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1.
Nat Commun ; 9(1): 2238, 2018 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-29884824

RESUMO

Feshbach resonances are a powerful tool to tune the interaction in an ultracold atomic gas. The commonly used magnetic Feshbach resonances are specific for each species and are restricted with respect to their temporal and spatial modulation. Optical Feshbach resonances are an alternative which can overcome this limitation. Here, we show that ultra-long-range Rydberg molecules can be used to implement an optical Feshbach resonance. Tuning the on-site interaction of a degenerate Bose gas in a 3D optical lattice, we demonstrate a similar performance compared to recent realizations of optical Feshbach resonances using intercombination transitions. Our results open up a class of optical Feshbach resonances with a plenitude of available lines for many atomic species and the possibility to further increase the performance by carefully selecting the underlying Rydberg state.

2.
Eur J Med Genet ; 54(3): 357-60, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21187176

RESUMO

15q11.2 microdeletion has been suggested as a new microdeletion syndrome and several patients have been described in the literature. We report seven new patients belonging to six families, age 9-24 years old, with a 350 kb 15q11.2 deletion of the four highly conserved genes (TUBGCP5, NIPA1, NIPA2 and CYFIP1) earlier reported. All our patients had some degree of learning difficulties, delayed development and/or behavioural problems. Common dysmorphic features and congenital malformations were not characteristics of our patients. The deletion was inherited from a mildly affected parent in all cases tested (5/6 families available for testing both parents). These seven new cases confirm some of the features earlier reported to be associated with 15q11.2 deletion, and help to further delineate the phenotype associated with 15q11.2 deletion.


Assuntos
Anormalidades Múltiplas/genética , Deleção Cromossômica , Transtornos Cromossômicos/genética , Cromossomos Humanos Par 15/genética , Deficiências do Desenvolvimento/patologia , Anormalidades Múltiplas/patologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Adolescente , Proteínas de Transporte de Cátions , Criança , Transtornos Cromossômicos/patologia , Hibridização Genômica Comparativa , Feminino , Deleção de Genes , Humanos , Deficiências da Aprendizagem/patologia , Masculino , Proteínas de Membrana/genética , Transtornos Mentais/patologia , Proteínas Associadas aos Microtúbulos/genética , Técnicas de Amplificação de Ácido Nucleico , Adulto Jovem
3.
Mol Ecol ; 20(2): 219-34, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21143329

RESUMO

We used a population genetic approach to quantify major population subdivisions and patterns of migration within a broadly distributed Indo-Pacific parrotfish. We genotyped 15 microsatellite loci in Scarus rubroviolaceus collected from 20 localities between Africa and the Americas. A STRUCTURE model indicates the presence of four major populations: Eastern Pacific, Hawaii, Central-West Pacific and a less well-differentiated Indian Ocean. We used the isolation and migration model to estimate splitting times, population sizes and migration patterns between sister population pairs. To eliminate loci under selection, we used BayeScan to select loci for three isolation and migration models: Eastern Pacific and Central-West Pacific, Hawaii and the Central-West Pacific, and Indian Ocean and the Central-West Pacific. To test the assumption of a stepwise mutation model (SMM), we used likelihood to test the SMM against a two-phase model that allowed mutational complexity. A posteriori, minor departures from SMM were estimated to affect ≤2% of the alleles in the data. The data were informative about the contemporary and ancestral population sizes, migration rates and the splitting time in the eastern Pacific/Central-West Pacific comparison. The model revealed a splitting time ∼17,000 BP, a larger contemporary N(e) in the Central-West Pacific than in the eastern Pacific and a strong bias of east to west migration. These characteristics support the Center of Accumulation model of peripatric diversification in low-diversity peripheral sites and perhaps migration from those sites to the western Pacific diversity hotspot.


