CORRELATION OF IODIDE TRANSPORT WITH Na+, K+ -ATPase, HCO−3-ATPase AND CARBONIC ANHYDRASE ACTIVITIES IN DIFFERENT FUNCTIONAL STATES OF THE RAT THYROID GLAND

Chow, S. Y.; Kemp, John W.; Woodbury, Dixon M.

doi:10.1677/joe.0.0920371

Cited by 22 publications

(10 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In previous studies, we presented the effects of acetazolamide, an inhibitor of carbonic anhydrase, on iodide transport in thyroid glands of different species of animals (Chow, Kemp & Woodbury, 1982a, 1983aChow et al 19826) and on the distribution of HC03" and Cl" in turtle thyroid glands (Chow et al 1982(Chow et al , 19826, 1983c. The data suggest that anions, such as I", HC03~a nd Cl", interact with one another on the carriers for the same transport systems across the cell membranes in thyroid glands.…”

Section: Discussionmentioning

confidence: 99%

Relation between pH regulation and iodide transport in turtle thyroid glands

Chow

Woodbury²,

Yen-Chow³

1990

Journal of Endocrinology

Self Cite

View full text Add to dashboard Cite

Mechanisms of pH recovery after alkalinization and acidification by exposing or prepulsing turtle thyroid slices with a Hanks' balanced salt solution (HBSS) containing NH4Cl or CO2 were studied by examining the effects of amiloride, 4-acetamido-4'-isocyanostilbene-2,2'-disulphonic acid (SITS), frusemide and acetazolamide, and of reducing the concentration of Na+ or Cl- in the incubation medium. When alkalinization was produced either during exposure to NH4Cl or after a CO2 pulse, the pH in thyroid slices rose rapidly and then recovered gradually. Addition of SITS (0.1 mmol/l) or reduction of the Cl- concentration markedly inhibited pH recovery. However, amiloride (0.1 mmol/l) and low Na+ in the medium had no significant effect on recovery from alkalinization induced by NH4Cl exposure or by a CO2 pulse. These data suggest that pH recovery from alkalinization in turtle thyroid gland is achieved by an exchange of internal HCO3- for external Cl-. When acidification was accomplished by either exposure to CO2 or removal of NH4Cl, the pH of thyroid slices fell rapidly and then recovered gradually. If amiloride was added or the Na+ concentration in the medium was reduced, the pH recovery was greatly attenuated. However, SITS and low Cl- in the medium did not affect the recovery from an acid load in turtle thyroid slices. These results suggest that pH recovery from acidification in turtle thyroid gland is achieved by an exchange of internal H+ for external Na+. Both frusemide and acetazolamide prevented the pH recovery in turtle thyroid slices during exposure to and withdrawal from NH4Cl. These results suggest that besides the Na(+)-H+ and Cl(-)-HCO3- exchange processes, other mechanisms may also be involved in pH regulation in turtle thyroid glands. Simultaneous uptakes into turtle thyroid slices of 125I- and 22Na+ and of 125I- and 36Cl- were studied during and following exposure to NH4Cl in the absence and presence of different transport inhibitors, such as frusemide, amiloride, SITS and acetazolamide. When the thyroid slices were exposed to HBSS containing 30 mmol/l NH4Cl (alkalinization phase), the tissue/medium (T/M) ratios of 125I- increased gradually, reached the highest point in 10 min, and were maintained at this level for the next 20 min. The T/M ratios of 22Na+ and 36Cl- of thyroid slices also slowly increased after exposure to NH4Cl.(ABSTRACT TRUNCATED AT 400 WORDS)

show abstract

Section: Discussionmentioning

confidence: 99%

Relation between pH regulation and iodide transport in turtle thyroid glands

Chow

Woodbury²,

Yen-Chow³

1990

Journal of Endocrinology

Self Cite

View full text Add to dashboard Cite

show abstract

“…The homogenate was then diluted to 1 mglml for measurement of Na+,K+-, HC0,-and Mg*+-ATPase activities. ATPase activities were determined by a modification of the procedures of Bonting (1970), Kimelberg and Bourke (1973), Itaya and Ui (1966), and Stewart (1974) as described previously by Chow et al (1981). Protein content was measured by the procedure of Lowry et al (1951).…”

Section: Methodsmentioning

confidence: 99%

Subcellular Distribution of Carbonic Anhydrase and Na⁺,K⁺‐ and HCO_3‐‐ATPases in Brains of DBA and C57 Mice

