The Vascular Ornithine Decarboxylase/Polyamine System in Deoxycorticosterone Acetate-Salt Hypertension
The present study was conducted to assess the time course of alterations in vascular polyamines and the associated changes in vascular structure and function in the deoxycorticosterone acetate-salt (DOCA-salt) rat. Cellular and molecular mechanisms involved in these alterations were examined in mesenteric resistance arteries at 1, 3, and 6 weeks of DOCA-salt treatment. Blood pressure increased progressively over the 6 week treatment period. Vascular polyamine contents and ornithine decarboxylase (ODC) activity were increased at all 3 time points in DOCA-salt rats. In contrast to ODC activity, ODC mRNA content was unaltered at 1 and 3 weeks and was significantly decreased at 6 weeks in DOCA-salt rats. Significant alterations in vascular structure and function accompanied the changes in the ODC/polyamine system. Coupled with previous reports from our laboratory, these data suggest that alterations in the ODC/polyamine system and the subsequent elevation in polyamines are required for the vascular changes observed in DOCA-salt hypertension.
KeywordsOrnithine Decarboxylase Polyamine Content Liquid Scintillation Detection Mesenteric Resistance Artery Mesenteric Vasculature
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