INCREASED EXPRESSION OF SULFATED GLYCOPROTEIN-2 AND DNA FRAGMENTATIONIN THE PANCREAS OF COPPER-DEFICIENT RATS

Recent morphological studies from our laboratory have shown that coppe r deficiency-induced pancreatic involution in rats is secondary to apo ptosis (M. S. Rao, A. V. Yeldandi, V. Subbarao, and J. K. Reddy, 1993, Am. J. Pathol. 142, 1952-1957). To corroborate the morphological find ings, we have examined pancreases from copper-deficient rats for expre ssion of sulfated glycoprotein-2 (SGP-2) mRNA and DNA fragmentation, w hich are considered as specific markers of apoptosis. Agarose gel elec trophoresis of the DNA extracted from pancreas of rats maintained on c opper deficient diet (CUDD) for 5 and 7 weeks showed characteristic '' ladder'' pattern, whereas DNA from control rats and rats maintained on CUDD for 3 weeks showed no fragmentation. These findings correlated w ell with the histological changes. Northern blot analysis of total RNA revealed a marked increase in the expression of SGP-2 mRNA at 5 weeks followed by a gradual decrease at 6 and 7 weeks. These results furthe r support that the mechanism of copper deficiency-induced pancreatic i nvolution is through apoptosis. (C) 1994 Academic Press, Inc.