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PARTICIPATION OF DOPAMINE‐ AND SEROTONIN‐RECEPTORS IN THE DISAGGREGATION OF BRAIN POLYSOMES BY l ‐DOPA AND l ‐5‐HTP
Author(s) -
Weiss B. F.,
Liebschutz J. L.,
Wurtman R. J.,
Munro H. N.
Publication year - 1975
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1975.tb03897.x
Subject(s) - methysergide , pimozide , dopamine , cyproheptadine , haloperidol , serotonin , chemistry , apomorphine , decarboxylase inhibitor , endocrinology , medicine , dopamine receptor , tryptamine , receptor , pharmacology , dopaminergic , biology , biochemistry , levodopa , disease , parkinson's disease
— It has previously been shown that the disaggregation of brain polysomes and suppression of brain protein synthesis observed in rats given the amino acids l ‐dopa or l ‐5‐HTP is mediated by the decarboxylation products dopamine and serotonin. Present studies demonstrate that the poly‐some disaggregation is caused by the interactions of the monoamines with specific receptor sites. Thus, dopa‐induced disaggregation is blocked if rats are pretreated with haloperidol or pimozide (but not methysergide or cyproheptadine), while 5‐HTP‐induced disaggregation is blocked by methysergide or cyproheptadine (but not by haloperidol or pimozide). Pretreatment of rats with MK‐486, a drug that inhibits dopa decarboxylase in blood vessels and peripheral tissues but not brain, does not block dopa‐induced brain polysome disaggregation; hence this disaggregation depends on the interaction of dopamine with receptors in the brain parenchyma. Brain polysomes are not disaggregated in rats given intraperitoneal apomorphine (or intracisternal dopamine). The disaggregation caused by dopa is not reduced in animals pretreated with sufficient intracisternal 6‐hydroxydopamine to cause major damage to catecholaminergic nerve terminals.