Effects of 17a-estradiol treatment on hippocampal abmonrmalities of spontaneously hypertensive rat (SHR).

PIETRANERA, LUCIANA; BROCCA, M. ELVIRA; ROIG, PAULINA; DE NICOLA, ALEJANDRO F.

Torino

Congreso; 7th International Meeting Steroids and Nervous System; 2013

Hippocampal neuropathology is a recognized feature of the spontaneously hypertensive rat (SHR). In previous studies we have found that SHR present abnormalities in the hippocampus consisting of decreased cell proliferation in the dentate gyrus (DG), astroglial reactivity and decreased neuronal density in the hilus of the DG. These abnormalities are reversed by 17b-estradiol, an active neuroprotective agent.  17a-estradiol, an optical isomer of 17b-estradiol, has lower affinity for ER classical receptors and therefore much less feminizing and carcinogenic actions. However, neuroprotective actions of this molecule have been reported. These actions could be mediated by membrane receptors such as GABAa, GPR-30 or ERX. In this work, we attempted to investigate possible neuroprotective actions of 17a-estradiol on the hippocampal neuropathology of SHR. We treated 16 week old male SHR (mean arterial pressure: 180 Hgmm) and normotensive WKY rats with 17a-estradiol or cholesterol pellets during two weeks. Animals were sacrificed and brains removed. We studied cellular proliferation in the dentate gyrus by the expression of Ki67 and astroglial reactivity by GFAP expression in stratum radiatum of the hippocampus.  17a-estradiol treatment was able to increase cellular proliferation in the DG of SHR rats (p