Ultrastructural changes in rat lung arterioles in conditions of altered permeability

Abstract

By means of the colloidal carbon technique and injection of a barium-gelatin mixture into the pulmonary artery, the ultrastructure of lung arterioles in a state of increased permeability has been studied. In certain conditions pulmonary arteriolar permeability changes are frequent and the carbon particles adhere to the endothelium. Leakage of carbon into the interstitial space is observed only rarely. It is concluded that the pulmonary and systemic vessels have different patterns of response to altered permeability.

Comparative study of the ultrastructural alterations in the pulmonary vessels of rats treated with alphanaphthylthiourea (ANTU) and ammonium sulphate

“…In our experience arterial structures were as involved in the pathological process as the venular ones and only a painstaking quantitative study would decide which structure is more affected by ANTU. This participation of arterioles in permeability changes seems to be characteristic of the pulmonary circulation (Bohm, Machado and Padovan, 1977).…”

“…12, 13 and 14). Discontinuity of the endothelial layer was not rare but leakage of carbon was seldom seen, although it has been recorded even in arterial structures (Bohm, Machado and Padovan, 1977). In larger vessels alterations are not common and if present they consist of thrombosis.…”