Research Article

Potassium Current Is Not Affected by Long-Term Exposure to Ghrelin or GHRP-6 in Somatotropes GC Cells

Figure 7

The transient potassium current ( ) in the cellular line of rat GC somatotropes under control conditions and treated with GHRP-6. (a) and (b): family of representative traces of the current of a control cell and a cell treated with GHRP-6 (100 nM) for 96 h. The current was evoked by means of a protocol of depolarizing pulses, starting from a holding potential of −80 mV. Thereafter, the cell was hyperpolarized at −130 mV for 500 ms, and then depolarized from −80 to 60 mV with increases of 10 mV lasting 1.5 s; the recording protocol is shown in the lower portion of panel (b). The external recording solution for potassium currents contained Tetraethylammonium 30 mM. (c) and (d): Current-voltage relationship and density of current-voltage, respectively, for each one of the experimental conditions; the peak current was measured in the first 50 ms of the trace. The number of cells analyzed in control condition was 16, with a capacitance value of ; 14 cells that had been treated with GHRP-6 100 nM for 96 h were also analyzed, their capacitance value being .
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