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Three different Cl- channels in the bovine ciliary epithelium activated by hypotonic stress

, : Three different Cl- channels in the bovine ciliary epithelium activated by hypotonic stress. Journal of Physiology 499: 379-389

1. Hypotonic solution induced transient Cl- channel activity in both pigmented and non-pigmented ciliary epithelial cells in cell-attached patches. 2. The activation time constants for these currents were 63 and 97 s for non-pigmented and pigmented ciliary epithelial (NPCE and PCE) cells, respectively. The currents inactivated during the exposure to hypotonic solution with time constants of 59 and 304 s for NPCE and PCE cells, respectively. 3. Single channel analysis revealed the presence of a low-conductance Cl- channel in both the NPCE (7.3 +/- 0.4 pS) and PCE (8.6 +/- 0.9 pS) cells. In addition, an intermediate-conductance (18.8 pS) channel was found alone in the NPCE cells and a maxi Cl- channel (105 pS) was found in the PCE cells. The similarities between the 18.8 pS Cl- channel and the volume-activated organic osmolyte-anion channel (VSOAC) are discussed. 4. The hypotonic activation of all three Cl- channels was prevented by the inclusion of 100 microM 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB) in the patch pipette. 5. Inclusion of tamoxifen in the patch pipette inhibited only the intermediate-conductance channel in the NPCE cells. This is consistent with the identification of the intermediate 18 pS Cl- channel, found only in NPCE cells, as VSOAC. 6. Negative pressure also evoked single Cl- channel activity but the activation kinetics were quite different, suggesting that, even if the channels are the same, the second messenger pathways involved are different. 7. The activation/inactivation kinetics of these Cl- channels correlate well with the time course of regulatory volume decrease (RVD) in these cells, suggesting that these channels may well participate in the process of RVD. 8. The asymmetrical distribution of Cl- channels in the ciliary epithelium may be significant for aqueous humour secretion. For instance, the presence of the VSOAC-like channel in the NPCE cells may allow one-way traffic of anions and organic osmolytes into the eye and, if these solutes were loaded by the PCE cells, then a vectorial flow from the blood into the eye would occur.


PMID: 9080368

DOI: 10.1113/jphysiol.1997.sp021935

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Spasskii, A.A., 1984: The taxonomy of the composite genus Cotugnia (Cestoda: Davaineidae). Two new genera are erected for species of Cotugnia with a double complement of sex organs. Rostelugnia n.g. (type species R. polyacantha n.comb. for C. polyacantha) includes species parasitic in pigeons. It is characterized by a short and wide ros...

Dolla, A.; Guerlesquin, F.; Bruschi, M.; Haser, R., 1991: Ferredoxin electron transfer site on cytochrome c3. Structural hypothesis of an intramolecular electron transfer pathway within a tetra-heme cytochrome. To specify electron exchanges involving Desulfovibrio desulfuricans Norway tetra-heme cytochrome c3, the chemical modification of arginine 73 residue, was performed. Biochemical and biophysical studies have shown that the modified cytochrome retai...

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Page, L.A.; Matthews, P.J.; Smith, P.C., 1973: Natural intestinal infection with Chlamydia psittaci in a closed bovine herd: serologic changes, incidence of shedding, antibiotic treatment of the herd, and biologic characteristics of the Chlamydiae. All cattle eventually became infected as shown by isolation of chlamydiae from faecal samples and serological tests, but clinical signs of illness were not seen. In a test group of 8 infected heifers, shedding of chlamydiae promptly ceased and ant...

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Richins, C.A., 1947: Use of the freezing-drying technique for study of vasomotor activity. Science 106(2766): 25-25

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Pe, K.M.; Tsai, C.T., 1963: Oligodendroglioma With Extracranial Metastases. Zhonghua Wai Ke Za Zhi 11: 635-637

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Boussac, A.; Un, S.; Horner, O.; Rutherford, A.W.lliam, 1998: High-spin states (S greater than or equal to 5/2) of the photosystem II manganese complex. The Mn4 complex which is involved in water oxidation in photosystem II (PSII) is known to exhibit two types of EPR signals in the S2 state, one of the five redox states of the enzyme cycle: either a multiline signal (S = 1/2) or a signal at g = 4....