NaCl or KCl in hypotonic buffer - (Jan/08/2010 )

Hi, I started to isolate lysates from cyto and nuc. separately, when I incubated my cell pellets in hypotonic buffer containing 10mM NaCl, I had a few pre-mature nuclear lysis, the entire lysate became very viscous. But when I replace NaCl with KCl, it seemed to cure this problem, the nuclei remained intact. Does anyone know why this happened? THanks!!

TFC

I think its energetics. Remember the sod/pot pump? Its net effect is more sodium outside and less pot inside. If you have NaCl outside, the cell finds it very very hard to pump Na+, ultimately causing lysis due to hypotonicity. But by adding K+ you are helping the pump, resulting in happy cells. I'm just guessing.