shors, Tracey J (2006) Learning during motherhood: A resistance to stress. Horm Behav 50:38-51 |
| Leuner, Bendetta; Mendolia-Loffredo, Sabrina; Kozorovitskiy, Yevgenia et al. (2004) Learning enhances the survival of new neurons beyond the time when the hippocampus is required for memory. J Neurosci 24:7477-81 |
| Shors, T J; Falduto, J; Leuner, B (2004) The opposite effects of stress on dendritic spines in male vs. female rats are NMDA receptor-dependent. Eur J Neurosci 19:145-50 |
| Leuner, B; Mendolia-Loffredo, S; Shors, T J (2004) High levels of estrogen enhance associative memory formation in ovariectomized females. Psychoneuroendocrinology 29:883-90 |
| Leuner, Benedetta; Mendolia-Loffredo, Sabrina; Shors, Tracey J (2004) Males and females respond differently to controllability and antidepressant treatment. Biol Psychiatry 56:964-70 |
| Leuner, Benedetta; Shors, Tracey J (2004) New spines, new memories. Mol Neurobiol 29:117-30 |
| Leuner, Benedetta; Falduto, Jacqueline; Shors, Tracey J (2003) Associative memory formation increases the observation of dendritic spines in the hippocampus. J Neurosci 23:659-65 |
| Shors, Tracey J; Leuner, Benedetta (2003) Estrogen-mediated effects on depression and memory formation in females. J Affect Disord 74:85-96 |
