Side effects of lithium on rat cranial arachnoid and dura mater collagen: A quantitative ultrastructural study

Lithium is widely used in medicine as an antidepressive drug. Despite abundant literature on the subject, questions on the effects of lithium on collagen, which is one of the major components of tissues and organs, are far from being answered. We have examined the effects of lithium chloride (1.5 meq/kg of body weight) on rat cranial arachnoid and dura mater collagen fibrils by electron microscopy and image analysis. Animals were sacrificed 1 day, 2, 6, and 12 months after the end of a 30-consecutive days experimental period. In all cases investigated, severe structural abnormalities in collagen fibrils, at the ultrastructural level, were found. These abnormalities consist of decreased mean diameter and irregularity of shape of collagen fibrils (when viewed in cross sections) as well as marked disorganization in the packing of the fibrils. The observed alterations seem to be permanent. J. Trace Elem. Exp. Med. 16:17–26, 2003. © 2003 Wiley-Liss, Inc.