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1.
Pol J Vet Sci ; 21(2): 265-272, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30450864

RESUMEN

Lipogranulomas are lesions found in histopathological liver examination in humans and in various animal species, including dogs, especially those with portosystemic shunts. They consist of macrophages and other inflammatory cells, and sometimes they contain iron salts (pigment granuloma). This study aimed at determining the number of granulomas and cellular composition of lipogranulomas in dogs with the congenital extrahepatic portosystemic shunt, and to identify factors associated with their development. 44 archival liver samples from dogs with portosystemic shunt were stained using HE, Perl's method and - in randomly-selected cases - immunohistochemically against CD56, CD20 and CD3 (DAKO). A reduction in the size of the liver was observed in all dogs during laparotomy, and the diameter of the vessel circumventing the liver was also measured (in 24 dogs). Lipogranulomas were found in 52.3% of samples; iron salts were present in 47.8% of them; 72% of cells in lipogranulomas were macrophages. In lipogranulomas both types of lymphocytes - T and B - were seen. The presence of lipogranulomas in liver samples in dogs was connected with fatty degeneration of hepatocytes and was correlated with the age of animals and with the diameter of the abnormal vessel circumventing the liver. Their formation appears to be triggered by severe ischemia and shortage of nutrient supply.


Asunto(s)
Enfermedades de los Perros , Granuloma , Hígado , Animales , Perros , Granuloma/veterinaria , Hígado/patología , Linfocitos , Derivación Portosistémica Quirúrgica
2.
J Fish Dis ; 40(7): 873-884, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27690267

RESUMEN

Kynurenic acid (KYNA) is an endogenous substance produced on the kynurenine pathway which is primarily known for its neuroactive properties. Recently, it has been proven that KYNA is a selective ligand for G protein-coupled receptor (GPR 35), presented on immunocompetent cells such as T lymphocytes. This opens up new possibilities of its application as an immunostimulating substance in aquaculture. Thus far, no histopathological investigations in fish have been completed to evaluate influence of KYNA supplementation in feed. This study has been undertaken to determine the effect of feed supplementation with KYNA (2.5, 25, 250 mg kg-1 of feed) for 28 days on the liver, gills and kidney in healthy fish and experimentally infected with Yersinia ruckeri. In a control group were observed a fatty liver, which is natural for this fish species in the autumn and winter season. As the dose of the supplement was increased, the fat liver changed, it decreased or completely disappeared. Additionally, inflammatory changes occurred in all the analysed organs, and their intensification was dose dependent. In the fish experimentally infected, KYNA caused aggravation of the signs in the liver, kidneys and gills, and the effect was dose dependent. The results implicate that KYNA may be a stressor for fish.


Asunto(s)
Dieta/veterinaria , Suplementos Dietéticos , Enfermedades de los Peces/inmunología , Ácido Quinurénico , Oncorhynchus mykiss , Yersiniosis/veterinaria , Yersinia ruckeri/fisiología , Adyuvantes Inmunológicos , Alimentación Animal/análisis , Animales , Relación Dosis-Respuesta a Droga , Enfermedades de los Peces/microbiología , Branquias/patología , Riñón/patología , Hígado/patología , Yersiniosis/inmunología , Yersiniosis/microbiología
3.
Pol J Vet Sci ; 20(2): 233-240, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28865209

RESUMEN

The most popular rainbow trout (Oncorhynchus mykiss, Walbaum 1792) production technologies include both an extensive method with the flow through system (FTS) and an intensive method with the recirculating aquaculture system (RAS). Their impact on the fish was evaluated with a morphological assessment of the gills, as these are organs susceptible to environmental changes. Trout of 350 - 500 g body mass were caught for trial in spring and autumn, with 36 fish originating from 3 fish farms with the FTS system and an equal number from 3 RAS fish farms (n = 6). The fish were macroscopically examined and the gills were investigated microscopically (haematoxylin and eosin staining). Hypertrophy and hyperplasia were most commonly detected, amounting to 89% of all structural abnormalities. These lesions were slightly more common in the FTS, especially in autumn, whereas the changes to the blood vessels in the gills were observed more frequently in the rainbow trout from the RAS system than in the fish obtained from the FTS technology (the difference was statistically significant). The morphological lesions in the mucous cells of the gills were detected at a comparable severity regardless of the technology or production season. The predominantly low values of the histopathologic indices, which described the microscopic lesions in the gills of fish from the FTS and RAS systems, showed that the examined organ was most often free of lesions or demonstrated only minor morphological damage regardless of the production technology.


