ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: Serotonin (5-hydroxytryptamine, 5-HT; 0.5 μM and above) stimulated the release of [3H]dopamine ([3H]DA) from particulate fractions of the carp (Cyprinus carpio) retina. The 5-HT effect was dose- and Ca2+-dependent, and was structurally specific. A similar response was not elicited by the other indoles (5,6-dihydroxytryptamine, 5,7-dihydroxytryptamine, 5-hydroxytrypto-phan, or 5-hydroxyindoleacetic acid) examined. An increase in [3H]DA release was elicited by addition of 5-HT agonists (5-methoxytryptamine, 5-methoxy-N,N- dimethyltryptamine, and tryptamine), but not antagonized by three 5-HT antagonists (metergolin, methysergide, and spiperone). Either DA alone or noradrenaline (0.5 mM) produced a large increase in [3H]DA release from the particulate fractions, but this action was Ca2+-independent. Further, no significant release of [3H]γ-aminobutyric acid could be evoked by 5-HT (0.5 mM) under similar experimental conditions. Taken together, the present data suggest that 5-HT stimulates [3H]DA release from the fish retina through a specific receptor-mediated mechanism on dopaminergic terminals, but not through an exchange or nonspecific phenomenon.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1982.tb03971.x
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