Fig. 1.

Suppression of transepithelial potential (TEP) oscillations by cGMP. A: TEP recording of a Malpighian tubule (MT) bathed in standard bathing medium (SBM) and treated for 4.5 min with 1 mM cGMP as indicated by the bar. B and C: effect of 100 μM and 1 mM cGMP on the TEP coefficient of variation (CoV; B) and amplitude (C) in MTs bathed in SBM. TEP parameters were measured over 2-min windows ending with the addition of cGMP (pre-cGMP) and beginning 2 min after the addition of cGMP (post-cGMP); n = 7–8 MTs/condition. P values are from comparisons of pre-cGMP and post-cGMP values by paired t-test. Error bars indicate SD. n.s., Not significant.