serotonin(in) + chloride(in) + Na(+)(in) => serotonin(out) + chloride(out) + Na(+)(out)
serotonin(in) + chloride(in) + na(+)(in) => serotonin(out) + chloride(out) + na(+)(out)
serotonin(in) + chloride(in) + Na(+)(in) => serotonin(out) + chloride(out) + Na(+)(out)
serotonin(in) + chloride(in) + na(+)(in) => serotonin(out) + chloride(out) + na(+)(out)