Gap junction channels were reconstituted into unilamellar liposomes using connexin 32 gap junction protein immunoaffinity purified from rat liver. Vesicles containing open channels and close channels were separated by means of iso-osmolar sucrose density gradient sedimentation. The open channels formed in lipid vesicles were permeable to small communication dye molecule, lucifer yellow (M. W. 457, 1.2 nm) of which the hydrodynamic size is similar to pore size of gap junctions in vivo, but this passage failed when the large fluorescence dye molecule, rhodamine dextran was used, and thus indicates the presence of functional open gap junction channels in the vesicles. Furthermore the gap junctional communication modulator, $H^{+}$ ion and octanol reversibly closed the reconstituted open junctional channel and these gatings were detected in iso-osmolar sucrose density gradient.
