PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “IOPANOIC ACID”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 325 records · Page 18Linked to original sources
PubMed1976

Use of tissue culture to examine neurotoxicity of contrast media.

The effect of small concentrations of diatrizoate, ioglycamate, and iopanoate salts on cultured sympathetic ganglia was studied. Biliary contrast media in clinical blood concentrations caused severe degeneration of cultured neurons, but similar concentrations of diatrizoate caused no effect. This technique may be used to measure the direct neurotoxicity or general cytotoxicity of contrast media.

Animals↗
PubMed2003

Inhibition of drug binding to human serum albumin by cholecystographic agents.

The binding of two cholecystographic agents to human serum albumin (HSA) was evaluated by means of two different complementary methodologies. In particular, the inhibition of drug HSA binding caused by iopanoic- and iophenoxic-acid was investigated by circular dichroism (CD) and resonant mirror (RM) optical biosensor techniques. The CD study allowed to obtain information both on the cholecystographic agent binding site and on the effect of the binding on the protein conformation. Iopanoic acid (IOP), a drug potentially useful for thyrotoxic disorders, resulted a direct competitor for ligands that selectively bind to site II, in agreement to literature data. No definite evidence was obtained for the highest affinity binding site of iophenoxic acid (IOPH), however, this diagnostic tool markedly affected the binding of ligands to the most characterized high affinity sites on HSA, namely sites I, II and III. Binding parameters were obtained by optical biosensor analysis: K(D) values were 3.6 x 10(-7) and 2.8 x 10(-8) M for IOP and IOPH, respectively.

Binding Sites↗
PubMed1989

Rat liver type I iodothyronine deiodinase is not identical to protein disulfide isomerase.

This study was done to test the recent hypothesis (Boado et al. (1988) Biochem. Biophys. Res. Commun. 155, 1297-1304) that type I iodothyronine deiodinase (ID-I) is identical to protein disulfide isomerase (PDI). Autoradiograms of rat liver microsomal proteins, labeled with N-bromoacetyl-[125I]triiodothyronine (BrAc[125I]T3) and separated by SDS-PAGE, show predominantly 2 radioactive bands of Mr 27 and 56 kDa. Substrates and inhibitors of ID-I inhibited labeling of the 27 kDa band but not that of the 56 kDa band. Treatment of microsomes with trypsin abolished labeling of the 27 kDa protein and destroyed the activity of ID-I but did not prevent labeling of the 56 kDa protein. Following treatment of microsomes at pH 8.0-9.5 or with 0.05% deoxycholate (DOC) PDI content and labeling of the 56 kDa protein were strongly diminished but ID-I activity and labeling of the 27 kDa protein were not affected. The latter decreased in parallel after treatment at pH greater than or equal to 10. Rat pancreas microsomes contain high amounts of PDI but show no ID-I activity. Reaction of these microsomes with BrAc[125I]T3 results in extensive labeling of a 56 kDa protein but no labeling of a 27 kDa protein. Pure PDI (Mr 56 kDa) was readily labeled by BrAc[125I]T3 but showed no deiodinase activity. These results strongly suggest that the 27 kDa band represents (a subunit of) ID-I while the 56 kDa band represents PDI. From these and other data it is concluded that PDI and ID-I are not identical proteins.

Affinity Labels↗
PubMed2002

Recombinant lysine:N(6)-hydroxylase: effect of cysteine-->alanine replacements on structural integrity and catalytic competence.

Recombinant lysine:N(6)-hydroxylase, rIucD, catalyzes the hydroxylation of L-lysine to its N(6)-hydroxy derivative, with NADPH and FAD serving as cofactors in the reaction. The five cysteine residues present in rIucD can be replaced, individually or in combination, with alanine without effecting a major change in the thermal stability, the affinity for L-lysine and FAD, as well as the k(cat) for mono-oxygenase activity of the protein. However, when the susceptibility to modification by either 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) or 2,6-dichlorophenol indophenol (DPIP) serves as the criterion for monitoring conformational change(s) in rIucD and its muteins, Cys146-->Ala and Cys166-->Ala substitutions are found to induce an enhancement in the reactivity of one of the protein's remaining cysteine residues with concomitant diminution of mono-oxygenase function. In addition, the systematic study of cysteine-->alanine replacement has led to the identification of rIucD's Cys166 as the exposed residue which is detectable during the reaction of the protein with DTNB but not with iodoacetate. Substitution of Cys51 of rIucD with alanine results in an increase in mono-oxygenase activity (approx. 2-fold). Such replacement, unlike those of other cysteine residues, also enables the covalent DPIP conjugate of the protein to accommodate FAD in its catalytic function. A possible role of rIucD's Cys51 in the modulation of its mono-oxygenase function is discussed.

Alanine↗