Active and Passive Cation Transport and L Antigen Heterogeneity in Low Potassium Sheep Red Cells
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چکیده
I N T R O D U C T I O N I t is now well e s t a b l i s h e d t ha t act ive N a + K + t r a n s p o r t ( p u m p f lux) in lowp o t a s s i u m (LK) s h e e p r e d cells ( K e r r , 1937; Evans , 1954; T o s t e s o n a n d H o f f m a n , 1960) is s t i m u l a t e d s e v e r a l f o l d w h e n these cells a r e e x p o s e d to t he L a n t i s e r u m , wh ich r e c o g n i z e s spec i f ic m e m b r a n e s u r f a c e a n t i g e n s (El lory a n d T u c k e r , 1969; R a s m u s e n , 1969; L a u f et a l . , 1970). T h e ac t iva t ion o f N a ÷ K + p u m p f lux involves k ine t i c c h a n g e s r a t h e r t h a n an i n c r e a s e in t h e n u m b e r o f p u m p s p e r cell ( J o i n e r a n d L a u f , 1975, 1977). T h e k ine t ic c h a n g e s cons is t m a i n l y o f an i n c r e a s e in t he a f f i n i t y o f t he c y t o p l a s m i c a s p e c t o f t he Na+K + p u m p fo r THE JOURNAL OF GENERAL PHYSIOLOGY " VOLUME 70, 1977 " p a g e s 2 2 1 2 4 2 2 2 1 on M ay 4, 2017 D ow nladed fom Published August 1, 1977
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