Increased 5-hydroxytryptamine and norepinephrine release from rat brain slices by the Red Sea flatfish toxin pardaxin.
The effect of the Red Sea flatfish toxin pardaxin was examined on K+-evoked and on basal release of either [3H]norepinephrine or [3H]5-hydroxytryptamine from preloaded rat cortical slices. The K+-induced release of the neurotransmitters was stimulated in a dose-related manner at concentrations ranging from 0.5 to 4 micrograms/ml. Basal release of the two transmitters was elevated to a lesser extent. Although the stimulation of evoked release was approximately equivalent for the two neurotransmitters, the response to 5-hydroxytryptamine was reversible whereas that of norepinephrine was not washed by 20 min of superfusion. The mechanisms involved in producing these actions of pardaxin are not known; however, they may be mediated by changes in electrolyte fluxes across the neuronal membranes.
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D005397:Fish Venoms / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D010296:Parietal Lobe / Q000187:drug effects / Q000378:metabolism; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D012701:Serotonin / Q000378:metabolism*
D005397:Fish Venoms; D012701:Serotonin; C017603:pardaxin; D011188:Potassium; D009638:Norepinephrine