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1.
Biomolecules ; 13(5)2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37238619

RESUMO

BACKGROUND: Pregnancy significantly increases the demand for iron (Fe) in the female body to facilitate maternal blood volume expansion, placental development, and fetal growth. As Fe flux in pregnancy is significantly influenced by the placenta, the aim of this study was to determine the dependencies between the Fe concentration in the placenta, the infant's morphometric parameters and the woman's morphological blood parameters in the last trimester. METHODS: The study was conducted on 33 women with multiple (dichorionic-diamniotic) pregnancies from whom the placentas were drawn, and their 66 infants, including pairs of monozygotic (n = 23) and mixed-sex twins (n = 10). Fe concentrations were determined based on inductively coupled plasma atomic emission spectroscopy (ICP-OES) using ICAP 7400 Duo, Thermo Scientific. RESULTS: The results of the analysis showed that lower placental Fe concentrations were associated with deteriorated morphometric parameters of infants, including weight and head circumference. Although we found no statistically significant dependencies between Fe concentration in the placenta and the women's morphological blood parameters, higher Fe concentration in the placenta of mothers supplemented with Fe correlated with better morphometric parameters in infants compared to those whose mothers received no Fe supplementation. CONCLUSIONS: The research adds additional knowledge for placental iron-related processes during multiple pregnancies. However, many limitations of the study do not allow detailed conclusions to be assessed, and statistical data should be assessed conservatively.


Assuntos
Placenta , Gravidez de Gêmeos , Gravidez , Feminino , Humanos , Placenta/irrigação sanguínea , Peso ao Nascer , Placentação
2.
Biomolecules ; 11(4)2021 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-33800689

RESUMO

Bones are metabolically active organs. Their reconstruction is crucial for the proper functioning of the skeletal system during bone growth and remodeling, fracture healing, and maintaining calcium-phosphorus homeostasis. The bone metabolism and tissue properties are influenced by trace elements that may act either indirectly through the regulation of macromineral metabolism, or directly by affecting osteoblast and osteoclast proliferation or activity, or through becoming part of the bone mineral matrix. This study analyzes the skeletal impact of macroelements (calcium, magnesium, phosphorus), microelements (fluorine), and heavy metals (lead), and discusses the concentration of each of these elements in the various bone tissues.


Assuntos
Osso e Ossos/metabolismo , Cálcio/metabolismo , Chumbo/metabolismo , Magnésio/metabolismo , Animais , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/química , Cálcio/análise , Cálcio/farmacologia , Flúor/análise , Flúor/metabolismo , Flúor/farmacologia , Humanos , Chumbo/análise , Chumbo/toxicidade , Magnésio/análise , Magnésio/farmacologia , Fósforo/análise , Fósforo/metabolismo , Fósforo/farmacologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-32012969

RESUMO

The aim of this study was to determine the concentrations of iron, nickel, molybdenum, and vanadium in the knee joint. We also examined the relationships between the concentrations of these metals in the knee joint and the influence of varied factors on the concentration of Fe, Ni, Mo, and V. The study of these trace elements is important, because these elements are used alone and in combination in diet supplements, and they are components of biomaterials implanted in medicine. The study materials, consisting of the spongy bone, cartilage, meniscus, anterior cruciate ligament (ACL), and infrapatellar fat pad, were obtained from 34 women and 12 men from northwestern Poland. The concentrations of Ni, Fe, Mo, and V were determined using spectrophotometric atomic absorption in inductively coupled argon plasma (ICP-AES). We found significantly higher Mo concentrations in the ACL of women than men. There was a significant difference in the Mo concentration in the spongy bone between patients from cities with fewer than 100,000 inhabitants and patients from cities with more than 100,000 residents. Iron concentrations in the spongy bone were higher in non-smoking patients and those who did not consume alcohol. Vanadium concentrations were higher in the infrapatellar fat pads in abstainers. In patients who had not undergone arthroscopy surgery, V concentration was lower in cartilage. The concentrations of V in the cartilage and infrapatellar fat pad were higher in osteoporotic patients than in non-osteoporotic patients. There were significant differences in Fe concentrations in the meniscus, with the lowest in osteoporotic patients. We noted lower Mo concentrations in the spongy bone of patients with rheumatoid arthritis. Furthermore, we noted some new interactions among metals in the studied structures of the knee joint. The results reported in this study show the influence of gender, place of residence, smoking, consumption of alcohol, arthroscopy surgery, osteoporosis, and rheumatoid arthritis on the Fe, Ni, Mo, and V concentrations in the studied structures of the knee joint.


