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1.
Reprod Domest Anim ; 52 Suppl 2: 275-280, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27885720

RESUMEN

Since the conclusion of data collation from previously published work, a further 352 inseminations using frozen-thawed dog semen by endoscopic-assisted transcervical insemination (EIU) have been performed by the author. Insemination was performed on the second day in which crenulation of the anterior vagina was detected in conjunction with a progesterone concentration of >10 ng/ml. All semen samples were analysed for total number of sperm, total motility and progressive motility using computer-assisted semen analysis (CASA). The insemination dose was based on the progressively motile normal spermatozoa (PMNS). Insemination was performed on all bitches as previously described using a ureterorenoscope. Additional extender was inseminated subsequent to the semen to expand and fill the uterus. The semen and additional extender were inseminated slowly over a period of 15-20 min. Pregnancy was determined by B-mode ultrasound equipped with a 7.5-MHz probe whilst standing and/or via the whelping rate. The number of sperm inseminated ranged from 9 × 106 PMNS to 519 × 106 PMNS, with progressive motility values ranging between 20% and 80%. The overall pregnancy rate was 68% (238/352). When stratified by PMNS, pregnancy rates were as follows: >150 × 106 PMNS - 76% (110/145), 100-150 × 106 - 68% (87/128) and <100 × 106 PMNS - 52% (41/79). Pregnancy rate was significantly higher when >150 × 106 PMNS (p = .003) or 100-150 ×106 PMNS (p = .027) were inseminated compared to <100 × 106 PMNS. These data are concordant with previous reports recommending the insemination of >150 × 106 PMNS to maximize pregnancy rate. These results indicate that one optimally timed EIU insemination results in similar pregnancy rates to previous publications of one optimally timed, or two or more non-optimally timed inseminations using the Norwegian catheter.


Asunto(s)
Perros , Endoscopía/veterinaria , Inseminación Artificial/veterinaria , Preservación de Semen/veterinaria , Animales , Endoscopía/métodos , Femenino , Calor , Inseminación Artificial/métodos , Masculino , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Análisis de Semen/métodos , Análisis de Semen/veterinaria , Recuento de Espermatozoides , Motilidad Espermática , Uréter
2.
BMC Genet ; 17: 56, 2016 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-27044251

RESUMEN

BACKGROUND: Residual biomass production for fuel conversion represents a unique opportunity to avoid concerns about compromising food supply by using dedicated feedstock crops. Developing tomato varieties suitable for both food consumption and fuel conversion requires the establishment of new selection methods. RESULTS: A tomato Solanum pennellii introgression population was assessed for fruit yield, biomass phenotypic diversity, and for saccharification potential. Introgression lines 2-5, 2-6, 6-3, 7-2, 10-2 and 12-4 showed the best combination of fruit and residual biomass production. Lignin, cellulose, hemicellulose content and saccharification rate showed a wide variation in the tested lines. Within hemicellulose, xylose value was high in IL 6-3, IL 7-2 and IL 6-2, whereas arabinose showed a low content in IL 10-2, IL 6-3 and IL 2-6. The latter line showed also the highest ethanol potential production. Alkali pre-treatment resulted in the highest values of saccharification in most of lines tested, suggesting that chemical pretreatment is an important factor for improving biomass processability. Interestingly, extreme genotypes for more than one single trait were found, allowing the identification of better genotypes. Cell wall related genes mapping in genomic regions involved into tomato biomass production and digestibility variation highlighted potential candidate genes. Molecular expression profile of few of them provided useful information about challenged pathways. CONCLUSIONS: The screening of S. pennellii introgression population resulted very useful for delving into complex traits such as biomass production and digestibility. The extreme genotypes identified could be fruitfully employed for both genetic studies and breeding.