Assuntos
Migração Animal , Especiação Genética , Variação Genética , Perciformes/genética , Animais , Fluxo Gênico , Genótipo , Oceano Índico , Metagenômica , Repetições de Microssatélites , Mutação , Oceano Pacífico , Filogenia , Densidade Demográfica , Dinâmica Populacional
4.
Cancer Lett ; 172(2): 151-7, 2001 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-11566490

RESUMO

Bombesin-like peptides (BLP) and their receptors are widely distributed throughout the intestine and are potential mitogens for gastrointestinal cancers. In this study we characterized the proliferation induced by BLP in the human adenocarcinoma cell line HT-29. The number of HT-29 cells, partially serum deprived (1% fetal bovine serum) for 48 h, was increased after 24 h of stimulation with bombesin, GRP, neuromedin B (NMB) and neuromedin C (NMC) ranging from 0.1 nM up to 1 microM. Reverse transcription polymerase chain reaction studies, revealed the presence of mRNA for NMB and for the GRP preferring receptor (GRP-R). mRNA for GRP, NMB preferring receptor (NMB-R) and bombesin receptor subtype 3 (BRS-3) were not detected. [D-Phe(6)]bombesin-(6-13)methyl ester (A1) and BIM-23127 (A2), are considered as inhibitors of binding to GRP-R and NMB-R, respectively. Surprisingly, A1 and A2 stimulated the proliferation of HT-29 cells. Moreover, in the simultaneous presence of 1 microM A1 and 0.1 microM GRP or 0.1 nM or 0.1 microM bombesin, inhibition of the proliferation was observed. Our data demonstrate that the proliferation induced by BLP in HT-29 cells is due to interaction with the GRP-R.


Assuntos
Bombesina/farmacologia , Peptídeo Liberador de Gastrina/farmacologia , Neurocinina B/farmacologia , Fragmentos de Peptídeos/farmacologia , Bombesina/genética , Bombesina/metabolismo , Divisão Celular/efeitos dos fármacos , Células HT29 , Humanos , Neurocinina B/análogos & derivados , RNA Mensageiro/análise , Receptores da Bombesina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Peptides ; 22(12): 2039-44, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11786188

RESUMO

In frog skin, tachykinins stimulate ion transport by interaction with NK1-like receptors. The structural requirements of the peptide are the presence of the C-terminal sequence Phe-X-Gly-Leu-Met-NH(2) and at least one Pro residue in the N-terminal sequence. In this paper, we demonstrate that the C-terminal amino acid must be amidated but it can be different from Met, and that the sequence cannot be longer or shorter than 11-12 amino acids. Unexpectedly, Ranamargarin (14 amino acids, no Pro residue) increased the short circuit current value by 48 +/- 0.3%. On the basis of considerable experimental evidence, we suggest that Ranamargarin interacts with a receptor different from those of other tachykinins.


Assuntos
Pele/metabolismo , Taquicininas/fisiologia , Sequência de Aminoácidos , Animais , Transporte de Íons , Dados de Sequência Molecular , Rana esculenta , Taquicininas/química
6.
Cancer Lett ; 152(2): 217-22, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10773415

RESUMO

Several lines of evidence suggest that non-steroidal antiinflammatory drugs (NSAIDs) have anticarcinogenic effects. The causal relationship linking the preventive effect of NSAIDs on colon cancer and the inhibition of prostaglandin synthesis is questioned by the contrasting results obtained by many laboratories. The experiments reported in this paper demonstrate that prostaglandin E(2) (PGE(2)) did not stimulate the proliferation in HT-29 human colon adenocarcinoma cells under several experimental conditions. Moreover, PGE(2) and 17-phenyl trinor prostaglandin E(2) (a specific agonist of EP1 receptors) did not increase intracellular Ca(2+) concentration. Finally, PGE(2) did not affect the intracellular cAMP and did not reduce the isoproterenol dependent increase in cAMP. These results indicate that in HT-29 cells: (1) proliferation is not directly sensitive to PGE(2); and (2) PGE(2) does not stimulate a signal transduction pathway leading to intracellular increase in cAMP or Ca(2+) mobilization. Therefore, other cell lines should be used to assess the direct role played by prostanoids in promoting cell proliferation in colon cancer.


Assuntos
Adenocarcinoma/metabolismo , Cálcio/metabolismo , Neoplasias do Colo/metabolismo , AMP Cíclico/metabolismo , Dinoprostona/farmacologia , Adenocarcinoma/patologia , Anti-Inflamatórios não Esteroides/farmacologia , Bombesina/farmacologia , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Células HT29 , Humanos , Indometacina/farmacologia , Transdução de Sinais , Fatores de Tempo
7.
Oncol Rep ; 7(1): 183-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10601615

RESUMO

A variety of studies have supported the finding that regular intake of aspirin or non-steroidal anti-inflammatory drugs can affect colorectal cancer carcinogenesis by decreasing the synthesis of prostaglandins (PGs). We report that PG F2alpha, in the presence of indomethacin, did not stimulate the proliferation in HCT-8 and HT-29 human colon adenocarcinoma cells. Moreover, in both cell lines fluprostenol, a specific agonist of FP receptors, did not increase intracellular Ca2+ concentration, monitored with the fluorescent dye fura-2. These results indicate that in HCT-8 and HT-29 cells: i) proliferation is not sensitive to PG F2alpha; ii) functional FP receptors are absent. Therefore, either PG F2alpha is not necessarily involved in the proliferation of colorectal mucosa or cell lines other than HCT-8 and HT-29 should be used to assess the role played by PG F2alpha in promoting cell proliferation in colon cancer.


