Pertussis vaccine and pertussis toxin increase lithium levels in rats: possible role of G-proteins.
A single dose of lithium was injected intravenously or intraperitoneally in rats. Lithium levels in serum and tissues 5 or 24 hours later were elevated when the rats were pretreated with pertussis vaccine (PV). The vaccine was effective whether given locally (subcutaneous) or systemically (intravenous). Tests of heated (inactivated) PV suggested that pertussis toxin might be responsible for the effects of PV. Injection of purified pertussis toxin (PT) confirmed this suggestion. Elevation of serum urea nitrogen suggested that lithium levels were increased because the combination of PV or PT with lithium reduced renal excretory function which could cause retention of lithium. Inasmuch as PV and PT are known to inactivate the inhibitory G-proteins, these data suggest G-protein involvement in the elevation of lithium levels by PV and PT.