Asunto(s)
Biomasa , Frutas/genética , Fenotipo , Solanum/genética , Celulosa/análisis , Cromosomas de las Plantas , Productos Agrícolas/genética , Etanol/metabolismo , Frutas/química , Lignina/análisis , Pectinas/análisis , Polisacáridos/análisis , Sitios de Carácter Cuantitativo , Solanum/química , Transcriptoma
3.
Nature ; 439(7076): 576-9, 2006 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-16452977

RESUMEN

The control of epidemic malaria is a priority for the international health community and specific targets for the early detection and effective control of epidemics have been agreed. Interannual climate variability is an important determinant of epidemics in parts of Africa where climate drives both mosquito vector dynamics and parasite development rates. Hence, skilful seasonal climate forecasts may provide early warning of changes of risk in epidemic-prone regions. Here we discuss the development of a system to forecast probabilities of anomalously high and low malaria incidence with dynamically based, seasonal-timescale, multi-model ensemble predictions of climate, using leading global coupled ocean-atmosphere climate models developed in Europe. This forecast system is successfully applied to the prediction of malaria risk in Botswana, where links between malaria and climate variability are well established, adding up to four months lead time over malaria warnings issued with observed precipitation and having a comparably high level of probabilistic prediction skill. In years in which the forecast probability distribution is different from that of climatology, malaria decision-makers can use this information for improved resource allocation.


Asunto(s)
Clima , Malaria/epidemiología , Modelos Biológicos , Estaciones del Año , Animales , Botswana/epidemiología , Culicidae/fisiología , Humanos , Incidencia , Malaria/parasitología , Malaria/prevención & control , Probabilidad , Lluvia , Factores de Riesgo , Temperatura , Factores de Tiempo , Tiempo (Meteorología)
4.
Sci Rep ; 11(1): 3425, 2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33564080

RESUMEN

Cellulosic ethanol derived from fast growing C4 grasses could become an alternative to finite fossil fuels. With the potential to generate a major source of lignocellulosic biomass, maize has gained importance as an outstanding model plant for studying the complex cell wall network and also to optimize crop breeding strategies in bioenergy grasses. A genome-wide association study (GWAS) was conducted using a subset of 408 Recombinant Inbred Lines (RILs) from a Multi-Parent Advanced Generation Intercross (MAGIC) Population in order to identify single nucleotide polymorphisms (SNPs) associated with yield and saccharification efficiency of maize stover. We identified 13 SNPs significantly associated with increased stover yield that corresponded to 13 QTL, and 2 SNPs significantly associated with improved saccharification efficiency, that could be clustered into 2 QTL. We have pointed out the most interesting SNPs to be implemented in breeding programs based on results from analyses of averaged and yearly data. Association mapping in this MAGIC population highlight genomic regions directly linked to traits that influence the final use of maize. Markers linked to these QTL could be used in genomic or marker-assisted selection programs to improve biomass quality for ethanol production. This study opens a possible optimisation path for improving the viability of second-generation biofuels.

5.
Science ; 189(4202): 561-3, 1975 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-1145213

RESUMEN

Duffy blood group negative human erythrocytes (FyFy) are resistant to infection by Plasmodium knowlesi, a simian malaria that infects Duffy positive human erythrocytes. The P. knowlesi resistance factor, Duffy negative erythrocytes, occurs in high frequency in West Africa, where the people are resistant to vivax malaria. This suggests that Duffy blood group determinants (Fya or Fyb) may be erythrocyte receptors for P. vivax.


Asunto(s)
Antígenos de Grupos Sanguíneos , Eritrocitos/metabolismo , Malaria/sangre , Plasmodium/metabolismo , Sitios de Unión , Quimotripsina , Eritrocitos/inmunología , Genotipo , Homocigoto , Humanos , Malaria/parasitología , Plasmodium/inmunología , Pronasa , Grabación de Cinta de Video
6.
J Neurol Neurosurg Psychiatry ; 79(5): 500-3, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17846114

RESUMEN

We investigated the utility of the Cambridge Behavioural Inventory (CBI), a carer-completed questionnaire, in a large cohort with Parkinson's disease (PD) (n = 215). In a sub-cohort of 112 patients with PD, the CBI was found to be a valid instrument compared with the Neuropsychiatric Inventory, PDQ-39 and UPDRS, with high internal consistency. Furthermore, in the whole cohort, the CBI was sensitive to changes in behaviour with disease progression. Comparison between CBI scores in PD and other neurodegenerative diseases, including Huntington's disease (HD) (n = 75), Alzheimer's disease (AD) (n = 96) and frontal variant frontotemporal dementia (fvFTD) (n = 64), revealed distinct profiles for each disease. Predominant deficits were "sleep"' and "self care" in PD; "memory" in HD and AD; and "motivation" and "stereotypic behaviours" in fvFTD. The CBI is a robust, easy-to-use and valid instrument, which has the capacity to discriminate between neurodegenerative diseases, and may be of value in monitoring therapeutic interventions.


