2,3,7,8-tetrachlorodibenzo-p-dioxin induced alterations of pyruvate carboxylase levels and lactate dehydrogenase isozyme shifts in C57BL/6J male mice

✍ Scribed by Sparrow, Barney R. ;Thompson, Cynthia S. ;Ryu, Byung-Woo ;Selevonchick, Daniel P. ;Schaup, Henry W.

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 765 KB
• Volume: 9
• Category: Article
• ISSN: 0887-2082
• DOI: 10.1002/jbt.2570090608

✦ Synopsis

A dose-dependent reduction of hepatic pyruvate carboxylase levels and activity occurs in C57BL/6J male mice given 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) i.p. in a corn oil carrier. The dose range was from 1 to 75 pg/kg body weight and the analysis was done 8 days postinjection. At the maximum TCDD level investigated, we found a 10-fold reduction in pyruvate carboxylase activity. Furthermore, TCDD at a dose of 1 pg/kg body weight blocks corn oil induction of an increase in the amount of pyruvate carboxylase in liver protein extracts. At doses beyond those required to initiate a reduction in pyruvate carboxylase, lactate dehydrogenase isozyme patterns shift. This is accompanied by an increase in blood lactic acid levels. We propose that TCDD-mediated reduction in pyruvate carboxylase and lactate dehydrogenase isozyme shifts may represent a major component in TCDD toxicity.