Licht-und elektronenmikroskopische Untersuchungen am proximalen Tubuluskonvolut der Rattenniere nach intraluminaler Ölinjektion

Summary

Light- and electronmicroscopic evaluation of proximal convolutions of the rat kidney were made following injection with either mineral oil or castor oil. The following observations were made:

• 1. Injection of mineral oil does not result in a complete blockade of the tubular lumen and leads to morphological lesions of epithelial cells.

• 2. Injection of the more viscous castor oil, in contrast, leads to a dilatation of the tubular lumen and a compression of the brush border of proximal tubular cells. Thus a better blockade of longitudinal flow is achieved. A toxic effect of castor oil on the tubular epithelium could not be detected. Mechanical lesions, similar to those observed after mineral oil injection, were less frequent. They consisted in a penetration of oil into the cells, perhaps as consequence of the tubular dilatation.

• 3. In oil-injected proximal tubular segments the following cytologic phenomena were observed:

• a) a cessation of the normal pinocytosis, which is induced in the presence of tubular fluid,

• b) simultaneously the “large resorption vacuoles” disappear, indicating that they originate from confluence of pinocytotic vesicles,

• c) in dilated tubules protein resorption vacuoles are found to have ruptured towards the tubular lumen suggesting a high hydrostatic pressure within the vacuoles.