Asunto(s)
Trastornos Mentales/diagnóstico , Enfermedad de Parkinson/diagnóstico , Encuestas y Cuestionarios , Actividades Cotidianas/clasificación , Actividades Cotidianas/psicología , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Análisis de Varianza , Cuidadores/psicología , Estudios de Cohortes , Demencia/diagnóstico , Demencia/psicología , Diagnóstico Diferencial , Evaluación de la Discapacidad , Progresión de la Enfermedad , Femenino , Humanos , Enfermedad de Huntington/diagnóstico , Enfermedad de Huntington/psicología , Masculino , Trastornos Mentales/psicología , Escala del Estado Mental/estadística & datos numéricos , Persona de Mediana Edad , Enfermedad de Parkinson/psicología , Psicometría/estadística & datos numéricos , Calidad de Vida/psicología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
Br J Pharmacol ; 103(3): 1649-56, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1718521

RESUMEN

1 The role of extracellular nucleotides in regulation of ion transport activities (short circuit current, Isc) of human respiratory epithelia was studied. 2 Application of nucleotides to the apical or basolateral membrane of human nasal epithelium induced a concentration-dependent increase in Isc. 3 The rank order of potency of purine- or pyrimidine-induced changes in Isc of normal human nasal epithelium when applied to the apical membrane (UTP greater than or equal to ATP greater than ATP gamma S greater than 2MeSATP greater than ADP beta S much greater than beta gamma MeATP greater than or equal to alpha beta MeATP) or basolateral membrane (2MeSATP greater than UTP greater than ATP greater than ATP gamma S greater than alpha beta MeATP greater than beta gamma MeATP) is consistent with involvement of a P2 purinoceptor. A similar rank order of potencies was observed for nucleotide effects on intracellular calcium measured by Fura-2 fluorescence using microspectrofluorimetry. 4 Similar nucleotide potency in the regulation of ion transport and intracellular calcium in cystic fibrosis (CF) airway epithelium (UTP greater than or equal to ATP) was observed, suggesting purinoceptors might be used to stimulate ion transport processes that would promote hydration of airway secretions and facilitate their clearance from CF lungs. 5 These data provide evidence for the regulation of ion transport by P2 purinoceptors in normal and cystic fibrosis human airway epithelium.


Asunto(s)
Adenosina Trifosfato/fisiología , Calcio/metabolismo , Fibrosis Quística/metabolismo , Canales Iónicos/metabolismo , Cloruros/metabolismo , Electrofisiología , Epitelio/metabolismo , Epitelio/fisiología , Humanos , Técnicas In Vitro , Canales Iónicos/fisiología , Mucosa Nasal/citología , Mucosa Nasal/efectos de los fármacos , Mucosa Nasal/metabolismo , Nucleótidos/farmacología , Receptores Purinérgicos/efectos de los fármacos , Receptores Purinérgicos/metabolismo
8.
Br J Pharmacol ; 106(4): 774-82, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1327386

