Title of Grant Funded:
Cognitive function in a transitional versus surgical rat model of menopause
Grant Findings:
Our initial IMHR pilot grant evaluated whether surgical menopause initiated cognitive effects that differed from transitional menopause. It was only recently that cognitive effects of a transitional menopause model could be evaluated. Dr. Mayer and colleagues discovered that 4‐vinylcyclohexene diepoxide (VCD) results in ovarian follicular depletion in the rodent. In this rat model, after a gradual deterioration of follicles resulting in an ultimately extensive loss of follicular reserves, gonadal hormone and gonadotropin profiles are remarkably comparable to those of menopausal women. In our first IMHR grant in collaboration with Dr. Mayer, we found that transitional, gradual loss of ovarian hormones (induced via VCD) was better for cognition than abrupt ovarian hormone loss via surgical menopause. This transitional hormone loss benefited cognition only if the residual ovary was removed; this paper was recently published in Endocrinology (Acosta et al., 2009) and we have a second paper stemming from this work in review (we just submitted the revision in May, 2010) in Endocrinology as well. This is the top journal in the field, so we are thrilled that this research has been published into the journal. Of note, the initial IMHR VCD paper was also chosen as the top research finding in Endocrine Notes, 2009, by the Endocrine Society. In the brains of the animals receiving different menopause types from the initial paper, we examined the vesicular acetylcholine transporter (VAChT) since we previously found Premarin affected the basal forebrain cholinergic system (Acosta et al., 2009b). We found no treatment group differences in these hippocampal measurements.
Additional Grants Received: