Effects of acute oral administration of lithium compounds on multiple schedule performance in rats

Adult male Sprague-Dawley rats were given acute oral administrations of lithium carbonate or lithium chloride at concentrations of 100, 200, and 300 mg/kg. Barpressing performance on a multiple fixed ratio 20/fixed interval 5 minute schedule was measured daily. The 200 and 300 mg/kg administrations of lithium chloride produced significant decreases in barpressing performance and all levels of lithium carbonate produced significant changes in performance. A 24 hour delay in the maximal behavioral effect of the 300 mg/kg dose of lithium carbonate paralleled previous findings showing delays in peak brain lithium levels after oral administration of lithium carbonate.