RESUMEN

1. We have characterized an adenosine receptor subtype present in human airway epithelial cells by measuring the changes in the intracellular levels of adenosine 3':5'-cyclic monophosphate (cyclic AMP) and the rate of transepithelial Cl- secretion. 2. Primary cultures of human nasal epithelium obtained from excised surgical airway epithelial tissues and the cell lines BEAS39 and CF/T43 derived from human airway epithelium were grown on plastic dishes and labelled with [3H]-adenine for measurement of intracellular cyclic AMP accumulation. Primary cultures were loaded with the calcium indicator fura-2 to measure [Ca2+]i and studied as polarized, ion transporting epithelia on collagen matrix supports for measurement of Cl- secretion. 3. Adenosine analogues stimulated cyclic AMP accumulation with a rank order of potency characteristic of an A2-receptor: 5-N-ethyl-carboxamidoadenosine (NECA) greater than adenosine greater than R-phenylisopropyladenosine (R-PIA), 6-N-cyclopentyladenosine (CPA) greater than S-PIA. NECA increased cyclic AMP accumulation in normal and cystic fibrosis (CF) primary cells as well as in the CF/T43 and BEAS39 cell lines with K0.5 values ranging from 0.3 to 3 microM. Preincubation with NECA resulted in the homologous desensitization of airway epithelial cells. The effect of NECA was specifically inhibited by the adenosine receptor antagonist, aminophylline, in a competitive manner. 4. The A1-adenosine receptor agonists CPA and R-PIA did not inhibit isoprenaline-stimulated cyclic AMP accumulation in CF/T43 cells, and potentiating effects of the adenosine analogues were observed on forskolin-stimulated cyclic AMP accumulation. Adenosine analogues did not cause significant changes in intracellular Ca2+ ([Ca2+]i) in airway epithelium.5. Adenosine analogues, applied to either the serosal or mucosal side of the polarized amiloride pretreated primary cultures, induced changes in I,, with a rank order of potency of agonists similar to that observed for stimulation of cyclic AMP accumulation. Intracellular microelectrode studies indicated that the locus of action was the apical membrane Cl- conductance. Adenosine failed to stimulate C1- secretion in CF airway epithelium.6. These results provide evidence for the existence of an A2-adenosine receptor that modulates intracellular levels of cyclic AMP in human airway epithelium. Activation of this receptor might lead to stimulation of Cl- secretion in amiloride pretreated normal but not CF cells.


Asunto(s)
Cloruros/metabolismo , Receptores Purinérgicos/fisiología , Sistema Respiratorio/química , Adenosina/análogos & derivados , Adenosina/farmacología , Aminofilina/farmacología , Calcio/análisis , Células Cultivadas , Colforsina/farmacología , AMP Cíclico/análisis , AMP Cíclico/fisiología , Epitelio/química , Humanos , Receptores Purinérgicos/análisis , Tritio
9.
Insect Biochem Mol Biol ; 33(2): 229-38, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12535681

RESUMEN

Spider dragline silk is renowned as one of the toughest materials of its kind. In nature, spider silks are spun out of aqueous solutions under environmental conditions. This is in contrast to production of most synthetic fibres, where hazardous solvents, high temperatures and pressure are used. In order to identify some of the chemical processes involved in spider silk spinning, we have produced a collection of cDNA sequences from specific regions of Nephila senegalensis major ampullate gland. We examined in detail the sequence and expression of a putative Nephila senegalensis peroxidase gene (NsPox) from our EST collection. NsPox encodes a protein with similarity to Drosophila melanogaster and Aedes aegypti peroxidases. Northern analysis and in situ localisation experiments revealed that NsPox is expressed in major and minor ampullate glands of the spider where the main components of the dragline silk are produced. We suggest that NsPox plays a role in dragline silk fibre formation and/or processing.


Asunto(s)
Proteínas de Insectos/genética , Peroxidasas/genética , Arañas/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ADN Complementario , Drosophila melanogaster/enzimología , Drosophila melanogaster/genética , Etiquetas de Secuencia Expresada , Biblioteca de Genes , Hibridación in Situ , Datos de Secuencia Molecular , Peroxidasas/química , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Seda , Arañas/genética
10.
Am J Trop Med Hyg ; 26(2): 195-7, 1977 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-403820

RESUMEN

It has been observed that a surface coat, 20 nm in thickness, extends from the plasma membrane of extracellular merozoites and that this coat contains strain-specific antigens. In the present study we determined the possible effect of protein in the culture medium on this structure. The surface coat on merozoites in culture medium devoid of protein was indistinguishable by transmission electron microscopy from the coat in a protein-containing medium. This supports the hypothesis that the surface coat originates from the parasite rather than from adsorbed serum protein.


Asunto(s)
Malaria/patología , Plasmodium/ultraestructura , Animales , Membrana Celular/parasitología , Membrana Celular/ultraestructura , Medios de Cultivo , Eritrocitos/parasitología , Eritrocitos/ultraestructura , Haplorrinos , Macaca mulatta , Malaria/parasitología , Proteínas
11.
Avian Dis ; 28(3): 751-7, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6487195

RESUMEN

A major epornitic of Mycoplasma gallisepticum occurred in the Monroe, North Carolina, area between January and June of 1983. The outbreak involved 304,000 turkeys of various ages, which were slaughtered in the eradication program at a cost of more than $550,000 to growers and poultry companies. An infected peafowl was the likely source of infection on the first farm. Traffic between farms by growers and company personnel was theorized to be the means of further spread.


