Morphological aspects of transport of potassium ion in the marginal cell.
Structure and function of the marginal cell in the stria vascularis were studied by freeze-fracture, cytochemistry and immunohistochemistry with special regard to the ion transport of potassium. Freeze-fracture showed that marginal cells were connected by tight junctions beneath the scala media K(+)-NPPase cytochemistry showed that Na+, K(+)-ATPase was abundant on the basolateral infoldings of the marginal cell. Immunohistochemistry of a rat Isk protein, which has a property of a potassium channel, revealed that the rat Isk protein was localized at the endolymphatic surface of the marginal cell. These findings supported the 'one-pump' theory (Offner et al. Hear Res 1987; 29: 117-24).
Department of Otolaryngology, Osaka University Medical School, Japan.
M
M
Sakagami
K
K
Fukazawa
J
J
Murata
T
T
Matsunaga
D000818:Animals; D002462:Cell Membrane / Q000201:enzymology / Q000648:ultrastructure; D005614:Freeze Fracturing; D006168:Guinea Pigs; D007124:Immunoenzyme Techniques; D007365:Intercellular Junctions / Q000201:enzymology / Q000378:metabolism / Q000648:ultrastructure; D008565:Membrane Proteins / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D015221:Potassium Channels / Q000378:metabolism* / Q000648:ultrastructure*; D024642:Potassium Channels, Voltage-Gated; D051381:Rats; D017208:Rats, Wistar; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013316:Stria Vascularis / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism*
D008565:Membrane Proteins; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; C059983:potassium channel protein I(sk); D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium