Changes in the chain length of folylpolyglutamates during liver regeneration.

Partial hepatectomy significantly alters the proportions of folylpolyglutamates of different chain lengths in rat liver. Hexa- and heptaglutamates increase at the expense of tetra- and pentaglutamates. Methyl hexaglutamates account for most of the increase in hexaglutamates, and folates with formyl oxidation-level one-carbon substituents for most of the increase in heptaglutamates. These changes are reversible and believed to represent an element of regulation of one-carbon metabolism.