ESTROGEN AND SEXUAL DIFFERENTIATION: IT'S IN THE TIMING
Reply to Rucklidge on Fitch & Denenberg on Sex-Brain

<hr> Roslyn Holly Fitch (1995) Estrogen and Sexual Differentiation: It's in the Timing. Psycoloquy: 6(24) Sex Brain (4)<br>Versions: <a href=ftp://www.cogsci.soton.ac.uk/pub/psycoloquy//1995.volume.6/psyc.95.6.24.sex-brain.4.fitch>ASCII</a> <a href=http://www.cogsci.ecs.soton.ac.uk/cgi/psyc/newpsy?6.24>formatted</a><hr>
<TITLE>Psycoloquy 6(24): Estrogen and Sexual Differentiation: It's in the Timing</TITLE>
<H1>ESTROGEN AND SEXUAL DIFFERENTIATION: IT'S IN THE TIMING<br>
Reply to Rucklidge on Fitch & Denenberg on Sex-Brain<br>
</H1>
<ADDRESS>Roslyn Holly Fitch<br>
Center for Molecular and Behavioral Neuroscience<br>
Rutgers University<br>
197 University Ave.<br>
Newark, NJ 07102<br>
<br>
Victor H. Denenberg<br>
Biobehavioral Sciences Graduate Degree Program<br>
University of Connecticut<br>
Storrs, CT 06269-4154<br>
<br>
<a href=mailto:holly@axon.rutgers.edu>holly@axon.rutgers.edu</a> 
<a href=mailto:dberg@uconnvm.uconn.edu>dberg@uconnvm.uconn.edu</a> 
</ADDRESS>
<P><H1>Abstract</H1><BLOCKQUOTE>
In asserting that a masculinizing role of estrogen
(derived via intracellular aromatization) is paradoxically
incompatible with a feminizing role of estrogen, Rucklidge (1995)
has overlooked the critical temporal distinction between the
sensitive windows for these effects. The fact that the neural
substrate (including but not limited to estrogen receptor
populations) is profoundly different in <P10 male as compared to
>P10 female rats, combined with the fact that physiological levels
of ovarian estrogen are much lower than those used to exogenously
induce masculinization, it should not be surprising that estrogen
could exert different effects (masculinizing versus feminizing) on
males versus females in two different developmental time-frames.
</BLOCKQUOTE>
<P><H1>Keywords</H1><i>
corpus callosum, development, estrogen, feminization,
ovaries, sensitive period.
</i>
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