A chloride conductance exhibiting bicarbonate conductivity in renal inner medullary collecting duct cells

Rok, strany: 2014, 321 - 334

The anion conductance in primary cultures of rat inner medullary collecting duct cells was studied using perforated-patch whole-cell clamp technique. Depolarizations above 0 mv induced an outward anionic current with a time-dependent activation (Iovt) exhibiting a similar conductivity to Cl^- and HCO3^-. Iovt showed half-maximal activation around 32 mV with a slope factor of 23 mV, and showed a voltage-dependent activation time course that was well fitted by a sum of two exponential functions. Iovt was potentiated when external pH or external Ca²⁺ was increased and was blocked by external DIDS, DPC and furosemide. These characteristics of Iovt resemble that of the ClC-K1 channels mediated currents; however, anion substitution studies showed that Iovt exhibits a Br^- > Cl^- > I^- > NO3^- conductivity sequence, different from that observed in the ClC-K1 channels-mediated conductance. We suggest that, in inner medullary collecting duct cells, ClC-K channels of an unidentified type give rise to this Cl^- and HCO3^- conductance. This is the first study of a channel-mediated HCO3^- current in kidney tubular cells.

ISO 690:

Bolívar, J., Lara-Figueroa, C., Martínez- Mayorquin, R., Monroy-Romero, F., Arenas, G. 2014. A chloride conductance exhibiting bicarbonate conductivity in renal inner medullary collecting duct cells. In General Physiology and Biophysics, vol. 33, no.3, pp. 321-334. 0231-5882.

APA:

Bolívar, J., Lara-Figueroa, C., Martínez- Mayorquin, R., Monroy-Romero, F., Arenas, G. (2014). A chloride conductance exhibiting bicarbonate conductivity in renal inner medullary collecting duct cells. General Physiology and Biophysics, 33(3), 321-334. 0231-5882.