Aberrant growth of mossy fibers and enhanced kainic acid binding sites induced in rats by early hyperthyroidism.

Early hyperthyroidism induces an aberrant growth of hippocampal mossy fibers both in the fascia dentata (supragranular layer) and in Ammon's horn (infrapyramidal layer of CA3). Using a quantitative autoradiographic method, we found a corresponding increase in kainic acid binding sites supporting previous observations of a very close association between mossy fiber terminals and kainic acid binding sites.