Assuntos
Ligamento Cruzado Anterior/química , Osso e Ossos/química , Articulação do Joelho/química , Metais Pesados/análise , Oligoelementos/análise , Tecido Adiposo/química , Idoso , Idoso de 80 Anos ou mais , Artroscopia , Feminino , Humanos , Ferro , Masculino , Pessoa de Meia-Idade , Molibdênio , Níquel , Polônia , Espectrofotometria Atômica , Vanádio
4.
Ecotoxicology ; 29(1): 1-12, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31734834

RESUMO

This study examined the concentration of total mercury (THg) and selenium (Se), as well as the molar ratio of Se:THg in hair samples of terrestrial animals. THg and Se concentrations were measured from the hair of raccoons (Procyon lotor) and European wildcats (Felis s. silvestris) from Germany and Luxembourg. Median THg concentrations in hair from raccoons and wildcats were 0.369 and 0.273 mg kg-1 dry weight (dw), respectively. Se concentrations were higher in the hair of raccoons than of wildcats (0.851 and 0.641 mg kg-1 dw, respectively). Total mercury concentration in hair of raccoons from Luxembourg was almost 5× higher that found in hair of raccoons from Germany; however, Se concentration was similar. Thus, molar ratio of Se:THg was ~4× higher in the hair of raccoons from Germany than those from Luxembourg. Significant negative correlation was found between THg concentration and Se:THg molar ratio in both wildcats and raccoons.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Felis , Cabelo/química , Mercúrio/análise , Guaxinins , Selênio/análise , Animais , Alemanha , Luxemburgo
5.
Exp Parasitol ; 199: 24-29, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30796912

RESUMO

The genus Acanthamoeba, which may cause different infections in humans, occurs widely in the environment. Lung inflammation caused by these parasites induces pulmonary pathological changes such as pulmonary necrosis, peribronchial plasma cell infiltration, moderate desquamation of alveolar cells and partial destruction of bronchial epithelial cells, and presence of numerous trophozoites and cysts among inflammatory cells. The aim of this study was to assess the influence of plant extracts from Artemisia annua L. on expression of the toll-like receptors TLR2 and TLR4 in lungs of mice with acanthamoebiasis. A. annua, which belongs to the family Asteraceae, is an annual plant that grows wild in Asia. In this study, statistically significant changes of expression of TLR2 and TLR4 were demonstrated. In the lungs of infected mice after application of extract from A. annua the expression of TLRs was observed mainly in bronchial epithelial cells, pneumocytes (to a lesser extent during the outbreak of infection), and in the course of high general TLR expression. TLR4 in particular was also visible in stromal cells of lung parenchyma. In conclusion, we confirmed that a plant extract of A. annua has a modulatory effect on components of the immune system such as TLR2 and TLR4.


Assuntos
Acanthamoeba/fisiologia , Amebíase/tratamento farmacológico , Artemisia annua/química , Pneumopatias Parasitárias/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Receptores Toll-Like/metabolismo , Amebíase/metabolismo , Animais , DNA Complementar/metabolismo , Imuno-Histoquímica , Pulmão/parasitologia , Pulmão/patologia , Pneumopatias Parasitárias/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia , RNA Mensageiro/metabolismo , RNA de Protozoário/genética , RNA de Protozoário/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Reversa , Receptor 2 Toll-Like/efeitos dos fármacos , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptores Toll-Like/efeitos dos fármacos , Receptores Toll-Like/genética
6.
Environ Geochem Health ; 40(4): 1683-1695, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29492803

RESUMO

The aim of the study was to evaluate Hg and Se concentrations and Se:Hg molar ratios in the placenta, umbilical cord and fetal membranes, and to examine the relationship between the concentrations of the elements and selected factors. The study material consisted of the placenta, umbilical cord and fetal membranes obtained from 91 healthy women from northwestern and central Poland. In our study mean Hg and Se concentrations in afterbirth were ~ 0.01 mg/kg dry weight (dw) and ≤ 0.5 mg/kg dw, respectively. Correlation analysis showed negative relationships between placenta weight and Se concentration in the placenta and umbilical cord, as well as between placenta length and Se levels in the umbilical cord. We found negative correlations between THg concentration in the placenta and birth weight and between Se concentration in the placenta and umbilical cord and the morphological parameters of the placenta. Furthermore, we noted new types of interactions in specific parts of the afterbirth. In our study, Se:THg molar ratios ranged from 5 to 626; these values indicate protection against Hg toxicity.


