Fig. 1.
Effect of spermine (SPM) on Cx43 gap junction channels. (a) Examples of junctional current (Ij) records from HeLaCx43-EGFP cell pairs in response to a repeated step-ramp-step protocol shown in (b). The presence of SPM in the pipette solution caused an increase, whereas the absence of SPM produced a decrease in Ij over time. (b) Voltage (Vj) protocol used to study Ij changes over time. (c) Summarized data after 10 min of recording in the presence or absence of 0.5 mM SPM in the pipette solution. Gap junctional conductance was calculated and normalized. Error bars represent SEM. *Significant difference (P<0.05, n=9 in each group). (d) Averaged junctional conductance (gj) measurements in Novikoff cell pairs using different intracellular concentrations of SPM: no SPM, 1 mM SPM, 5 mM SPM, and 10 mM SPM. (e) Summarized data of experiments shown in (d) at 10 min of the recordings. Error bars represent SEM. *Significant difference between groups (P<0.05, n=5 in each group).