Putative serotonin reuptake inhibitor-induced spawning and parturition in freshwater bivalves is inhibited by mammalian 5-HT2 receptor antagonists.
Selective serotonin reuptake inhibitors (SSRIs) can mimic the physiological actions of serotonin, and in bivalve molluscs they induce zebra mussel spawning and fingernail clam parturition. We have elucidated further the pharmacology of SSRI-induced spawning and part-urition by blocking these reproductive processes with two mammalian 5-HT(2) receptor antagonists, cyproheptadine and mianserin. These two antagonists were potent inhibitors of both spawning and parturition induced by the SSRIs fluvoxamine, fluoxetine, and zimelidine. In zebra mussels, both cyproheptadine and mianserin significantly blocked spawning induced by fluvoxamine and by zimelidine. In the fingernail clams Sphaerium spp., both cyproheptadine and mianserin blocked fluvoxamine-induced parturition. A possible mechanism of action for SSRI-induced spawning and parturition in bivalves is suggested.
Fong
Peter P
PP
Department of Biology, Gettysburg College, Gettysburg, Pennsylvania 17325, USA. pfong@gettysburg.edu
Philbert
Caroline M
CM
Roberts
Brian J
BJ
D000818:Animals; D008974:Mollusca / Q000502:physiology*; D012098:Reproduction / Q000187:drug effects; D012702:Serotonin Antagonists / Q000494:pharmacology*; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology*; D012726:Sexual Behavior, Animal / Q000187:drug effects*
D012702:Serotonin Antagonists; D017367:Selective Serotonin Reuptake Inhibitors