Assuntos
Membranas Extraembrionárias/metabolismo , Mercúrio/metabolismo , Placenta/metabolismo , Selênio/metabolismo , Cordão Umbilical/metabolismo , Adulto , Feminino , Humanos , Gravidez
7.
Exp Parasitol ; 185: 17-22, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29317241

RESUMO

The treatment of acanthamoebiasis is a still a problem. Our previous studies showed that the application of extracts from Artemisia annua L. significantly prolonged the survival of mice infected by Acanthamoeba. This plant has medicinal properties in the treatment of human parasitic diseases. The aim of this study was to evaluate the effects of A. annua on expression of Toll-like receptors (TLRs) 2 and 4 in brain of mice with Acanthamoeba infection. Mice were infected with Acanthamoeba sp. strain Ac309 (KY203908) by intranasal inoculation without and after application of A. annua extract. The administration of extract from A. annua significantly reduced the level of expression of TLR2 and modified the level of expression of TLR4. A. annua extract is a natural substance that is well tolerated in animals and may be considered as a combination therapy in treatment of acanthamoebiasis. Our study suggested that A. annua extract may be used as an alternative therapeutic tool.


Assuntos
Acanthamoeba/efeitos dos fármacos , Amebíase/tratamento farmacológico , Artemisia annua/química , Encéfalo/metabolismo , Fitoterapia , Receptores Toll-Like/efeitos dos fármacos , Amebíase/metabolismo , Animais , Encéfalo/patologia , Expressão Gênica , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor 2 Toll-Like/efeitos dos fármacos , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/efeitos dos fármacos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
8.
J Trace Elem Med Biol ; 44: 201-208, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28965577

RESUMO

Due the long-term nature of joint tissue remodeling processes, knee structures including meniscus and anterior cruciate ligament (ACL) can be a model for studying the bioaccumulation of mercury (Hg) and selenium (Se). The accumulation and retention of Hg in human tissues can have a negative effect on the proper functioning of homeostasis-affecting organisms. A factor of chronic poisoning with Hg forms is probably the Se:Hg ratio in tissues. Se:Hg molar ratios below one may increase Hg toxicity potentials, while molar ratios that approach or exceed one effectively may protect against Hg toxicity. Therefore, the aim of the study was to determine total mercury (THg), Se, and Se:THg molar ratios in the cartilage, meniscus and ACL of patients with osteoarthritis (OA) from northwestern Poland. In all studied samples (n=95), we observed higher Se than THg concentration. Taking into consideration the biological factors, we found significantly higher THg levels in the cartilage of women, patients under 65 years of age, patients without hypertension and in the ACL of patients with spinal degenerative disease. We found higher Se levels in the meniscus in women than in men. In all studied parts of the knee joint, we found the Se:THg molar ratio higher than one, which suggests that the joint forming structures are not much exposed to THg. Moreover the results reported here may provide a basis for establishing reference values for the meniscus and ACL in patients with OA who had undergone knee replacement surgery.


Assuntos
Ligamento Cruzado Anterior/metabolismo , Cartilagem/metabolismo , Menisco/metabolismo , Mercúrio/metabolismo , Selênio/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Saúde , Humanos , Masculino , Pessoa de Meia-Idade
9.
Ecotoxicol Environ Saf ; 136: 24-30, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27810577

