Fig. 4. Necturus erythrocytes loaded with fluo-4 (10 µM), bathed in a
hypotonic (0.5x) Ringer solution and exposed to FITC filtered UV light.
(A,C) Hexokinase (2.5 U/ml, n=6) and suramin (100 µM,
n=6) inhibited the level of fluorescence normally observed following
hypotonic shock. (B,D) Addition of A23187 (0.5 µm0 to the extracellular
medium increased fluorescence in the presence of hexokinase (n=6) or
suramin (n=6).