Asunto(s)
Brotes de Enfermedades/veterinaria , Infecciones por Mycoplasma/veterinaria , Enfermedades de las Aves de Corral/epidemiología , Pavos , Animales , Femenino , Masculino , Infecciones por Mycoplasma/economía , Infecciones por Mycoplasma/epidemiología , North Carolina , Enfermedades de las Aves de Corral/economía
12.
Theriogenology ; 82(6): 844-50, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25082020

RESUMEN

The objective of this retrospective clinical study was to compare pregnancy rates obtained after the use of endoscopic-assisted transcervical catheterization (EIU) or laparotomy (SIU) for insemination of frozen-thawed dog semen. Healthy bitches from various breeds were inseminated with semen from multiple donors processed by different freezing centers. Data from 118 inseminations (78 EIU and 40 SIU) performed between 2009 and 2011 were analyzed. Insemination timing was based on vaginal cytology, serum progesterone concentrations, and vaginoscopy. A ureterorenoscope and a CH-5 Transcervical insemination catheter were used for EIU; 28 of the bitches in this group were inseminated twice with the second insemination less than 12 hours after the first. The numbers of live morphologically normal sperm (LMNS) were determined to characterize insemination doses. Overall, pregnancy rate was greater (P < 0.05) in the EIU group (65%) than in the SIU group (45%). Pregnancy rates were greater (P ≤ 0.06) when more than 100 × 10(6) LMNS were inseminated regardless of insemination method; the greatest pregnancy rate was observed in the EIU group when this insemination dose was used (38/49; 78%). There was no significant difference in pregnancy rate whether one (69%) or two inseminations (64%) were performed in the EIU group. Complications in the SIU group included anesthetic-induced bradycardia during surgery, significant postsurgery pain, seroma formation over the abdominal incision, and delayed wound healing. No complications were noted during or after insemination in the EIU group. In conclusion, these results support the use of EIU as a noninvasive alternative to laparotomy for insemination of frozen-thawed dog semen. In addition, use of more than 100 × 10(6) LMNS is also recommended for insemination.


Asunto(s)
Perros/fisiología , Histeroscopía/veterinaria , Inseminación Artificial/veterinaria , Laparotomía/veterinaria , Preservación de Semen/veterinaria , Semen/fisiología , Animales , Femenino , Congelación , Inseminación Artificial/métodos , Masculino , Embarazo , Estudios Retrospectivos
17.
J Plant Res ; 121(5): 527-34, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18615263

RESUMEN

The aim of this study was to measure key material properties of the cell walls of single suspension-cultured plant cells and relate these to cell-wall biochemistry. To this end, micromanipulation was used to compress single tomato cells between two flat surfaces until they ruptured, and force-deformation data were obtained. In addition to measuring the bursting force, we also determined the elastic (Young's) modulus of the cell walls by matching low strain (< or = 20% deformation) experimental data with a cell compression model, assuming linear elastic cell walls. The walls were most elastic at pH 4.5, the pH optimum for expansin activity, with an elastic modulus of 2.0 +/- 0.1 GPa. Following the addition of exogenous expansins, cell walls became more elastic at all pH values. Western blot analysis of proteins from walls of cultured cells revealed the presence of expansin epitopes, suggesting that the inherent pH dependence of elasticity and other compression phenomena is related to the presence of endogenous expansin proteins and their wall-loosening ability. Although strict application of the linear-elastic model could not be applied to large deformations-for example, up to cell bursting-because of irreversible behaviour, the deviation of the data from the model was generally small enough to allow estimation of the strain in the cell wall at failure. This strain was greater at pH 4.5 and when expansins were added to the suspension. The changes in elasticity are consistent with suggestions about the mode of expansin action. The estimated strains at failure are compatible with data on the failure of Acetobacter-derived cellulose-xyloglucan composites and proposed mechanisms of such failure. Through the measurement of cell-wall material properties using micromanipulation, it may be possible to understand more fully how cell-wall composition, structure and biochemistry lead to cell mechanical behaviour.


