Different turnover of rat fetal and placental ornithine decarboxylases.
The half-lives of ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (SAMDC) have been studied in fetuses and placentas from 18-day-pregnant rats. While the turnover of fetal and placental SAMDC were slightly different (t1/2 = 38 and 75 min, respectively) the half-lives of fetal and placental ODC differed markedly. T1/2 of fetal ODC was 15 min, similar to other mammalian ODCs, but placental ODC showed a relatively high half-life, about 160 min. According to that, placental ODC was more resistant than the fetal enzyme to in vivo hyperthermic treatment (40 degrees C, 1 h). Our results suggest that the degradative mechanisms for ODC in rat placenta could be regulated differently to those in other mammalian tissues.
López-Ballester
J A
JA
Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Murcia, Spain.
Gómez-Skarmeta
J L
JL
Cremades
A
A
Peñafiel
R
R
D000818:Animals; D003513:Cycloheximide / Q000494:pharmacology; D004795:Enzyme Stability / Q000187:drug effects; D005260:Female; D005333:Fetus / Q000201:enzymology*; D006207:Half-Life; D007700:Kinetics; D009955:Ornithine Decarboxylase / Q000378:metabolism*; D010920:Placenta / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains
D003513:Cycloheximide; D009955:Ornithine Decarboxylase