THE DELAYED BASOLATERAL MEMBRANE HYPERPOLARIZATION OF THE BOVINE RETINAL-PIGMENT EPITHELIUM - MECHANISM OF GENERATION

被引:32
作者
BIALEK, S
JOSEPH, DP
MILLER, SS
机构
[1] UNIV CALIF BERKELEY,SCH OPTOMETRY,BERKELEY,CA 94720
[2] UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,DIV CELL & DEV BIOL,BERKELEY,CA 94720
来源
JOURNAL OF PHYSIOLOGY-LONDON | 1995年 / 484卷 / 01期
关键词
D O I
10.1113/jphysiol.1995.sp020647
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
1. Conventional and ion-selective double-barrelled microelectrodes were used in an in vitro preparation of bovine retinal pigment epithelium (RPE)-choroid to measure the changes in membrane voltage, resistance and intracellular Cl- activity (a(Cl)(i)) produced by small, physiological changes in extracellular potassium concentration ([K+](0)). These apical [K+](0) changes approximate those produced in the extracellular (subretinal) space between the photoreceptors and the RPE following transitions between light and dark. 2. Changing apical [K+](0) from 5 to 2 mM in vitro elicited membrane voltage responses with three distinct phases. The first phase was generated by an apical membrane hyperpolarization, followed by a (delayed) basolateral membrane hyperpolarization (DBMH); the third phase was an apical membrane depolarization. The present experiments focus on the membrane and cellular mechanisms that generate phase 2 of the response, the DBMH. 3. The DBMH was abolished in the presence of apical bumetanide (100 mu M); this response was completely restored after bumetanide removal. 4. Reducing apical [K+](0), adding apical bumetanide (500 mM), or removing apical Cl- decreased a(Cl)(i) by 25 +/- 6 (n = 8), 28 +/- 1 (n = 2) and 26 +/- 5 mM (n = 3), respectively; adding 100 mu M apical bumetanide decreased a(Cl)(i) by 12 +/- 2 mM (n = 3). Adding apical bumetanide or removing apical bath Cl- hyperpolarized the basolateral membrane and decreased the apparent basolateral membrane conductance (G(B)). 5. DIDS (4,4'-diisothiocyanostilbene-2,2'-disulphonic acid) blocked the RPE basolateral membrane Cl- conductance and inhibited the DBMH and the basolateral membrane hyperpolarization produced by apical bumetanide addition or by removal of apical Cl-0(-). The present results show that the DBMH is caused by Delta[K](0)-induced inhibition of the apical membrane Na+-K+-2Cl(-) cotransporter; the subsequent decrease in a(Cl)(i) generated a hyperpolarization at the basolateral membrane Cl- channel.
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页码:53 / 67
页数:15
相关论文
共 41 条
[31]   EFFECT OF INTRACELLULAR POTASSIUM UPON THE ELECTROGENIC PUMP OF FROG RETINAL-PIGMENT EPITHELIUM [J].
OAKLEY, B ;
MILLER, SS ;
STEINBERG, RH .
JOURNAL OF MEMBRANE BIOLOGY, 1978, 44 (3-4) :281-307
[32]  
QUINN RH, 1992, INVEST OPHTH VIS SCI, V33, P3513
[33]  
RINK TJ, 1982, J CELL BIOL, V96, P189
[34]   REACCUMULATION OF [K+]O IN THE TOAD RETINA DURING MAINTAINED ILLUMINATION [J].
SHIMAZAKI, H ;
OAKLEY, B .
JOURNAL OF GENERAL PHYSIOLOGY, 1984, 84 (03) :475-504
[35]   INTRACELLULAR RESPONSES TO LIGHT FROM CAT PIGMENT EPITHELIUM - ORIGIN OF ELECTRORETINOGRAM C-WAVE [J].
STEINBERG, RH ;
SCHMIDT, R ;
BROWN, KT .
NATURE, 1970, 227 (5259) :728-+
[36]  
Steinberg RH, 1985, PROGR RETINAL RES, V4, P33
[37]   REGULATION OF CL- CHANNELS IN NORMAL AND CYSTIC-FIBROSIS AIRWAY EPITHELIAL-CELLS BY EXTRACELLULAR ATP [J].
STUTTS, MJ ;
CHINET, TC ;
MASON, SJ ;
FULLTON, JM ;
CLARKE, LL ;
BOUCHER, RC .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1992, 89 (05) :1621-1625
[38]   INTRA-RETINAL RECORDINGS OF SLOW ELECTRICAL RESPONSES TO STEADY ILLUMINATION IN MONKEY - ISOLATION OF RECEPTOR RESPONSES AND THE ORIGIN OF THE LIGHT PEAK [J].
VALETON, JM ;
VANNORREN, D .
VISION RESEARCH, 1982, 22 (03) :393-399
[39]  
WEAST RC, 1978, CRC HDB CHEM PHYSICS, pD153
[40]   FAST AND SLOW OSCILLATIONS OF THE ELECTRO-OCULOGRAM IN BESTS MACULAR DYSTROPHY AND RETINITIS PIGMENTOSA [J].
WELEBER, RG .
ARCHIVES OF OPHTHALMOLOGY, 1989, 107 (04) :530-537