Asunto(s)
Pared Celular/fisiología , Proteínas de Plantas/fisiología , Solanum lycopersicum/citología , Fenómenos Biomecánicos , Técnicas de Cultivo de Célula , Células Cultivadas , Concentración de Iones de Hidrógeno , Solanum lycopersicum/fisiología , Modelos Biológicos
18.
Prog Cardiovasc Dis ; 21(2): 119-32, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-150620

RESUMEN

Echocardiography is a valuable technique for the diagnosis and serial follow-up of patients with impaired cardiac function. It is subject to certain limitations due to the assumptions inherent in deriving ventricular volume from a one-dimensional measurement and must be interpreted with caution in cases of suspected regional abnormalities of contraction. Given these caveats, echocardiography is valuable in the quantitative assessment of cardiac size and the level of compensation in patients with primary myocardial disease, valvular heart disease, and left ventricular hypertrophy. It can detect abnormal contraction in some patients with ischemic heart disease and provides an accurate method to serially follow changes produced as a result of drug or surgical therapy. Finally, two-dimensional techniques promise to provide a new perspective on the evaluation of patients with regional wall motion abnormalities.


Asunto(s)
Ecocardiografía , Cardiopatías/diagnóstico , Corazón/fisiología , Volumen Cardíaco , Cardiomegalia/diagnóstico , Cardiomiopatías/diagnóstico , Enfermedad Coronaria/diagnóstico , Ecocardiografía/métodos , Corazón/efectos de los fármacos , Insuficiencia Cardíaca/diagnóstico , Enfermedades de las Válvulas Cardíacas/diagnóstico , Hemodinámica/efectos de los fármacos , Humanos , Contracción Miocárdica , Función Ventricular
19.
J Clin Gastroenterol ; 3(2): 115-20, 1981 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7240686

RESUMEN

We report two patients with quinidine-induced esophagitis along with a review which reveals drug-induced esophagitis to be uncommon. Certain drugs implicated time and again include tetracycline, doxycycline KCl, quinidine, clindamycin, and a British drug, emepronium. Other drugs are mentioned in isolated case reports. Most patients have a benign course, responding well to antacids and discontinuation of the responsible medication, with the exception of KCl-induced injury, which may be fatal. Taking medication with a drink of water and avoiding medications just before retiring may help prevent drug-induced esophagitis.


Asunto(s)
Esofagitis/inducido químicamente , Anciano , Clindamicina/efectos adversos , Doxiciclina/efectos adversos , Emepronio/efectos adversos , Humanos , Masculino , Cloruro de Potasio/efectos adversos , Quinidina/efectos adversos , Tetraciclinas/efectos adversos
20.
Nature ; 377(6550): 643-6, 1995 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-7566178

RESUMEN

Epithelial cells exist in a complex setting in which responses to mucosal or serosal environments are mediated by receptors expressed on specialized cellular domains, such as apical versus basolateral cell membranes. We investigated whether airway epithelia can react selectively through G-protein-coupled receptors to stimuli in the mucosal or serosal environments by measuring inositol phosphate and intracellular Ca2+ responses in polarized human nasal epithelial monolayers. We report here that unilateral ATP (10(-4) M) administration stimulated P2 purinoceptors and tapped pools of intracellular Ca2+ associated with the plasma membrane ipsilateral but not contralateral to stimulated receptors. Similarly, activation of plasma membrane Ca2+ influx by ATP was confined to the membrane ipsilateral to receptor stimulation. These findings demonstrate that polarized epithelia restrict P2 receptor-mediated responses to a single domain of the cell, reflecting membrane-specific generation and catabolism of inositol phosphates and confinement of calcium influx regulation to the membrane ipsilateral to the stimulated receptors.


Asunto(s)
Calcio/metabolismo , Membrana Celular/metabolismo , Polaridad Celular , Epitelio/metabolismo , Mucosa Nasal/metabolismo , Adenosina Trifosfato/metabolismo , Células Cultivadas , Humanos , Fosfatos de Inositol/metabolismo , Mucosa Nasal/citología , Receptores Purinérgicos P2/metabolismo
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