Modulation of outgrowth from goldfish retinal explants by a 5-HT2 receptor agonist and [3H]ketanserin binding sites in goldfish and rabbit retina.
The binding of [3H]ketanserin to goldfish and rabbit retinal membrane preparations and the possible role of 5-HT2A receptors in the in vitro outgrowth from goldfish retina were evaluated. Saturation experiments indicated a high-affinity binding site, and positive cooperativity for both tissues. The 5-HT2A/2C agonist (+/-)-2,5-dimetoxy-4-iodoamphetamine and serotonin inhibited outgrowth from goldfish retinal explants. These effects were blocked by the 5-HT2 antagonists ketanserin and 1-(1-naphthyl)piperazine and by the 5-HT2C antagonist mesulergine, respectively. Results make to suggest that [3H]ketanserin binds to 5-HT2A receptors in the rabbit and goldfish retina, but also to a monoamine transporter in the latter tissue. Subtypes of 5-HT2 receptors might mediate the 5-HT modulatory role on in vitro outgrowth of the goldfish retina.
Schmeer
C
C
Laboratorio de Neuroquímica, Instituto Venezolano de Investigaciones Científicas, Caracas, Venezuela. cschmeer@cbb.iviv.ve
Lima
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L
D000818:Animals; D001665:Binding Sites; D046508:Culture Techniques; D006054:Goldfish / Q000378:metabolism*; D007650:Ketanserin / Q000378:metabolism*; D011817:Rabbits / Q000378:metabolism*; D012038:Regeneration / Q000187:drug effects; D012160:Retina / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*
D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; D007650:Ketanserin