Transient and persistent changes in rabbit blood vessels associated with maintained elevation in arterial pressure.
Arteries and veins of hypertensive rabbits were examined 8 weeks after partially constricting the abdominal aorta above both kidneys, and compared with those from sham-operated animals. Structural and functional changes in blood vessels after 2 weeks, when the arterial pressure first attained a new elevated level, have been described previously, and are now compared with changes 6 weeks later. The increase in blood vessel mass could be correlated with an increase in deoxyribonucleic acid (DNA) content. In contrast to the status at 2 weeks postoperatively, there was no increased uptake of 3H-thymidine, 3H-proline, or 3H-lysine at 2 months. Furthermore, at this time cell nuclei labeled with 3H-thymidine were infrequent. Some vessels showed evidence of change in the physical characteristics of their wall. Only minimal changes were observed in those parameters of adrenergic nerve function measured -- neuronal 3H-norepinephrine uptake and vessel wall catecholamine content -- that had been markedly changed at 2 weeks. The results of this work, together with those of other studies of this model, suggest two phases of response of the arterial wall to pressure rise: an initial dynamic proliferative cellular response mainly of vascular smooth muscle associated with changes in adrenergic neuronal parameters, and a subsequent equilibrium phase characterized by an increased number of smooth muscle cells, some changes in the extracellular components, and minimal changes in the adrenergic innervation.
D000818:Animals; D001012:Aorta, Abdominal / Q000473:pathology; D001158:Arteries / Q000473:pathology; D001808:Blood Vessels / Q000473:pathology* / Q000503:physiopathology; D006332:Cardiomegaly; D002455:Cell Division; D006973:Hypertension / Q000503:physiopathology*; D007668:Kidney / Q000473:pathology; D008026:Ligation; D009929:Organ Size; D014176:Protein Biosynthesis; D011817:Rabbits; D012083:Renin / Q000097:blood; D013564:Sympathetic Nervous System / Q000503:physiopathology; D013997:Time Factors; D014661:Vasoconstriction
D012083:Renin