MOUSE STRAIN AND SOURCE OF L-TRYPTOPHAN AFFECTS HEPATIC NUCLEAR TRYPTOPHAN BINDING

This study describes that the affinity for specific L-tryptophan bindi ng to hepatic nuclei in vitro is markedly decreased in NZBWF(1) mice i n comparison to that in Swiss mice. Also, the hepatic nuclei of NZBWF( 1) mice have a significantly decreased binding response in vitro to Sh owa Denko L-tryptophan (implicated in the eosinophilia-myalgia syndrom e) or to its contaminants, 1,1'-ethylidenebis(tryptophan) or 3-phenyla mino-L-alanine, when each is added to control, non-implicated L-trypto phan compared with hepatic nuclei of Swiss mice. Enhanced hepatic prot ein synthesis induced by tube-feeding control L-tryptophan is much les s in NZBWF(1) mice than in Swiss mice. Tube-feeding of Showa Denko L-t ryptophan induced less stimulation of hepatic protein synthesis than d id control L-tryptophan in Swiss mice but essentially none in NZBWF(1) mice. NZBWF(1) mice have a genetically altered response to L-tryptoph an which may prove to be useful is studying the role of L-tryptophan i n health and in disease. (C) 1997 Elsevier Science Ireland Ltd.