A complex network of “snake-like tubules” revealed by the NADPase cytochemical reaction in the acinar cell of pancreas

Abstract

We have recently described the ultrastructural localization of NADPase activity in the exocrine pancreas of rat. The enzyme was found in the intermediate saccules of the Golgi apparatus, in dense bodies and lysosomes but was absent from zymogen granules. A very intense reaction was noticed in a peculiar structure which was termed “Snake-Like Tubule” (SLT). The purposes of the present study were firstly to delineate SLT distribution in the acinar cell and secondly to define any possible relationship or association with other cellular organelles.NADPase cytochemical reaction was performed on the pancreas of adult Sprague Dawley rats. Small lobules were excised and fixed for 50 min, at 4°C, in 2% glutaraldehyde buffered with 0.1M cacodylate at pH 7.2. Lobules were rinsed several times with the same buffer containing 570 sucrose and cut with a Mcllwayn tissue chopper. Sections were washed several times with buffer and incubated for 2 hr at 37°C in the following medium: 4mM NADPH; 40mM sodium acetate buffer, pH 5.0; 4mM lead acetate and 5% sucrose.