Induction of Spermidine/Spermine N¹-Acetyltransferase by Parathyroid Hormone in Rabbit Costal Chondrocytes in Culture

抄録

Parathyroid hormone (PTH) increased the activity of spermidine/spermine N¹-acetyltransferase, a rate-limiting enzyme of polyamine biodegradation, in rabbit costal chondrocytes in culture. The enzyme activity increased in a dose-dependent manner after addition of PTH to the culture, reaching a maximum at 8 h. The increase in the enzyme activity was abolished by cycloheximide or actinomycin D. Dibutyryl cyclic AMP also induced the acetyltransferase to some extent. These results suggest that the induction of spermidine/spermine N¹-acetyltransferase by PTH may play some significant role in the expression of the differentiated pheno-type of chondrocytes.