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) = serotonin(in) + chloride(in) + na(+)(in)