Relatively little is known about how 15-PGDH activity is regulated. Changes in 15-PGDH activity have been reported in response to physiological changes brought about by aging, pregnancy, hormonal changes, hypertension and smoking. In addition a large number of drugs have been shown to affect 15-PGDH activity both in vivo and in vitro. The availability of the 15-PGDH cDNA will be a valuable tool for studying how this enzyme is regulated. Isolation of the genomic DNA with its promoter regions has not yet been reported.