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Updated: Aug 11, 2026
Isolation and Culture of Hippocampal Neurons from Prenatal Mice
Published on: July 26, 2012
Early postnatal stimulation alters pregnane neurosteroids in the hippocampus
Cheryl A Frye1, Madeline E Rhodes, YogendraSinh H Raol
1Department of Psychology, University at Albany, Albany, NY 12222, and Division of Neurology, The Children's Hospital of Philadelphia, PA, USA. cafrye@albany.edu
Rationale:
The progesterone metabolite 5alpha-pregnane-3alpha-ol-20-one (3alpha,5alpha-THP) is an important modulator of the hypothalamic-pituitary-adrenal axis and stress-induced corticosterone response. Typically, 3alpha,5alpha-THP levels are increased in response to acute stress, which may then reduce corticosterone release from the adrenals. Early postnatal stimulation is a developmental stressor that can produce pervasive endocrine effects.
Objectives:
The present studies investigated the effects of early postnatal stimulation on plasma progestin and corticosterone levels and hippocampal progestin levels of rats.
Methods:
On postnatal days 9 and 10, rats were either left in their home cage undisturbed or injected intraperitoneally as a means of early stimulation (ES). Tissues were collected on either postnatal day 10 (6 h after last handling experience) or adulthood. Plasma corticosterone, progesterone, and 3alpha,5alpha-THP and hippocampal progesterone and 3alpha,5alpha-THP were measured by radioimmunoassay.
Results:
On postnatal day 10, plasma, but not hippocampal, levels of progesterone and 3alpha,5alpha-THP were significantly lower among rats exposed to ES than control rats. These effects occurred concomitant with a tendency for plasma corticosterone to be higher among ES compared to control rats. In adulthood, hippocampal 3alpha,5alpha-THP was significantly lower among ES vs control rats.
Conclusions:
Together, these data suggest that ES may influence immediate secretion of 3alpha,5alpha-THP and corticosterone and have pervasive effects in adulthood on the biosynthesis and/or metabolism of progestins in the hippocampus.
