Summary
The purpose of this study was to determine the specificity of the response of medial preoptic-septal neurons (mPOA-S) to microelectrophoresed 17β-estradiol hemisuccinate (17βE2S). In vitro studies were conducted initially to determine the release of the labeled 17βE2S from multibarrel glass micropipettes. Subsequently, an isomer of 17βE2S, 17α-estradiol hemisuccinate (17αE2S), was synthesized and purified. Thirty-six mPOA-S neurons from normal cycling female rats were tested with both 17βE2S and 17αE2S. Twelve of these units responded with inhibition to 17βE2S, while none responded to 17αE2S. Furthermore, fifty extrahypothalamic (cortical, hippocampal, thalamic) neurons were tested with 17βE2S. The majority (N = 45) showed no response, three showed excitation and two inhibition to the microelectrophoresed steroid ester. These findings suggest that a specific receptor mechanism is responsible for the changes in mPOA-S unit activity, and that these effects may be important in the regulation of reproductive events.
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Supported by NIH Grant NS10434-END, awarded to R.L. Moss
Presently an NIH Postdoctoral Fellow at Max-Planck Institute for Biophysical Chemistry, Göttingen, West Germany
Recipient of an USPHS Career Development Award No. HD00146
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Kelly, M.J., Moss, R.L., Dudley, C.A. et al. The specificity of the response of preoptic-septal area neurons to estrogen: 17α-estradiol versus 17β-estradiol and the response of extrahypothalamic neurons. Exp Brain Res 30, 43–52 (1977). https://doi.org/10.1007/BF00237857
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DOI: https://doi.org/10.1007/BF00237857