[Effect of adaptation to high altitude hypoxia on the development of structural changes in the resistance vessels of the spontaneously hypertensive rat].

Adaptation to high altitude hypoxia prevents the development of arterial hypertension only in young spontaneously hypertensive rats (SHR) in the pre-hypertension stage. Adult SHR exposed to high altitude hypoxia showed no hypotensive effect. Judging by the experiments with extremities perfusion, the prophylactic effect of high altitude hypoxia in young SHR is associated with an increased number of resistant vessels. The increased ratio of the thickness of the vessel wall to the vascular lumen, however, remains unchanged probably due to the genetically determined development of hypertrophy of vascular smooth muscles.