DNA template activity in the arterial wall of hypertensive rabbits

With a new method employing acridine organe (AO) as an ultracytochemical probe DNA template activity could be visualized within cell nuclei of the thoracic aortic wall of rabbits. After experimentally produced chronic renal hypertension nuclei with a relatively high number of AO chromatin interaction products were found in the endothelium, in the intimal region, in the outer third of the media, and in the adventiia indicating increased DNA template activity. This representative distribution pattern of DNA template activity was not found in comparable regions of the thoracic aorta of normotensive rabbits. The results are consistent with the current concept that cellular response to environmental stimuli occurs via activation of previously repressed genes.