Assuntos
Adenocarcinoma/patologia , Neoplasias Colorretais/patologia , Dinoprosta/farmacologia , Adenocarcinoma/metabolismo , Cálcio/metabolismo , Divisão Celular/efeitos dos fármacos , Neoplasias Colorretais/metabolismo , Humanos , Células Tumorais Cultivadas
8.
Gen Pharmacol ; 32(2): 239-44, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10188626

RESUMO

The elevation of intracellular [Ca2+] induced by bradykinin (Bk) was monitored with fura-2 fluorescence in human skin fibroblasts. Neither [des-Arg10][Leu9]kallidin nor D-Arg[Hyp3,Thi5,D-Tic7,Oic8]bradykinin (HOE140) inhibited the Ca2+ response stimulated by Bk. Moreover, each behaved as a partial agonist causing the elevation of intracellular [Ca2+].


Assuntos
Antagonistas dos Receptores da Bradicinina , Bradicinina/metabolismo , Cálcio/metabolismo , Fibroblastos/efeitos dos fármacos , Adolescente , Antagonistas Adrenérgicos beta/farmacologia , Bradicinina/análogos & derivados , Bradicinina/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Humanos , Calidina/farmacologia , Masculino , Receptor B1 da Bradicinina , Receptor B2 da Bradicinina , Receptores da Bradicinina/metabolismo , Pele/efeitos dos fármacos , Pele/metabolismo
9.
Peptides ; 19(8): 1435-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9809659

RESUMO

The tachykinin-dependent stimulation of ion transport across frog skin was studied. Tachykinin stimulation was due to interaction with an NK1-like receptor as [Sar9-Met(O2)11]-Substance P (a very selective NK1 agonist) strongly stimulated SCC, whereas [beta-Ala8]-Neurokinin A 4-10 (a very selective NK2 agonist) did not. The rank order of tachykinin potency was: PG-KI > Uperolein > Hylambatin > Kassinin > Phyllomedusin > [Sar9-Met(O2)11]-Substance P > Ranatachykinin A > Physalaemin > Ranakinin > Substance P and Eledoisin >> Neurokinin A. Neurokinin B, Scyliorhinin I, Urechistachykinin I and Urechistachykinin II had no effect. We conclude that the minimal structural requirements for stimulating SCC in the frog skin were the presence of: a) the C-terminal sequence Phe-X-Gly-Leu-Met-NH2; b) at least one Pro residue in the N-terminal sequence.


Assuntos
Transporte de Íons/fisiologia , Rana esculenta/fisiologia , Fenômenos Fisiológicos da Pele , Taquicininas/fisiologia , Sequência de Aminoácidos , Animais , Taquicininas/química
10.
Arch Physiol Biochem ; 105(4): 329-36, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9711352

RESUMO

The effects of the non-mammalian tachykinin physalaemin were studied on the short circuit current (SCC) and on both influx (Ji) and outflux (Jo) of 36Cl- and 22Na+ across the isolated skin of Rana esculenta. Physalaemin, added to the internal bathing fluid, increased SCC in a dose-dependent manner with a maximal effect at 1 microM. This increase was due to a stimulation of both Na+ absorption and Cl- secretion. Bumetanide (20 microM in the internal fluid), an inhibitor of the Na+/K+/2Cl- cotransporter, reduced the action of physalaemin on SCC by 46%. Furthermore diphenylamine-2-carboxylic acid (DPC, 0.1 mM in the external fluid), an inhibitor of Cl- channels, decreased the effect of the peptide on SCC by 48%. It is concluded that physalaemin activates the Na+/K+/2Cl- cotransporter at the basolateral membrane, accumulating Cl- in the cells and favouring its exit through Cl- channels at the outermost membrane of the epithelium. An inhibitor of cyclooxygenases, i.e. naproxen, strongly inhibited the physalaemin effect on SCC, whereas 5,8,11-eicosatriynoic acid (ETI), an inhibitor of lipooxygenases was without effect. Therefore, it is proposed that prostaglandins (probably PGE2) are the cellular mediators of this action. An antagonist of NK1 receptors for tachykinins, CP 99,994, inhibited the physalaemin action on SCC, whereas challenge with SR 48,968, an antagonist of NK2 receptors, had no effect on physalaemin action. It is concluded that physalaemin effect on SCC in frog skin is mediated by its interaction with NK1 receptors.


