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S Hudecová

Publications and source records attributed to S Hudecová.

15 recordsLinked to original sources
PubMed1997

Nuclear all-trans retinoic acid receptors in liver of rats with diet-induced insulin resistance.

Retinoic acid receptor alpha (RAR alpha) expression and RAR binding characteristics were investigated in the liver of rats with high-sucrose (HS) diet-induced insulin resistance. Animals were fed a basal (B) or HS (63 cal%) diet with or without fish oil (FO) (30% w/w of total fatty acids) for two weeks. A significant augmentation (p < 0.01) in the RAR alpha mRNA accumulation in rats fed HS diet when compared to rats fed B diet was demonstrated. In comparison with rats fed B + FO diet, a significant increase (p < 0.005) in the RAR alpha expression was found in rats fed HS + FO diet. In [3H]-retinoic acid (RA) binding studies, Scatchard plots confirmed a significant increase (p < 0.05) in the RAR maximal binding capacity (Bmax) only in rats fed HS + FO diet when compared to rats fed B diet. No significant changes in the association constant (Ka) were found among the groups when compared to rats fed B diet. In contrast to RAR alpha, a significant decrease (p < 0.005) in nuclear thyroid hormone receptor alpha 1 (TR alpha 1) expression was found in rats fed HS diet when compared to rats fed B diet. A significant decrease (p < 0.05) in the TR alpha 1 expression was also detected in rats fed HS + FO diet in comparison with rats fed B + FO diet. In addition, an analogous pattern in the expression of the TR isoform (TR alpha 2) was evaluated as well. In conclusion, the high-sucrose diet-induced insulin resistance might be associated with an increased RAR alpha expression and RAR population, and also with a decreased TR alpha 1 and TR alpha 2 mRNA accumulation.

Animals↗
PubMed1995

PKU in Slovakia: mutation screening and haplotype analysis.

The restriction fragment length polymorphism haplotypes and seven common mutations in the phenylalanine hydroxylase gene were analysed in 49 unrelated Slovak phenylketonuria (PKU) families of Caucasian origin. The predominant mutation in this population sample is R408W, with a frequency of 45.9%. In addition, four other mutations have been identified at relatively high frequencies: IVS12nt1, 10.2%; R158Q, 7.1%; R261Q, 7.1%; R252W, 2.0%. The mutation-haplotype associations correspond to those described in other European populations. The high proportion of mutations (72.4%) amenable to simple rapid detection based on the polymerase chain reaction provides a good basis for direct DNA-diagnosis of PKU in the Slovak population.

Haplotypes↗
PubMed1995

In vitro effects of sodium selenite on nuclear 3,5,3'-triiodothyronine (T3) receptor gene expression in rat pituitary GH4C1 cells.

The present study was undertaken in order to investigate the effects of sodium selenite on: 1. The growth of rat pituitary GH4C1 cells; 2. The nuclear T3 receptor gene expression; 3. The cytoplasmic protein phosphorylation; and 4. The prolactin secretion in rat pituitary GH4C1 cell line. Sodium selenite (up to 2.5 microM) has no inhibitory effect on GH4C1 cell proliferation as well as the prolactin secretion. On the other hand, 0.5 microM sodium selenite significantly decreases the rate of mRNA synthesis and/or degradation of both, the alpha 1 form of the T3 receptor (TR alpha 1) and the alpha 2 isoform of the T3 receptor. At 1 microM of sodium selenite, significant changes in the electrophoretic profile of low molecular mass cytoplasmic proteins were found, moreover, sodium selenite (1 microM) also considerably affects phosphorylation of a higher molecular mass proteins. The results based on the in vitro experiments suggest that sodium selenite may affect specific processes at the pretranslational level as well as it may also take part in processes of posttranslational modification of protein(s), the cell vitality and the cell growth remaining unchanged.

Animals↗
PubMed1995

[DNA analysis in the determination of a predisposition for hypertension].

Angiotensinogen gene belongs to the genes designated as hypertension candidate genes. These genes might participate in development of hypertension. The aim of this work was to establish frequency of the mutant allele M235T on angiotensinogen gene in Slovak population and compare this frequency with that obtained from the group of hypertensive patients. We tested DNA from 120 healthy individuals and 20 hypertensive patients. By polymerase chain reaction followed by restriction analysis we determined frequency of mutant allele M235T in healthy population as well as in the group of hypertensive patients. We have found that frequency of the mutant allele in Slovak population was 0.33, while among hypertensive patients 0.45. Percentage of heterozygosity for M235T allele was 44.5%. Frequency of this mutant allele was significantly higher among women compared to men (0.38 vs. 0.27). Increased frequency of M235T allele among hypertensive patients compared to healthy population confirm that M235T mutation is bound to increased blood pressure. This quick and noninvasive method should help in the future to determine the possible risk of hypertension development. (Tab. 1, Fig. 2, Ref. 9.)

Adult↗
PubMed1994

[DNA analysis in classic phenylketonuria--screening for mutations and haplotype analysis in Slovak families].

