Characteristics of ion transport across the isolated ciliary epithelium of the toad as studied by electrical measurements.

摘要: Abstract Potential difference (p.d.), short-circuit current (SCC) and electrical resistance ( R t ) across the isolated toad ciliary epithelium were measured under normal various experimental conditions including altered ionic composition of incubation medium, anoxia, presence 2,4-dinitrophenol (DNP), ouabain, thiocyanate (SCN − or theophylline. Under conditions, average values p.d., SCC 3·7 mV (epithelial side negative), 51 μA/cm 2 , 88·5 Ωcm respectively n = 29). In ion substitution experiments, increased in proportion to increase both Na + Cl concentration showed a saturable tendency at higher ranges. The elimination either from sides abolished p.d. almost completely. An K had stimulatory effect on lower concentrations, while it an inhibitory concentrations (Na -free)-Ringer reversed polarity Anoxia (bubbling with N ), 1 m -DNP -ouabain decreased when one drugs was applied but effects more potent drug epithelial side. On other hand 10 -SCN -theophylline caused significant reversible decrease only added It is concluded that electrogenic transport which absolutely requires indispensable transepithelial body.