Fig. 4. Reversibility and kinetics of nuclear swelling. (A) After swelling finished in a time (t_eq), the relative surface area expansion () could be reversed with addition of dextrans (50 mg/ml). Swollen nuclei are also significantly deflated by addition of 5% Triton X-100 detergent () as water and solutes flow through the perforated nucleus. The nuclei remain visibly intact, nonetheless. (B) Swelling (of four nuclei) shows an initial linear increase in with equilibration at t_eq=500 seconds. (C) Swelling was systematically reduced by addition of either 500 kDa dextran () or 500 kDa dextran sulfate (), but concentrations of dextrans >50 mg/ml do not compress nuclei relative to their original size.