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Updated: Aug 16, 2026

A Rat Methyl-Seq Platform to Identify Epigenetic Changes Associated with Stress Exposure
Published on: October 24, 2018
Effect of stress and cholinergic stimulation on ACTH release in alpha-methyl-dopa pretreated rats
Abstract:
Pituitary-adrenocortical function and the changes of hypothalamic catecholamine content were studied following alpha-methyl-dopa treatment in rats. After three-day administration of alpha-methyl-dopa the plasma corticosterone concentration increased significantly and at the same time ether stress failed to elicit a pituitary-adrenocortical response. Moreover, the alpha-methyl-dopa pretreatment prevented the facilitatory effect of physostigmine on pituitary-adrenocortical activation. As the result of alpha-methyl-dopa treatment the norepinephrine content decreased significantly and the amount of compounds measured as dopamine (dopamine, alpha-methyl-dopamine and alpha-methyl-dopa) increased in the hypothalamus. It is concluded that the impaired metabolism of catecholamines may inhibit the pituitary-adrenocortical activation to stimulation, and that not only norepinephrine and dopamine, but other phenylalanine derivatives and alpha-methyl-dopa may also influence the responsiveness of pituitary-adrenocortical function.
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