Authors in this contribution present the results of screening for mutations in PAH gene responsible for classical phenylketonuria (PKU), and that of haplotype analysis, based on DNA analysis in 49 Caucasian families with at least one affected child from Slovak Republic. The clearly predominant PKU mutation in this population was the R408W with proportion of 45.9% among all PKU mutations. In addition four other mutations have been identified: IVS12nt1-10.2%, R158Q-7.1%, R261Q-7.1%, and R252W-2.0%. the overall proportion of identified PKU mutations equals 72.4%. Considering the fact, that these mutations are amenable to rapid and rather simple detection using PCR, the DNA analysis is recommended as a method of direct diagnosis in clinical practice as well as in prevention.

DNA↗
PubMed1994

Identification and isolation of omega-conotoxin binding protein from rabbit brain.

N-type of calcium channels belongs to a family of voltage-dependent calcium channels and occurs predominantly in neuronal tissue. One of the basic characteristics of this channel type is binding of omega-conotoxin GVIA--a potent blocker of the calcium current through this type of channel. We have found that two proteins with Mw 170-175 kD and 45-60 kD possess omega-conotoxin GVIA binding sites, while the only protein with Mw 170-175 kD was able to transport calcium after reconstitution into the phospholipid vesicles. The same results were obtained from human embryonic brain. Our results suggest that protein with Mw 170-175 kD corresponds to the alpha 1-subunit of N-type of voltage-dependent calcium channel.

Animals↗
PubMed1992

[Different localization of L-type and N-type activated calcium channels in the brain tissue cells in rabbits].

Postsynaptosomal, microsomal (HMF), and synaptosomal fractions were isolated from rabbit brain tissue according to two different protocols. The binding of 1,4-dihydropyridines and transport of 45Ca2+ indicated the presence of L-type of voltage operated calcium channels (VOCC) in the postsynaptosomal and microsomal membranes. The 200 kD protein, which bound 1,4-dihydropyridines and transported 45Ca2+, was identified as alpha-subunit of L-type VOCC. The authors further showed that after centrifugation of synaptosomal proteins into sucrose density gradient the fraction of proteins which sedimented in 1.10(1) mol/l sucrose was able to bind 125I-omega-conotoxin GVIA. The separation of these proteins in 6% PAGE resulted in proteins of Mw from 40 to 200 kD. The 170 kD protein extracted from PAGE bound omega-conotoxin along with 45-65 kD proteins, which are supposed to be subunits of the neuronal acetylcholine receptor. (Fig. 6, Ref. 15.).

Animals↗
PubMed1991

The dihydropyridine receptor: expression of 190 kD alpha 1 subunit in crayfish muscle.

The existence of dihydropyridine receptor in crayfish striated muscle was proved by Northern blot analysis and 3H PN 200--110 binding. The alpha 1 subunit is encoded by a 8300 nt mRNA population and is expressed as 190 kD protein in crayfish T-tubular system, which binds 3H PN 200--110 (Bmax 1.5 +/- 0.4 pmol/mg protein and KD 6.2 +/- 0.8 nmol/l). The purified protein is phosphorylated by cAMP-dependent protein kinase. The dihydropyridine receptor in crayfish striated muscle also contains alpha 2 subunit, which on Northern blot gives the same signal as the alpha 2 subunit from rabbit skeletal muscle.

Animals↗
PubMed1990

The Ca2+ antagonists binding cytosolic protein has properties of the Ca2+ channel.

In our previous work (Krizanová et al. 1989) we have described a protein from rabbit skeletal muscle cytosolic fraction, which is able to bind dihydropyridines and phenothiazines. In the present work conclusive evidence is provided for the ability of the phospholipid-reconstituted cytosolic protein to transport calcium. The calcium transport was stimulated by BAY K 8644 and inhibited in the presence of PN 200-110. Our observations were confirmed also by electrophysiological measurements on planar lipid bilayers. The possibility that the cytosolic fraction was contaminated with membranes could be definitely ruled out. Nevertheless, the nature of the protein under study is still in the frame of guess.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1989

Is Ca2+ antagonists binding protein from cytosolic fraction the precursor of alpha 1-subunit of Ca2+ channel?

The binding of Ca2+ antagonists to soluble proteins obtained by ammonium sulphate precipitation from cytosol fraction of rabbit skeletal muscles was studied. The KD values for 3H D-888 and 3H PN 200-110 binding to soluble proteins were 21.3 +/- 3.1 nmol.l-1 and 28.8 +/- 8.9 nmol.l-1 respectively. Photoaffinity labelling of the soluble proteins with the arylazide 1,4-dihydropyridine probe 3H azidopine resulted in labelling of the 85-95 K protein band as determined by SDS polyacrylamide gel electrophoresis. Partial purification of prelabelled soluble sample by gel filtration on Sephadex G-150 gave a more precise molecular weight of 90 +/- 2.5K. Polyclonal antibodies prepared against Ca2+ channel complex from rabbit muscle T-tubules inhibited the 3H PN 200-110 binding. Our results suggest that the soluble protein with Mr = 90K +/- 2.5K may be a precursor of the large subunit of the membrane bound L-type Ca2+ channel in rabbit skeletal muscle.

Affinity Labels↗