Effect of stress and cholinergic stimulation on ACTH release in alpha-methyl-dopa pretreated rats
Debreceni, L.; Hartmann, G.
Acta Physiologica Hungarica 61(1-2): 99-103
1983
ISSN/ISBN: 0231-424X PMID: 6314745 Document Number: 204837
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.