Abstract
Rats subjected to 10% O2 (hypoxic rats) for various periods and recovery regimens were compared with control animals with respect to pulmonary artery pressure (Ppa), right ventricular hypertrophy (RVH), and muscularisation of small pulmonary vessels. Mean Ppa was measured in anaesthetised animals spontaneously breathing air and rose from 16 mmHg in controls to 36 mmHg in rats exposed to hypoxia for three weeks. Ppa had returned to normal after 20 weeks' recovery in air. RVH regressed a little more quickly, but muscularisation of small pulmonary vessels. Mean Ppa was measured in anaesthetised animals spontaneously breathing air and rose from 16 mmHg in controls to 36 mmHg in rats exposed to hypoxia for three weeks. Ppa had returned to normal after 20 weeks' recovery in air. RVH regressed a little more quickly, but muscularisation of small pulmonary vessels was still apparent after 20 weeks. Some hypoxic rats were subjected to an intermittent normoxic recovery regimen for either 40 or 80 hours a week in air, the remainder in 10% O2. Some reduction in RVH probably occurred after six weeks on the 80-hour regimen, but there was no reduction in Ppa or muscularisation of small pulmonary vessels. These results suggest that the pulmonary hypertension of chronic alveolar hypoxia resolves very slowly and is probably related to structural changes in the pulmonary vessels. Their relevance to human cor pulmonale and intermittent long-term oxygen treatment for these patients is discussed.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Abraham A. S., Kay J. M., Cole R. B., Pincock A. C. Haemodynamic and pathological study of the effect of chronic hypoxia and subsequent recovery of the heart and pulmonary vasculature of the rat. Cardiovasc Res. 1971 Jan;5(1):95–102. doi: 10.1093/cvr/5.1.95. [DOI] [PubMed] [Google Scholar]
- Cryer A., Bartley W. The design and use of a hypoxic chamber for small animals. Lab Pract. 1974 Dec;23(12):713–715. [PubMed] [Google Scholar]
- Heath D., Edwards C., Winson M., Smith P. Effects on the right ventricle, pulmonary vasculature, and carotid bodies of the rat of exposure to, and recovery from, simulated high altitude. Thorax. 1973 Jan;28(1):24–28. doi: 10.1136/thx.28.1.24. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Herget J., Palecek F. Pulmonary arterial blood pressure in closed chest rats. Changes after catecholamines, histamine and serotonin. Arch Int Pharmacodyn Ther. 1972;198(1):107–117. [PubMed] [Google Scholar]
- Hunter C., Barer G. R., Shaw J. W., Clegg E. J. Growth of the heart and lungs in hypoxic rodents: a model of human hypoxic disease. Clin Sci Mol Med. 1974 Mar;46(3):375–391. doi: 10.1042/cs0460375. [DOI] [PubMed] [Google Scholar]
- Leach E., Howard P., Barer G. R. Resolution of hypoxic changes in the heart and pulmonary arterioles of rats during intermittent correction of hypoxia. Clin Sci Mol Med. 1977 Feb;52(2):153–162. doi: 10.1042/cs0520153. [DOI] [PubMed] [Google Scholar]
- McMurtry I. F., Reeves J. T., Will D. H., Grover R. F. Reduction of bovine pulmonary hypertension by normoxia, verapamil and hexoprenaline. Experientia. 1977 Sep 15;33(9):1192–1194. doi: 10.1007/BF01922322. [DOI] [PubMed] [Google Scholar]
- Ressl J., Urbanová D., Widimský J., Ostádal B., Pelouch V., Procházka J. Reversibility of pulmonary hypertension and right ventricular hypertrophy induced by intermittent high altitude hypoxia in rats. Respiration. 1974 Jan;31(1):38–46. doi: 10.1159/000193097. [DOI] [PubMed] [Google Scholar]
- Scott K. W. Quantitation of thick-walled peripheral lung vessels in chronic airways obstruction. Thorax. 1976 Jun;31(3):315–319. doi: 10.1136/thx.31.3.315. [DOI] [PMC free article] [PubMed] [Google Scholar]