Lithium-mediated long-term neuroprotection in neonatal rat hypoxia-ischemia is associated with antiinflammatory effects and enhanced proliferation and survival of neural stem progenitor cells

The aim of this study was to evaluate the long-term effects of lithium treatment on neonatal hypoxic-ischemic brain injury, inflammation, and neural stem/progenitor cell (NSPC) proliferation and survival. Nine-day-old male rats were subjected to unilateral hypoxia–ischemia (HI) and 2 mmol/kg lithium chloride was injected intraperitoneally immediately after the insult. Additional lithium injections, 1 mmol/kg, were administered at 24-hour intervals for 7 days. Animals were killed 6, 24, 72 hours, or 7 weeks after HI. Lithium reduced total tissue loss by 69%, from 89.4±14.6 mm3 in controls (n = 15) to 27.6 ±6.2 mm3 in lithium-treated animals (n = 14) 7 weeks after HI (P