Fig. 1.

Experimental treatment paradigm and OVX rat model. Ovaries were surgically removed from young adult female rats 2 wk before sc injection with E2, MPA, E2+MPA, or oil vehicle control. Sham OVX rats, determined to be in the morning of the estrous phase of the cycle served as a positive control. Twenty-four hours after the treatment, whole-brain mitochondria from the left hemisphere of the forebrain were isolated and subjected to a series of functional assessment experiments. The hippocampus was dissected from the right hemisphere of the forebrain and used to determine the expression of the mitochondrial proteins.