Summary
Electron microscopical evidence for the existence of an important serotonergic input to the rat median eminence is presented. This evidence is based on the demonstration of degenerating nerve terminals in the external layer of the rat median eminence following the application of 5,6-dihydroxytryptamine or 5,7-dihydroxytryptamine, drugs known to exert more or less selective toxic effects on central serotonin neurons.
The finding of a serotonergic innervation of the median eminence in mammals has important implications for 5-hydroxytryptamine as a modulator of synthesis and/or release of hypothalamic, hypophysiotropic hormones.
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Supported by grants from the Deutsche Forschungsgemeinschaft.
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Baumgarten, H.G., Lachenmayer, L. Indoleamine-containing nerve terminals in the rat median eminence. Z.Zellforsch 147, 285–292 (1974). https://doi.org/10.1007/BF00582802
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DOI: https://doi.org/10.1007/BF00582802