Assuntos
Transporte de Íons/efeitos dos fármacos , Fisalemina/farmacologia , Pele/efeitos dos fármacos , Substância P/agonistas , Animais , Ácido Araquidônico/metabolismo , Técnicas In Vitro , Rana esculenta , Pele/metabolismo
11.
Arch Physiol Biochem ; 105(6): 596-602, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9587652

RESUMO

Cyclosporin A (Cs A), added to the fluid bathing the internal surface of the isolated skin of Rana esculenta, increased short-circuit current (SCC) with a maximal effect at 5 microM. This effect was completely inhibited by amiloride (0.2 mM in the fluid bathing the external surface). By measuring both transepithelial fluxes of 22Na+ across symmetrical parts of the short circuited skin, Cs A was found to increase the net absorption of Na+. Naproxen (10 microM), a cyclooxygenase inhibitor, decreased the stimulation by Cs A of SCC, suggesting that in this stimulation prostaglandins are involved. The Cs A effect on Na+ transport could be caused by an inhibition of a Ca2+/calmodulin-dependent protein phosphatase, i.e. calcineurin, since: a) it is mimicked by another inhibitor of calcineurin, i.e. fenvalerate: b) the action of Cs A and fenvalerate on SCC are decreased by the calmodulin inhibitor W7.


Assuntos
Ciclosporina/farmacologia , Pele/efeitos dos fármacos , Sódio/metabolismo , Amilorida/farmacologia , Animais , Calcineurina/fisiologia , Inibidores de Calcineurina , Cloretos/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Inibidores Enzimáticos/farmacologia , Transporte de Íons/efeitos dos fármacos , Naproxeno/farmacologia , Nitrilas , Piretrinas/farmacologia , Rana esculenta/metabolismo , Pele/metabolismo , Sulfonamidas/farmacologia
12.
Arch Physiol Biochem ; 104(2): 142-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8818196

RESUMO

Calcitonin gene-related peptide (CGRP) added to the internal fluid bathing the isolated skin of Rana esculenta strongly stimulates the active sodium absorption. This action is dose-dependent, the dose eliciting the maximal effect being 2 . 10(-7) M; alpha and beta CGRP exhibit the same potency. The CGRP action on sodium transport is mainly due to its interaction with CGRP1 receptors, since it is inhibited by CGRP8-37, its specific antagonist. The second messengers probably involved in the action of CGRP are cAMP and Ca+2, since this action is reduced by SQ22536 and W7, which are inhibitors of adenyl cyclase and calmodulin respectively. On the contrary, inhibitors of protein kinase C (1-O-hexadecyl-2-O-methyl-sn-glycerol) and nitric oxide synthase (L-NAME) do not modify the action on sodium transport. ETYA, an inhibitor of all the metabolic pathways of arachidonic acid, decreases the CGRP action by 38%. In order to search for the arachidonic acid metabolites involved in the CGRP action, the effect of the following inhibitors was tested: aspirin and naproxen (for cyclooxygenases), NDGA (for cyclooxygenases), NDGA (for lipoxygenases) clotrimazole (for epoxygenases). None of these substances is able to inhibit the CGRP action on sodium transport. Moreover, adding arachidonic acid inhibits the CGRP action, but this effect was also obtained by another unsaturated fatty acid, oleic acid. Since unsaturated fatty acids are able to inhibit the protein kinase A, these results indirectly support the role of cAMP as a second messenger of the CGRP action on sodium transport.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Absorção Cutânea/efeitos dos fármacos , Pele/efeitos dos fármacos , Sódio/farmacocinética , Animais , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Técnicas In Vitro , Rana esculenta , Pele/metabolismo
13.
Oncol Rep ; 3(6): 1161-3, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21594530

RESUMO

The intracellular mechanisms controlling cell proliferation in desmoid tumors (DT) are unknown. Bradykinin stimulated an increase in [Ca2+](i), (monitored by the fura-2 fluorescence) in fibroblasts obtained from both the skin of a normal donor and the mesenter of a familial adenomatous polyposis (FAP) patient. Cells from DT of the same patient as well as those from another FAP patient failed to show the elevation of [Ca2+](i) usually caused by bradykinin stimulation.

