Preferential vulnerability of dendrites to lithium ion in rat brain and in nerve cell culture.

Preferential swelling and vacuolation of dendrites were observed electron microscopically in different brain regions of rats treated with LiCl in a dose of 6-18 mmol/kg for 1-6 days. The most severe fine structural changes were revealed in the hippocampus. Low-dose (0.33 mmol/kg) lithium treatment lasting for a year did not cause any morphologically detectable alterations in the rat brain. In vitro studies showed a reduction of dendro-axonal process network of neurons measured by morphometric means after lithium exposure. Using different cultures of neuronal and glial cell populations, higher lithium uptake was observed for neuron-enriched cultures.