Evidence for Na+/H+ exchange in vertebrate rod photoreceptors.
In this paper, we have documented our investigation of pH regulation in the rod photoreceptor of the toad, Bufo marinus. Unlike other neural tissues, the retina depends upon aerobic glycolysis to meet its energy requirements. A consequence of its reliance on glycolysis is a large metabolic production of protons (H+) which must be extruded by pH regulating mechanisms. Based on the work of previous authors, we propose that rods share these same characteristics with whole retina. Our results in rods are consistent with the hypothesis that under nominally bicarbonate-free conditions, an amiloride-sensitive Na+/H+ exchanger contributes to pH regulation in this cell.
Katz
B J
BJ
Medical Scholars Program, University of Illinois, Urbana-Champaign 61801.
Oakley
B
B
D000584:Amiloride / Q000494:pharmacology; D000643:Ammonium Chloride / Q000494:pharmacology; D000818:Animals; D002024:Bufo marinus; D002118:Calcium / Q000378:metabolism; D002352:Carrier Proteins / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D010775:Photic Stimulation; D010786:Photoreceptor Cells / Q000187:drug effects / Q000378:metabolism*; D011522:Protons; D012964:Sodium / Q000378:metabolism*; D017923:Sodium-Hydrogen Exchangers
D002352:Carrier Proteins; D011522:Protons; D017923:Sodium-Hydrogen Exchangers; D000643:Ammonium Chloride; D000584:Amiloride; D012964:Sodium; D002118:Calcium