Increased EPSP amplitude at the crayfish neuromuscular junction for acute but not chronic exposure to fluoxetine

Abstract

The exact manner in which fluoxetine, a selective serotonin reuptake inhibitor (SSRI) and the active ingredient in Prozac, affects the nervous system of humans or any other organism is unknown. Our experiment aimed to determine the effects of acute and chronic exposure to fluoxetine at the crayfish neuromuscular junction. Though the excitatory neurotransmitter in the crayfish nervous system is glutamate, not serotonin, we aimed to determine whether fluoxetine may have similar effects on the glutametergic synaptic system of the crayfish. We measured excitatory postsynaptic potential (EPSP) amplitudes of three populations of crayfish: chronic exposure to water, acute exposure to fluoxetine, and chronic exposure to fluoxetine. We determined that average EPSP amplitude increased relative to the control value for acute but not chronic exposure. Our experiment suggests that fluoxetine has an excitatory effect at the crayfish neuromuscular junction.