TY - JOUR
T1 - Characterization of active and passive na+ and k+ transport in normal rat Lens by the short-circuiting technique
AU - Estapé, Estela S.
AU - Rodriguez-Sargent, Carmen
AU - Candia, Oscar A.
N1 - Funding Information:
A-S This work was supported by Merit Review Grants, Dept. Veterans Affairs; American Heart Assoc., P.R. Chapter; National Institutes of Health: RR-03051, Q4-08102-19, EY00160, EY01867.
PY - 1992
Y1 - 1992
N2 - An initial characterization of the lenticular ionic permeabilities of the isolated Sprague-Dawley rat lens utilizing short-circuiting techniques was carried out to provide the basis for further studies of mechanisms underlying cataractogenesis associated with salt-sensitive genetic hypertension in the rat. Both active and passive Na+ and Kf transport were evaluated by varying ionic concentrations in the bathing solutions facing the anterior and posterior sides of the lens, as well as by the addition of BaCb and ouabain. In general, the ionic permeabilities and transport properties of the rat lens are qualitatively similar to those previously described in other species. Ionic replacement studies showed the presence of Naf and K+ channels at both surfaces of the lens, with the anterior side K+ conductance being larger than the posterior. In contrast, Na+ conductance was similar at both lens surfaces. The effects of ouabain confirmed the presence of the Na+ -K+ -ATPase at the lens epithelium, while the effects of serial addition of BaCh and ouabain suggested that the contribution of Kf diffusion to the short-circuit current may be considerably greater than the electrogenic component of the Na+ -K+ pump.
AB - An initial characterization of the lenticular ionic permeabilities of the isolated Sprague-Dawley rat lens utilizing short-circuiting techniques was carried out to provide the basis for further studies of mechanisms underlying cataractogenesis associated with salt-sensitive genetic hypertension in the rat. Both active and passive Na+ and Kf transport were evaluated by varying ionic concentrations in the bathing solutions facing the anterior and posterior sides of the lens, as well as by the addition of BaCb and ouabain. In general, the ionic permeabilities and transport properties of the rat lens are qualitatively similar to those previously described in other species. Ionic replacement studies showed the presence of Naf and K+ channels at both surfaces of the lens, with the anterior side K+ conductance being larger than the posterior. In contrast, Na+ conductance was similar at both lens surfaces. The effects of ouabain confirmed the presence of the Na+ -K+ -ATPase at the lens epithelium, while the effects of serial addition of BaCh and ouabain suggested that the contribution of Kf diffusion to the short-circuit current may be considerably greater than the electrogenic component of the Na+ -K+ pump.
UR - http://www.scopus.com/inward/record.url?scp=0026560860&partnerID=8YFLogxK
U2 - 10.3109/02713689209000070
DO - 10.3109/02713689209000070
M3 - Article
C2 - 1315240
AN - SCOPUS:0026560860
SN - 0271-3683
VL - 11
SP - 189
EP - 193
JO - Current Eye Research
JF - Current Eye Research
IS - 2
ER -