Effect of proteases and other treatments on the proliferative assembly of tight junction strands in the rat prostate tissue.
As already observed with the freeze-fracture technique by Kachar and Pinto da Silva (1981) incubation of excised rat ventral prostate tissue at 37 degrees C results in proliferation of tight junction strands over the lateral membranes of the epithelial cells, an effect not occurring after incubation at 4 degrees C. Our investigations have shown that a pretreatment with protease inhibitor Contrykal at 4 degrees C suppresses the proliferation of tight junction strands at 37 degrees C. On the other hand the added proteases trypsin and pronase induce the proliferation already at 4 degrees C. The effect was lowered by higher concentrations of pronase. Incubation with solutions of the non-ionic detergent Triton X-100 at 4 degrees C could also induce tight junction proliferation, whereas this effect was nearly absent after an incubation at 4 degrees C with a hyperosmotic solution of arabinose and with 50% acetone. No relation was found between proliferation of tight junction strands and cluster formation of intramembraneous particles. In conclusion of the results a small protein or a peptide resembling fusions proteins is assumed as trigger for formation of tight junction strands, acting by destabilization of the bilayer arrangement of membrane lipids.
Meyer
H W
HW
Department of Electron Microscopy, Friedrich Schiller University Jena, Medical School, DDR.
Freytag
C
C
Freytag
T
T
Richter
W
W
D000096:Acetone / Q000494:pharmacology; D000818:Animals; D001089:Arabinose / Q000494:pharmacology; D003902:Detergents / Q000494:pharmacology; D005614:Freeze Fracturing; D007365:Intercellular Junctions / Q000187:drug effects / Q000648:ultrastructure*; D008297:Male; D008854:Microscopy, Electron; D017830:Octoxynol; D011092:Polyethylene Glycols / Q000494:pharmacology; D011402:Pronase / Q000494:pharmacology*; D011467:Prostate / Q000187:drug effects / Q000648:ultrastructure*; D051381:Rats; D014357:Trypsin / Q000494:pharmacology*
D003902:Detergents; D000096:Acetone; D011092:Polyethylene Glycols; D017830:Octoxynol; D001089:Arabinose; D014357:Trypsin; D011402:Pronase