Effect of 17β estradiol on hippocampus region of aging female rat brain: Ultrastructural study

Rashmi Jha, Ranjeet Kumar, Priyanka Mishra, Abbas Ali Mahdi, Shivani Pandey, Najma Zaheer Baquer, Sudha Mahajan Cowsik


Estradiol has direct membrane-mediated effects on neurons and its effects are both neuroprotective and neurotrophic. This hormone modulates brain development and aging and affects neurochemical systems which are affected in age-related cognitive decline, AD and other neuropsychiatric disorders. The aim of the present study was to determine the effect of 17β estradiol (E2) in hippocampus region of different age groups of rats. The changes in the hippocampus region of female rat brain of different age groups with and without E2 treatment were observed by transmission electron microscopy. Age dependent changes in myelin sheath, axon and cytoplasm membrane were observed with aging in control group rat brain but the E2 treated rats showed significantly stable myelin sheath, myelin axon and cytoplasm structure. Our results showed that E2 treatment significantly effects hippocampus brain region of aging rats. These analyses revealed that fundamental age-related changes in brain and estrogen have important implications when estrogen levels and hippocampus dependent functions decline.


Brain aging, estradiol, estrogen receptor, hippocampus

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