Pineal methoxyindoles depress calcium uptake by rat brain synaptosomes.
The effect of several pineal methoxyindoles on 45Ca2+-uptake was examined in a crude synaptosome preparation from adult rat brains. 5-Methoxytryptol, 5-methoxytryptamine, melatonin and 6-chloromelatonin (10(-8)-10(-6) M) depressed significantly the K+-stimulated increase in Ca2+-uptake, without affecting the basal, unstimulated Ca2+-uptake by synaptosomes. At 10(-6) M concentration the following order of potency was found: 6-chloromelatonin greater than or equal to 5-methoxytryptamine greater than 5-methoxytryptophol greater than or equal to melatonin. Serotonin did not affect significantly either basal or stimulated Ca2+-uptake.
D008735:5-Methoxytryptamine / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D005260:Female; D066298:In Vitro Techniques; D007211:Indoles / Q000494:pharmacology*; D008550:Melatonin / Q000031:analogs & derivatives / Q000494:pharmacology; D010870:Pineal Gland / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000494:pharmacology; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism*
D007211:Indoles; D012701:Serotonin; D008735:5-Methoxytryptamine; C024100:6-chloromelatonin; C002465:methoxytryptophol; D008550:Melatonin; D002118:Calcium