Dramatic Rises of Melatonin and 5-Methoxytryptamine in Gonyaulax Exposed to Decreased Temperature
| Autor: | Ruediger Hardeland, B Poeggeler, B. Fuhrberg, C Behrmann |
|---|---|
| Rok vydání: | 1997 |
| Předmět: |
medicine.medical_specialty
Elevated level Physiology Dinoflagellate Biology biology.organism_classification medicine.disease Melatonin chemistry.chemical_compound Endocrinology chemistry 5-Methoxytryptamine Physiology (medical) Internal medicine medicine Cyst formation Gonyaulax Cyst Circadian rhythm Ecology Evolution Behavior and Systematics medicine.drug |
| Zdroj: | Biological Rhythm Research. 28:144-150 |
| ISSN: | 1744-4179 0929-1016 |
| DOI: | 10.1076/brhm.28.1.144.12978 |
| Popis: | The dinoflagellate Gonyaulax polyedra was previously shown to undergo asexual encystment in response to decreased temperature (15° instead of 20°C rearing temperature) in combination with short-days, a response which can be mimicked by melatonin and, much more efficiently, by 5-methoxytryptamine (= 5-MT). We demonstrate that these cyst-inducing conditions lead to enormous accumulations of the two methoxyindoleamines. The circadian rhythmicity of melatonin is maintained for the two days usually preceding cyst formation, though, at an elevated level. Transiently, very high concentrations of melatonin can occur, eventually exceeding 1 millimolar. These extreme concentrations decay rapidly; during this decline, 5-MT and 5-methoxytryptophol appear in large amounts. The concentrations of 5-MT which are measured during this process are higher than those required for cyst induction by the exogenous indoleamine. |
| Databáze: | OpenAIRE |
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