Recent Advances in Nuclear Electrophysiology - Fig. 4 - Smallest

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Fig. 4. Computed values for the resistance contributed by the NE and for the shunt resistance using the NHT model. (a) Plot of expected values for the resistance of the NE caps, R_NE-caps, with NPC conductance, g_NPC, of 500 pS and with density of ion conducting NPCs set to 10 NPC.mm^-2. (b) Plot of shunt resistance, R_shunt, due to the leak of electrolyte between the NE and the wall of the NHT tubing (gap length, L_gap, of 100 mm; gap radius, r_gap, 100 mm) and between the NE and the tip of the patch-clamp pipette (L_gap = 0.1 mm, r_gap =1 mm). The resistivity, r, was assumed to be 100 W.cm (conductivity= 10 mS.cm^-1). The values of gap width, w, used were between 1.0 and 10^-4 mm. For NHT, R_shunt goes between 1.6 MW and 15.9 GW. For patch-clamp, R_shunt goes between 318.3 kW and 1.59 GW. Therefore, from these models one should expect that the NHT method provided better seal than patch-clamp. However, this is not supported by the experimental observations.