14.
Arch Physiol Biochem ; 103(4): 492-6, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8548488

RESUMO

In the last five years, several measurements of 22Na+ influx (Ji) and outflux (Jo) across symmetrical parts of the isolated skin of Rana esculenta, under permanent short circuitation, were performed in our Institute. The mean value of the 22Na+ net fluxes (Ji-Jo) exceeded the mean value of the short circuit current measurements (1.14 +/- 0.04 versus 0.98 +/- 0.02 microE.cm-2.h-1, 253 experiments). Since this discrepancy could be due to a concomitant Cl- net absorption, 36Cl- unidirectional fluxes were detected under similar experimental conditions. The Cl- net flux mean value was 0.11 +/- 0.02 microE.cm-2.h-1 (316 experiments) which accounts for 70% of the discrepancy between the Na+ net flux and short circuit current. This Cl- net absorption occurred in the absence of electrochemical gradients and was very likely maintained by a Na+/K+/2Cl- cotransport located at the outermost membrane of the epithelium. In fact bumetanide challenge (10(-5) M in the external fluid) strongly inhibited 36Cl- influx and 22Na+ influx across this tissue and cleared off the discrepancy between short circuit current and sodium net flux.


Assuntos
Cloretos/farmacocinética , Absorção Cutânea/fisiologia , Sódio/farmacocinética , Amilorida/farmacologia , Animais , Bumetanida/farmacologia , Diuréticos/farmacologia , Técnicas In Vitro , Transporte de Íons/efeitos dos fármacos , Rana esculenta , Absorção Cutânea/efeitos dos fármacos
15.
Arch Int Physiol Biochim Biophys ; 102(6): 315-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7534500

RESUMO

Dopamine addition to the internal fluid bathing the isolated frog skin results in a strong increase of short circuit current (SCC) across this tissue. The effect is dose-dependent, 10(-4) M being the dose resulting in maximal effect. The measure of transepithelial fluxes of both 22Na+ and 36Cl- across symmetrical parts of skin short-circuited in permanence demonstrates that this effect is due to stimulation of Na+ adsorption and Cl- secretion. The former effect, but not the latter one, is mimicked by both SKF89124A and SKF82525J (D1 and D2 agonists, respectively). Moreover the effect of dopamine on SCC and Na+ net flux is wider than that of its synthetic agonists even when both D1 and D2 agonists were added together. It is suggested that the extraeffect of dopamine on SCC is due to a stimulation of Cl- secretion, probably mediated by dopamine interaction with another receptor.


Assuntos
Dopamina/farmacologia , Canais Iônicos/efeitos dos fármacos , Pele/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Cloretos/metabolismo , Dopamina/administração & dosagem , Agonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Condutividade Elétrica , Fenoldopam/farmacologia , Indóis/farmacologia , Canais Iônicos/fisiologia , Rana esculenta , Pele/efeitos dos fármacos , Sódio/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-7516733

RESUMO

Capsaicin at low concentrations increases the short circuit current (SCC) across frog skin. Simultaneous measurements of both transepithelial fluxes of 22Na or 36Cl demonstrate that the SCC increase is due to stimulation of sodium active absorption. Capsaicin acts through the liberation of several peptides; thus these peptides were tested on the SCC across frog skin. Those more active are, in order of potency: Cyclic Calcitonin Gene Related Peptide (CGRP), Kassinin and Eledoisin, Substance P (SP) and Neurokinin A. Neurokinin B and Vasoactive Intestinal Peptide (VIP) have no effect. Also the actions of SP and CGRP are due mainly to stimulation of Na+ active absorption. A strict parallelism regarding the sensitivity to inhibitors (Naproxen, SQ22536 and CP96345) between SP, CGRP and Capsaicin strengthens the hypothesis that SP and CGRP are liberated by Capsaicin in this tissue.


