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Z Detre

Publications and source records attributed to Z Detre.

24 records · Page 2Linked to original sources

The early arterial effects of renovascular hypertension in rats.

Experimental hypertension in rats increases vascular permeability to tracers such as Trypan blue or colloidal iron. The amount of tracer which enters the tissues examined : brain, skin and aortic wall is proportional to the damage of the vascular wall. The highest permeability increase was seen in the aortic wall, then in the skin. Brain vessels seem to be the most resistant to permeability increase induced by experimental hypertension.

Animals↗

Aortic response to renovascular hypertension.

In the early phase of malignant renal hypertension induced by aortic ligature, a transient activation of transmural aortic permeability is observed. The transmural permeability shows its maximum during the first week of hypertension returning in the third week to normal or even subnormal values, whereas the blood pressure is still rising. The permeability disturbance precedes the structural transformation of the arterial wall. Although the aortic segments above and below the ligature are exposed to different blood pressure and hemodynamic stresses their patterns of permeability disturbance are the same. If the kidney below the aortic ligature is removed no permeability disturbance can be observed. Aortic wall PGI2-formation both above and below the ligature is elevated in the first phase of hypertension. The PGI2-synthesis returns to normal values during the 5th week. Our data suggest that in the early phase of renovascular hypertension there is an increased aortic antiaggregatory activity and that PGI2 is probably not the compound responsible for increased transmural permeability. Moreover, the blood pressure and the hemodynamic forces have no decisive importance in the induction of the aortic transmural permeability disturbance.

Animals↗

[Variation in vascular permeability in the initial phase of experimental hypertension in the rat].

A transient increase of vascular permeability was observed during the initial phase of renovascular experimental hypertension. The intensity of the permeability-increase varied according to the vascular regions considered: the strongest increase was observed in the aorta-wall; next came the skin, and the smallest increase occurred in the brain. The highest permeability values were observed on the 4th day after induction of hypertension in the brain and in the skin, and on the 7th day only in the aorta. On the 14th day of hypertension, the permeability was back to normal in all the 3 vascular regions studied. Anthocyanoside treatment diminished the permeability increase induced by hypertension. The strongest protective action was observed in the brain, next in the aorta, and it was the weakest in the skin.

Animals↗

Permeability of the post-ischemic rat aorta.

The time course of the vascular permeability disorder following upon acute hypoxia and the fate of plasma substances entering the vessel wall in consequence of increased permeability were studied on the rat abdominal aorta rendered hypoxic for one hour by double ligature and recirculated for periods ranging from one hour to 30 days. The distribution and quantity of mural plasma inhibition were determined histochemically by means of a colloidal iron tracer and Prussian blue reaction and by photometric analysis, respectively. Plasma imbibition reached its maximum after recirculation for 24 to 48 hours and fell to an almost normal level after 10 days. Administration of the colloidal iron tracer on the second day of recirculation, when the permeability disorder was at its peak, showed plasma imbibition in every layer of the vessel wall. At seven days it was restricted to the outer third of the media and the adventitia. The endothelium is acting as the main barrier to mural plasma imbibition and in the case of a permeability disorder only the elastic lamellae constitute a temporary mechanical obstacle to the ingression of plasma.

Animals↗