Asunto(s)
Crianza de Animales Domésticos/métodos , Acuicultura/métodos , Enfermedades de los Peces/etiología , Branquias/patología , Oncorhynchus mykiss , Animales , Vivienda para Animales
4.
Pol J Vet Sci ; 18(4): 793-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26812822

RESUMEN

UNLABELLED: Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in animals, especially in dogs, to manage pain due to inflammatory disease. This study investigated whether plant drugs can prevent mucosal injury induced by robenacoxib. We used fifteen healthy beagle dogs (7 male and 8 female) aged 4 months, weighing 4.2-5.1 kg at the beginning of the study. Endoscopy and biopsy of the colon were performed before and on the 21 day treatment with robenacoxib (1), robenacoxib, herbal solution with liquorice extract (2), placebo - an empty capsule (3). There were 5 animals in each group. The greatest microscopic damage in the colon was observed in animals which received robenacoxib. Plant drug administration reduced the severity of lesions in the colon when administered with robenacoxib (ARI = - 0.15). CONCLUSION: concurrent administration of liquorice extract and plant solution with robenacoxib was associated with significant decreased severity of the robenacoxib-induced colonic mucosal lesions.


Asunto(s)
Enfermedades del Colon/veterinaria , Difenilamina/análogos & derivados , Enfermedades de los Perros/inducido químicamente , Glycyrrhiza/química , Fenilacetatos/efectos adversos , Extractos Vegetales/farmacología , Animales , Antiinflamatorios no Esteroideos/efectos adversos , Enfermedades del Colon/inducido químicamente , Enfermedades del Colon/tratamiento farmacológico , Difenilamina/efectos adversos , Enfermedades de los Perros/tratamiento farmacológico , Perros , Femenino , Mucosa Intestinal/efectos de los fármacos , Masculino , Extractos Vegetales/química
5.
Arch Environ Contam Toxicol ; 64(3): 399-409, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23229198

RESUMEN

The effect of pesticide contamination of the littoral zone on the population of bacteria and fungi was analyzed using the example of a eutrophic water reservoir exposed for >30 years to the influence of expired crop-protection chemicals, mainly DDT. For three consecutive years, quantity analyses of bacteria and fungi were conducted and the composition of the microorganism population analyzed against seasonal dynamics. Mold and yeast-like fungi were also isolated and identified. Within the Bacteria domain, in addition to the large groups of microorganisms (Alphaprotobacteria, Betaprobacteria, and Gammaproteobacteria, Actinobacteria, and Cytophaga-Flavobacterium), the analysis also involved the presence of bacteria predisposed to degraded pesticides in natural environments: Pseudomonas spp. and Alcaligenes spp. The quantity dynamics of aquatic microorganisms indicated that bacteria and fungi under the influence of long-term exposure to DDT can adapt to the presence of this pesticide in water. No modifying effect of DDT was observed on the quantity of microorganisms or the pattern of seasonal relationships in the eutrophic lake. Changes were shown in the percentage share of large groups of bacteria in the community of microorganisms as was an effect of contamination on the species diversity of fungi. The data show the effectiveness of aquatic microorganism-community analyses as a tool for indicating changes in the water environment caused by pesticide contamination.