RESUMO

The aim of this study was to investigate and compare total mercury (Hg), selenium (Se), and Se:Hg molar ratios in fish muscles (phytophages n=3; benthophages n=32; predators n=5) and semiaquatic carnivores, including piscivores (the European otter n=8, the feral American mink n=7) and the omnivorous raccoon (n=37) from a riverine European ecosystem in a Se-deficient area. The Hg concentration in fish reached 0.337µg/g dry weight, dw (0.084µg/g wet weight, ww). We found significant differences among Hg levels in tested vertebrate groups (predators vs benthophages: 0.893 vs 0.281µg/g; piscivores vs omnivores: 6.085 vs 0.566µg/g dw). Fish groups did not differ in Se concentrations, with a mean value of 0.653µg/g dw. Significant differences were revealed between Se levels in piscivorous and omnivorous carnivores (0.360 vs 0.786µg/g dw, respectively). Fish Se:Hg molar ratio values were >2.2. Benthophages had higher the ratio than predators but similar to phytophages. Among carnivores, piscivores had much lower the ratio than raccoon (0.14 vs 3.75) but raccoon and fish medians did not significantly differ. We found almost two times higher Se levels in fish and raccoons compared to piscivores, possibly resulting from lower fish Se digestibility by piscivores in contrast to higher absorption of plant Se by many fish and omnivorous raccoons. Considering that a tissue Se:Hg molar ratio <1 may be connected with a Hg toxicity potential increase, we assume that piscivores in Se-deficient area are in worse situation and more exposed to Hg than fish and omnivores.


Assuntos
Carnívoros/metabolismo , Peixes/metabolismo , Mercúrio/metabolismo , Músculos/química , Selênio/metabolismo , Animais , Compostos de Selênio/metabolismo , Poluentes Químicos da Água/análise
10.
Ecotoxicol Environ Saf ; 101: 107-15, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24507135

RESUMO

Although the relationship between mercury (Hg) and selenium (Se) has been studied in wild birds in areas with sufficient or excessive Se levels, little is known about this relationship in areas where the supply of Se is limited. As Hg detoxification is based on the production of biologically inactive Hg-Se complexes, the aim of this study was to investigate the relationships between the concentrations of total mercury (THg), methylmercury (MeHg), inorganic mercury (InHg=THg-MeHg), percent MeHg of THg, Se and molar ratios (THg:Se, MeHg:Se, InHg:Se) in the breast muscle (n=16) of the piscivorous common mergansers (Mergus merganser) from a Se-deficient and moderately Hg-polluted area in Poland. Mergansers were divided into two groups differing in condition (A-very good condition; C-moderate condition). Concentrations of THg, MeHg and Se were determined by atomic absorption spectrometry, modified gas chromatography atomic fluorescence spectroscopy, and spectrofluorometric methods, respectively. In all studied mergansers, mean concentrations of THg, MeHg, InHg, and Se in muscle were 2.63, 1.92, 0.46, and 0.54µgg(-1)dw, respectively. THg and MeHg concentrations in the muscle of group A mergansers were greater than in group C. The ratio of THg:Se was higher in group A than in group C (2.32 vs 1.36; p<0.01), as well as the molar ratio of MeHg:Se (A vs C: 1.98 vs 1.03; p<0.05). Comparisons between mergansers from Poland and Canada showed similar THg and percent MeHg in the muscle, but mergansers from Poland had several times lower Se levels and higher THg:Se ratios (>2.0) than the Canadian mergansers and other European and North American waterbirds. We found statistically significant positive correlations (MeHg-THg, percent MeHg/THg-MeHg, percent InHg/THg-InHg, THg:Se-THg, MeHg:Se-THg, THg:Se-MeHg, MeHg:Se-MeHg, InHg:Se-InHg, MeHg:Se-THg:Se) and some negative correlations (percent InHg/THg-MeHg, percent MeHg/THg-InHg, THg:Se-Se, MeHg:Se-Se). As THg and percent MeHg in the studied mergansers were similar to populations living in non-Se-deficient areas, it is likely that different mechanisms of muscle Hg detoxification have evolved in mergansers populations living in Se-deficient areas.


Assuntos
Patos/fisiologia , Mercúrio/análise , Músculos/química , Selênio/análise , Poluentes Químicos da Água/análise , Fatores Etários , Animais , Compostos de Metilmercúrio/análise , Polônia
11.
Environ Toxicol Chem ; 33(2): 421-30, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24174120

