Association of malachite green-positive material with heparan sulfate proteoglycan double tracks in basement membrane of mouse kidney tubules.

Abstract

The presence of lipids in the basement membrane of the mouse kidney tubules was examined by histochemical staining with malachite green. Pieces of mouse kidney cortex were immersed in a fuative containing 3% glutaraldehyde and 0.1% malachite green in 0.067 M sodium cacodylate buffer, pH 6.8, for 18 hr at 4°C. Control tissue was fued in the same way except that no malachite green was added to the fuative. The tissue pieces were ayoprotected, frozen in Freon 22, and subjected to freeze-substitution in dry acetone containing 1% @Or. Thin sections of Epon-embedded specimens were observed by electron microscopy at fmt without uranyl-lead counterstaining. The basement membrane of