Lithium and actin: an intriguing interaction

Lithium ions have a very long history in both experimental embryology and psychiatric therapy. Lithium is known to alter the developmental pattern of embryos, mainly by disturbing the establishment of embryonic axes. In medicine, on the other hand, lithium ions are largely used as an antimanic drug. Despite the wide experimental use of lithium, the molecular bases of its biological activity are far from being fully understood and still form the basis of exciting discussions. At present, many of the suggestions seem to converge towards a single, principal biological target: the cycle of phosphatidyl inositide phosphates. In this paper we propose a different, additional point of view from which to look at the problem. Since lithium interacts with cytoskeletal biopolymers (F-actin and microtubules) mainly by enhancing their stability and consequently depressing their physiological dynamics, we suggest that the teratogenic activity of lithium, as well as its behavioural control of highly active patients, could both be related to the influence of lithium on intracellular motility.