Assuntos
Capsaicina/farmacologia , Fenômenos Fisiológicos da Pele , Sódio/metabolismo , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Condutividade Elétrica , Eledoisina/farmacologia , Epitélio/efeitos dos fármacos , Epitélio/fisiologia , Cassinina/farmacologia , Neurocinina A/farmacologia , Rana esculenta , Pele/efeitos dos fármacos , Substância P/farmacologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-1360392

RESUMO

1. The pesticide carbaryl induces Cl- secretion through the isolated frog skin. 2. This effect is due to the activation of both processes responsible for this phenomenon: (a) Na+/K+/2Cl- cotransport on the serosal membrane; (b) Cl- selective channels on the external membrane. 3. Cl- outflux is inhibited by bumetanide (10(-5) M) on the serosal side and by diphenylamine-2-carboxylic acid (DPC) (10(-3) M) on the external side. 4. The DPC action is not mimicked by Naproxen, a specific inhibitor of cyclooxygenase. 5. A comparison with isoprenaline, demonstrates that the carbaryl action is, paradoxically, more selective than that of isoprenaline. 6. This selectivity of carbaryl action on Cl- permeability is confirmed by the fact that, unlike isoprenaline, carbaryl does not affect the permeability of Na+ and thiourea.


Assuntos
Carbaril/farmacologia , Cloretos/metabolismo , Pele/efeitos dos fármacos , Pele/metabolismo , Animais , Bumetanida/farmacologia , Proteínas de Transporte/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Canais de Cloreto , Isoproterenol/farmacologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Rana esculenta , Simportadores de Cloreto de Sódio-Potássio , ortoaminobenzoatos/farmacologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-1354117

RESUMO

1. Isoprenaline strongly increases the urea permeability of the bladder of Bufo bufo. This effect is due to its interaction with beta 2-adrenoreceptors, activating, in turn, the adenyl cyclase. 2. In order to ensure the regulation of urea permeability, the isoprenaline effect is present even in pathophysiological conditions, inhibiting the vasopressin action.


Assuntos
Permeabilidade da Membrana Celular/fisiologia , Receptores Adrenérgicos beta/fisiologia , Ureia/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Inibidores de Adenilil Ciclases , Adenilil Ciclases/metabolismo , Agonistas alfa-Adrenérgicos/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Albuterol/farmacologia , Animais , Bufo bufo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Fenoterol/farmacologia , Isoproterenol/farmacologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-1711430

RESUMO

1. The effects of both adenyl cyclase inhibitors (MDL12330A and SQ22536) have been studied on the ionic transport induced by vasopressin and isoprenaline across the frog skin. 2. MDL12330A inhibits the vasopressin action on the short-circuit current (SCC), confirming that this effect is cAMP-mediated. 3. On the other hand, isoprenaline action on the SCC is unaffected by MDL12330A. However, this lack of effect is not a sufficient argument against the role of cAMP in this action; in fact, as MDL12330A is also an inhibitor of cAMP phosphodiesterase, this action could mask the inhibitory effect of the drug on adenyl cyclase. 4. By using the other adenyl cyclase inhibitor (SQ22536), probably deprived of effect on the cAMP phosphodiesterase, we obtained a strong inhibition of isoprenaline action on the SCC. Thus we conclude that the actions of isoprenaline on the ionic transport across the frog skin are also cAMP-mediated.


Assuntos
Adenina/análogos & derivados , Inibidores de Adenilil Ciclases , Iminas/farmacologia , Isoproterenol/farmacologia , Pele/metabolismo , Vasopressinas/farmacologia , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Adenina/farmacologia , Amilorida/farmacologia , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Cloretos/metabolismo , AMP Cíclico/fisiologia , Condutividade Elétrica , Canais Iônicos/efeitos dos fármacos , Canais Iônicos/metabolismo , Rana esculenta , Sódio/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-1981345

RESUMO

1. Carbaryl, a carbamate used as a pesticide, increases the short-circuit current (SCC) across the isolated frog skin in a dose-dependent manner. 2. This effect is due to the stimulation of sodium absorption and chloride secretion. 3. Carbaryl action on short-circuit current is unrelated to its inhibitory power on cholinesterase; this statement is supported by two experimental results: (a) carbaryl is equally active on both sides of the skin, (b) atropine pretreatment does not inhibit the carbaryl action on SCC.


Assuntos
Carbaril/farmacologia , Cloretos/metabolismo , Fenômenos Fisiológicos da Pele , Sódio/metabolismo , Animais , Atropina/farmacologia , Transporte Biológico/efeitos dos fármacos , Técnicas In Vitro , Cinética , Potenciais da Membrana/efeitos dos fármacos , Rana esculenta , Pele/efeitos dos fármacos
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