RESUMO

The subject of the present study was the piscivorous common mergansers (Mergus merganser). The total mercury (THg), methylmercury (MeHg), selenium (Se) inorganic mercury (InHg; THg - MeHg), percentage of THg that is MeHg (%MeHg), molar ratios (THg:Se, MeHg:Se, InHg:Se), and their mutual relations in livers and kidneys were determined in ducks from an Se-deficient area in Poland. The authors verified a hypothesis that, as a result of living in an Se-deficient region, mergansers from Poland should have higher THg:Se ratios than other waterbirds with similar THg tissue levels. Although a comparison of healthy mergansers from Poland and Canada showed similar THg tissue contents, the group in the present study had a few times lower Se levels and higher THg:Se ratios (overall means >1.7 in both livers and kidneys in all studied individuals) than the Canadian group and other European and North American waterbirds. The authors found significant correlations between various relations, including MeHg-THg, InHg-THg, Se-THg, %MeHg-THg, InHg/%THg-THg, %MeHg/THg-InHg, %InHg/THg-InHg, MeHg:Se-THg:Se, InHg:Se-THg:Se, InHg:Se-MeHg:Se in liver and InHg-THg, Se-THg, Se-InHg, %MeHg-THg, %MeHg-InHg, %InHg/THg-InHg, THg:Se-THg, InHg:Se-THg, MeHg:Se-MeHg, THg:Se-InHg, InHg:Se-InHg, and InHg:Se-THg:Se in kidney. It is likely that the main factor responsible for the high value of THG:Se ratio (>1) in mergansers from Poland is Se deficiency in central and northern Europe. Therefore, this element is unlikely to participate in the detoxification of Hg in these birds.


Assuntos
Patos , Mercúrio/análise , Compostos de Metilmercúrio/análise , Selênio/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental , Feminino , Rim/química , Fígado/química , Masculino , Polônia
12.
Biol Trace Elem Res ; 152(2): 195-203, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23377610

RESUMO

The aim of this study was to compare zinc, copper, lead, cadmium, and mercury concentrations in the bones of long-living mammals-humans (Homo sapiens) and Canidae (dogs Canis familiaris and foxes Vulpes vulpes) from northwestern Poland and to determine the usefulness of Canidae as bioindicators of environmental exposure to metals in humans. Zinc concentrations in cartilage with adjacent compact bone and in spongy bone were highest in foxes (∼120 mg/kg dry weight (dw)) and lowest in dogs (80 mg/kg dw). Copper concentrations in cartilage with adjacent compact bone were greatest in foxes (1.17 mg/kg dw) and smallest in humans (∼0.8 mg/kg dw), while in spongy bone they were greatest in dogs (0.76 mg/kg dw) and lowest in foxes (0.45 mg/kg dw). Lead concentrations in both analyzed materials were highest in dogs (>3 mg/kg dw) and lowest in humans (>0.6 mg/kg dw). Cadmium concentration, also in both the analyzed materials, were highest in foxes (>0.15 mg/kg dw) and lowest in humans (>0.04 mg/kg dw). Mercury concentration in bones was low and did not exceed 0.004 mg/kg dw in all the examined species. The concentrations of essential metals in the bones of the examined long-living mammals were similar. The different concentrations of toxic metals were due to environmental factors. As bone tissues are used in the assessment of the long-term effects of environmental exposure to heavy metals on the human body, ecotoxicological studies on the bones of domesticated and wild long-living mammals, including Canidae, may constitute a significant supplement to this research.


Assuntos
Osso e Ossos/metabolismo , Oligoelementos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Cádmio/metabolismo , Cobre/metabolismo , Cães , Feminino , Raposas , Humanos , Chumbo/metabolismo , Masculino , Mercúrio/metabolismo , Pessoa de Meia-Idade , Zinco/metabolismo
13.
Med Sci Monit ; 17(1): BR16-26, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21169903

RESUMO

BACKGROUND: The aim of this study was to assess the effect of diet supplementation with L-ascorbic acid (500 mg/L), tocopherol (3 mg/kg b.w.), and/or a water soluble analog of tocopherol (Trolox) (48 mg/L) on ion transport in the colon of rats subjected to a chronic exposure (9 months) to 0.1% lead acetate in drinking water. MATERIAL/METHODS: The electrophysiological parameters of the colon wall were measured with Ussing methods. Lead content in the whole blood was analyzed by graphite furnace atomic absorption spectrometry (GFAAS) using Zeeman correction. L-ascorbic acid and tocopherol in plasma was measured by high performance liquid chromatography. Immunohistochemical reaction was carried out for visualization of occludin, the intracellular tight junction protein. RESULTS: We showed a strong inhibitory effect of lead on the electrophysiological parameters, changes in intestinal permeability, disappearance of junctional occludin, decreased amount of mucus covering the colon surface, and the accumulation of PAS-positive substance in the apical region of the cytoplasm in the absorptive cells. CONCLUSIONS: Supplementation with tocopherol or Trolox did not exert a beneficial influence on the studied parameters. L-ascorbic acid positively influenced the examined electrophysiological parameters, as it cancelled the inhibitory influence of lead on ion transport in the rat colon. L-ascorbic acid also protected against tight junction disruption of epithelial cells in the colon of the lead-treated rats. A similar effect was observed in the group of rats receiving lead and supplemented with L-ascorbic acid plus Trolox.


