Correlation between hypothalamic catecholamine synthesis and ether stress-induced ACTH secretion.

G A Hedge; J M van Ree; D H Versteeg

doi:10.1159/000122528

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Correlation between hypothalamic catecholamine synthesis and ether stress-induced ACTH secretion.

G A Hedge·J M van Ree·D H Versteeg

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Abstract

The rates of synthesis of norepinephrine (NE) and dopamine (DA) in several regions of the hypothalamus have been estimated after exposure of rats to stresses that increase ACTH secretion. The rate of 3H-NE and 3H-DA accumulation from 3H-tyrosine in vitro was used as an index of catecholamine synthesis rates. Exposure to ether vapor, 30 min of cold environment, or laparotomy increased ACTH secretion significantly, as indicated by plasma corticosterone levels. However, only the ether stress affected hypothalamic catecholamines; both NE and DA synthesis rates were increased in the arcuate nucleus are (ANA), but not in the median eminence (ME) or the residual hypothalamus (RH). Dexamethasone treatment blocked the stress-induced ACTH secretion, but had no affect on basal or stress-induced rates of amine synthesis. It is concluded that catecholamines in the ANA participate in mediating ether stress-induced ACTH secretion.

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Adrenocorticotropic Hormone Animals Catecholamines Corticosterone Dopamine Ether Hypothalamus Male Norepinephrine Rats Stress, Physiological Tyrosine Journal Article Research Support, U.S. Gov't, P.H.S.

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G A Hedge, J M van Ree, D H Versteeg. 1976. Correlation between hypothalamic catecholamine synthesis and ether stress-induced ACTH secretion.. https://doi.org/10.1159/000122528

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