ausblenden:
Schlagwörter:
In situ recordings;
Inward rectifer;
K+ current;
Glial cells;
Folliculo-stellate cells;
Intermediate lobe;
Xenopus laevis
Zusammenfassung:
In situ whole cell voltage clamp recordings of presumed folliculo−stellate cells were made in the intermediate lobe of the clawed toad Xenopus laevis. Lucifer Yellow fillings revealed, in addition to the small, spherical melanotropes, a population of larger cells with many processes that were, to a limited extent, dye−coupled and are assumed to be folliculo−stellate cells. The presumed folliculo−stellate cells differed strongly from the melanotropes in electrophysiological properties. The cells had a membrane resistance of < 600 M ω (at −100 to −80 mV) and a membrane potential of ca. −90 mV, close to the equilibrium potential for K+. At potentials of > or = −20 mV, most of the cells displayed a rapidly activating and slowly inactivating outward K+ current. In all cells, hyperpolarizing pulses to < or = −100 mV activated an inward rectifying K+ current