Assuntos
Ácido Ascórbico/farmacologia , Colo/efeitos dos fármacos , Colo/fisiologia , Compostos Organometálicos/toxicidade , Tocoferóis/farmacologia , Poluentes Químicos da Água/toxicidade , Animais , Ácido Ascórbico/sangue , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Eletrofisiologia , Imuno-Histoquímica , Transporte de Íons/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Ocludina , Compostos Organometálicos/sangue , Ratos , Espectrofotometria Atômica , Tocoferóis/sangue
14.
Pol J Pharmacol ; 55(2): 221-6, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12926550

RESUMO

The aim of this study was to determine the effect of starvation on the transport of sodium and chloride ions in the epithelium of rabbit caecum. The experiment consisted in measuring transepithelial electrical potential (PD in mV) and the transepithelial electrical potential difference (dPD in mV) of an isolated fragment of rabbit caecum, before and after 4-day-long starvation. The studied tissue was incubated in Ringer solution and subsequently ion transport was modified through incubation in the Ringer solution supplemented with amiloride or/and bumetanide. It was demonstrated that the values of electrophysiological parameters of the tissue fragments of caecum from starved rabbits were substantially lower than the values for the fragments of control caecum. A similar relationship was observed also in the reaction of this tissue to mechanical stimuli. After the incubation of the caecum tissue fragments in the presence of amiloride or/and bumetanide, the value of transepithelial electrical potential and the sensitivity to mechanical stimuli decreased in both groups studied. Experimental data presented in this paper indicate that the starvation process has effect on lowering sodium and chloride ion transport and decreasing sensitivity of the epithelium of the caecum to mechanical stimuli.


Assuntos
Amilorida/farmacologia , Bumetanida/farmacologia , Ceco/efeitos dos fármacos , Privação de Alimentos , Transporte de Íons/efeitos dos fármacos , Animais , Ceco/metabolismo , Ceco/fisiologia , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/metabolismo , Canais de Cloreto/fisiologia , Eletrofisiologia , Técnicas In Vitro , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiologia , Transporte de Íons/fisiologia , Coelhos , Bloqueadores dos Canais de Sódio/farmacologia , Canais de Sódio/metabolismo , Canais de Sódio/fisiologia
15.
Pol J Pharmacol ; 54(5): 475-82, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12593534

RESUMO

Effect of capsaicin, a stimulator of C-fibres, on ion transport in the caecum of rabbits was studied using electrophysiological methods, designed to evaluate ionic currents occurring in epithelial tissues. The experiments consisted in measuring transepithelial electrical potential difference (dPD) of an isolated fragment of rabbit's caecum, placed in a Ussing apparatus. The ion transport was modified through incubation in Ringer solution, supplemented with amiloride, bumetanide, and capsaicin. Capsaicin was also administered with peristalting pump. The experiments demonstrated that the inhibition of sodium ions transport caused by incubation with amiloride and incubation with capsaicin slowed down mechanical reaction to electrical potential difference. On the other hand, immediately after the administration, the capsaicin effect on C-fibres modified electrophysiological reaction of the caecum to mechanical stimulation. Physiological and pharmacological experiments reveal that a component dependent on activation of C-fibres contributes to the reaction of ion transport activation following mechanical stimulation.


Assuntos
Capsaicina/farmacologia , Ceco/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Amilorida/farmacologia , Animais , Bumetanida/farmacologia , Ceco/fisiologia , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/fisiologia , Eletrofisiologia , Feminino , Técnicas In Vitro , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/inervação , Mucosa Intestinal/fisiologia , Transporte de Íons/fisiologia , Masculino , Fibras Nervosas Amielínicas/efeitos dos fármacos , Fibras Nervosas Amielínicas/fisiologia , Estimulação Física , Coelhos , Bloqueadores dos Canais de Sódio/farmacologia , Fatores de Tempo
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