Stimulation of<i>Spisula</i>sperm motility by 5-hydroxytryptamine analogs

Abstract

Summary Serotonin (5-hydroxytryptamine, 5-HT) added to cold-immobilized Spisula sperm reinitiated motility. The response was instantaneous and dose-dependent at concentrations ranging from 1 to 5 μm. The 5-HT agonists, 8-OH-DPAT, 5-methoxytryptamine and 2-methyl-5-HT, were effective inducers while RU 24969 and 5-hydroxyindole-3-acetic acid were not. Paralleling the stimulation of sperm motility, 5-HT increased oxygen consumption of Spisula sperm, reflecting acceleration of respiration. Of the various species tested, 5-HT stimulated only Spisula sperm. Key words: serotoninsperm motilityoxygen consumption Spisula gametes