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Published on: January 16, 2014
Hypothalamic epinephrine is released into hypophysial portal blood during stress
Abstract:
The hypothalamic secretion of epinephrine (EPI), norepinephrine (NE), and dopamine (DA) into hypophysial portal blood was studied in adrenalectomized rats subjected to heat stress. Portal plasma EPI levels were increased 3-fold by heat stress whereas portal plasma concentrations of NE and DA were not altered by stress. These data suggest that EPI of hypothalamic origin may be involved directly in the modulation of anterior pituitary secretion during stress.
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