Ultrastructural changes and cell membrane permeability defects demonstrated with colloidal lanthanum in anoxic isolated perfused rat hearts

1983 ◽  
Vol 15 ◽  
pp. 77-77
Author(s):  
Jung Yeh Chih ◽  
Y.S. Han
Weed Science ◽  
1989 ◽  
Vol 37 (1) ◽  
pp. 98-106 ◽  
Author(s):  
Kiet M. Thai ◽  
Sakti Jana ◽  
Larry C. Fowke

Effects of difenzoquat on wild oats grown under controlled environmental conditions were studied. Seedling height and fresh weight were significantly reduced 5 days after postemergence treatment. Dose-dependent increase in cell membrane permeability was detected after a 12-h exposure to the herbicide. Scanning electron micrographs showed normal leaf hairs and cuticular wax but swollen guard cells 10 days after treatment. Ultrastructural changes occurred before the visible symptoms. The primary effect of difenzoquat appears to be the disruption of the tonoplast and plasmalemma. The tonoplast showed greater damage than the plasmalemma. Secondary effects included damage to mitochondria and chloroplasts. Mitochondria were swollen and often ruptured, but the effect did not increase with the duration of exposure. Chloroplasts became spherical in shape, and their contents were also affected. The changes included: accumulation and then disappearance of starch granules, swelling of frets, fusion of granal thylakoids, detachment and then rupture of the outer membrane of the envelope, and clumping of ribosomes. By contrast, natural senescence caused greater injury of the plasmalemma than the tonoplast, a marked increase in size of plastoglobuli, and loss of starch grains without early accumulation.


Author(s):  
M. Ashraf ◽  
L. Landa ◽  
L. Nimmo ◽  
C. M. Bloor

Following coronary artery occlusion, the myocardial cells lose intracellular enzymes that appear in the serum 3 hrs later. By this time the cells in the ischemic zone have already undergone irreversible changes, and the cell membrane permeability is variably altered in the ischemic cells. At certain stages or intervals the cell membrane changes, allowing release of cytoplasmic enzymes. To correlate the changes in cell membrane permeability with the enzyme release, we used colloidal lanthanum (La+++) as a histological permeability marker in the isolated perfused hearts. The hearts removed from sprague-Dawley rats were perfused with standard Krebs-Henseleit medium gassed with 95% O2 + 5% CO2. The hypoxic medium contained mannitol instead of dextrose and was bubbled with 95% N2 + 5% CO2. The final osmolarity of the medium was 295 M osmol, pH 7. 4.


2015 ◽  
Vol 25 (17) ◽  
pp. 3610-3615 ◽  
Author(s):  
Junsuke Hayashi ◽  
Tomoko Hamada ◽  
Ikumi Sasaki ◽  
Osamu Nakagawa ◽  
Shun-ichi Wada ◽  
...  

1974 ◽  
Vol 64 (6) ◽  
pp. 706-729 ◽  
Author(s):  
W. R. Redwood ◽  
E. Rall ◽  
W. Perl

The permeability coefficients of dog red cell membrane to tritiated water and to a series of[14C]amides have been deduced from bulk diffusion measurements through a "tissue" composed of packed red cells. Red cells were packed by centrifugation inside polyethylene tubing. The red cell column was pulsed at one end with radiolabeled solute and diffusion was allowed to proceed for several hours. The distribution of radioactivity along the red cell column was measured by sequential slicing and counting, and the diffusion coefficient was determined by a simple plotting technique, assuming a one-dimensional diffusional model. In order to derive the red cell membrane permeability coefficient from the bulk diffusion coefficient, the red cells were assumed to be packed in a regular manner approximating closely spaced parallelopipeds. The local steady-state diffusional flux was idealized as a one-dimensional intracellular pathway in parallel with a one-dimensional extracellular pathway with solute exchange occurring within the series pathway and between the pathways. The diffusion coefficients in the intracellular and extracellular pathways were estimated from bulk diffusion measurements through concentrated hemoglobin solutions and plasma, respectively; while the volume of the extracellular pathway was determined using radiolabeled sucrose. The membrane permeability coefficients were in satisfactory agreement with the data of Sha'afi, R. I., C. M. Gary-Bobo, and A. K. Solomon (1971. J. Gen. Physiol. 58:238) obtained by a rapid-reaction technique. The method is simple and particularly well suited for rapidly permeating solutes.


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