1984

View full text Add to dashboard Cite

DBA/2J mice are susceptible to audiogenic seizures (ASs) in an age-dependent manner, susceptibility being maximal at 21 days of age and declining thereafter. DBA, as compared with AS-resistant C57BL/6J (C57) mice, had higher carbonic anhydrase (CA) activity in cerebral cortex, brainstem, and cerebellum homogenates at 21 days of age. CA activity was also increased in cytosolic (82%), microsomal (167%), and myelin (68%) subcellular fractions from cerebral cortex, and in cytosolic (51%) and mitochondrial (102%) fractions from brainstem of DBA mice at 21 days of age. In addition, DBA mice had a higher Na+, K+-ATPase activity in myelin from cerebral cortex, and a lower HCO3--ATPase activity in mitochondria from brainstem. The differences in CA activity in the cerebral cortex and in HCO3--ATPase were not present at 110 days of age, when DBA mice are no longer susceptible to ASs. Because CA and HCO3--ATPase are involved in maintaining a proper ionic environment for neuronal function, these data suggest that alterations in activity of these enzymes are related to the age-dependent changes in AS susceptibility in DBA mice.

show abstract

“…Rats subjected to an iodine-deficient diet also develop hypothyroidism and exhibit a compensatory rise in TSH production and release (16). Hypophysectomized rats, which display a very low level of circulating TSH, are a model of secondary (pituitary) hypothyroidism (17). Fig.…”

Section: Corroboration Of the Predicted Cytosolic-side Location Of Thmentioning

confidence: 99%

Characterization of the thyroid Na ⁺ /I ⁻ symporter with an anti-COOH terminus antibody

Levy

Dai

Riedel

et al. 1997

Proc. Natl. Acad. Sci. U.S.A.

209

142

View full text Add to dashboard Cite

The Na ؉ ͞I ؊ symporter (NIS) is the plasma membrane protein that catalyzes active I ؊ transport in the thyroid, the first step in thyroid hormone biogenesis. The cDNA encoding NIS was recently cloned in our laboratory and a secondary structure model proposed, suggesting that NIS is an intrinsic membrane protein (618 amino acids; Ϸ65.2 kDa predicted molecular mass) with 12 putative transmembrane domains. Here we report the generation of a site-directed polyclonal anti-COOH terminus NIS antibody (Ab) that immunoreacts with a Ϸ87 kDa-polypeptide present in membrane fractions from a rat thyroid cell line (FRTL-5). The modelpredicted cytosolic-side location of the COOH terminus was confirmed by indirect immunof luorescence experiments using anti-COOH terminus NIS Ab in permeabilized FRTL-5 cells. Immunoreactivity was competitively blocked by the presence of excess synthetic peptide. Treatment of membrane fractions from FRTL-5 cells, Xenopus laevis oocytes, and COS cells expressing NIS with peptidyl N-glycanase F converted the Ϸ87 kDa-polypeptide into a Ϸ50 kDa-species, the same relative molecular weight exhibited by NIS expressed in E. coli. Anti-NIS Ab immunoprecipitated both the NIS precursor molecule (Ϸ56 kDa) and the mature Ϸ87 kDa form. Furthermore, a direct correlation between circulating levels of thyroidstimulating hormone and NIS expression in vivo was demonstrated.

show abstract

CORRELATION OF IODIDE TRANSPORT WITH Na+, K+ -ATPase, HCO−3-ATPase AND CARBONIC ANHYDRASE ACTIVITIES IN DIFFERENT FUNCTIONAL STATES OF THE RAT THYROID GLAND

Cited by 22 publications

References 15 publications

Relation between pH regulation and iodide transport in turtle thyroid glands

Relation between pH regulation and iodide transport in turtle thyroid glands

Subcellular Distribution of Carbonic Anhydrase and Na⁺,K⁺‐ and HCO_3‐‐ATPases in Brains of DBA and C57 Mice

Characterization of the thyroid Na ⁺ /I ⁻ symporter with an anti-COOH terminus antibody

Contact Info

Product

Resources

About

CORRELATION OF IODIDE TRANSPORT WITH Na+, K+ -ATPase, HCO−3-ATPase AND CARBONIC ANHYDRASE ACTIVITIES IN DIFFERENT FUNCTIONAL STATES OF THE RAT THYROID GLAND

Cited by 22 publications

References 15 publications

Relation between pH regulation and iodide transport in turtle thyroid glands

Relation between pH regulation and iodide transport in turtle thyroid glands

Subcellular Distribution of Carbonic Anhydrase and Na+,K+‐ and HCO3‐‐ATPases in Brains of DBA and C57 Mice

Characterization of the thyroid Na + /I − symporter with an anti-COOH terminus antibody

Contact Info

Product

Resources

About

Subcellular Distribution of Carbonic Anhydrase and Na⁺,K⁺‐ and HCO_3‐‐ATPases in Brains of DBA and C57 Mice

Characterization of the thyroid Na ⁺ /I ⁻ symporter with an anti-COOH terminus antibody