Asunto(s)
Organismos Acuáticos/efectos de los fármacos , Plaguicidas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Ecosistema , Monitoreo del Ambiente , Eutrofización , Hongos/efectos de los fármacos , Hongos/aislamiento & purificación , Lagos/análisis , Lagos/microbiología , Plaguicidas/análisis , Polonia , Estaciones del Año , Contaminantes Químicos del Agua/análisis
6.
Pol J Vet Sci ; 16(1): 93-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23691581

RESUMEN

Fibromuscular dysplasia (FMD) is a group of nonatherosclerotic, noninflammatory diseases of blood vessels with unknown aetiology. In our study, FMD was diagnosed in blood vessels in samples taken from kidneys, liver and lung of broiler chickens. The FMD occurred during rearing in 8 of 108 broiler chickens examined for the effects of intensive rearing on the.internal organs. Histopathological and immunohistochemical examinations revealed medial subtypes of FMD, medial fibromuscular dysplasia and medial fibromuscular stenosis. The first subtype presented as plugs in vessel lumens consisting of smooth muscle and fibrous connective tissue originating from the tunica media. The second subtype presented as a proliferation of smooth muscle cells and fibroblasts originating from the media and leading to lumen stenosis. The aetiology of FMD is still unknown. Thus, genetic factors are suspected as a cause of the disease. This is the first report of FMD in a vein of an animal species.


Asunto(s)
Pollos , Displasia Fibromuscular/veterinaria , Enfermedades de las Aves de Corral/patología , Venas/patología , Animales , Arterias/citología , Proliferación Celular , Displasia Fibromuscular/patología , Riñón/irrigación sanguínea , Hígado/irrigación sanguínea , Pulmón/irrigación sanguínea
7.
Pol J Vet Sci ; 15(2): 387-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22844719

RESUMEN

The objective of this study was to examine the independent effect of helminths infection on biochemical blood parameters in Beagles intended for laboratory use which may contribute to a change of experimental results. As a result of research, the authors confirmed the negative effect of helminth invasion on the metabolism of the liver and kidney in laboratory dogs. Stool samples from thirty Beagle puppies were examined for parasites before the puppies were moved to the animal facility, and all were dewormed with Vetminth paste on the day they were moved. Stool examination was performed three more times and animals were given Drontal Plus flavor (Bayer) and Baycox 5% (Bayer). A fourth parasitological examination revealed no intestinal parasites in the feces. Three blood biochemical tests were performed. Experimental results clearly indicate the significant impact of intestinal parasites in dogs used in experiments.


Asunto(s)
Enfermedades de los Perros/sangre , Giardiasis/veterinaria , Animales , Coccidiostáticos/uso terapéutico , Enfermedades de los Perros/parasitología , Perros , Giardia lamblia/fisiología , Giardiasis/sangre , Triazinas/uso terapéutico
8.
Hum Exp Toxicol ; 38(1): 11-24, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29766753

RESUMEN

Little is known on the toxicity of nanomaterials in the user phase. Inclusion of nanomaterials in paints is a common nanotechnology application. This study focuses on the toxicity of dusts from sanding of paints containing nanomaterials. We compared the toxicity of titanium dioxide nanomaterials (TiO2NMs) and dusts generated by sanding boards coated with paints with different amounts of two different types of uncoated TiO2NMs (diameters:10.5 nm and 38 nm). Mice were intratracheally instilled with a single dose of 18, 54 and 162 µg of TiO2NMs or 54, 162 and 486 µg of sanding dusts. At 1, 3 and 28 days post-instillation, we evaluated pulmonary inflammation, liver histology and DNA damage in lung and liver. Pulmonary exposure to both pristine TiO2NMs and sanding dusts with different types of TiO2NMs resulted in dose-dependently increased influx of neutrophils into the lung lumen. There was no difference between the sanding dusts from the two paints. For all exposures but not in vehicle controls, mild histological lesions were observed in the liver. Pulmonary exposure to pristine TiO2NMs and paint dusts with TiO2NMs caused similar type of histological lesions in the liver.


Asunto(s)
Polvo , Nanoestructuras/toxicidad , Pintura , Titanio/toxicidad , Animales , Líquido del Lavado Bronquioalveolar/citología , Recuento de Células , Ensayo Cometa , Daño del ADN , Femenino , Hígado/efectos de los fármacos , Hígado/patología , Pulmón/efectos de los fármacos , Pulmón/inmunología , Ratones Endogámicos C57BL , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología
9.
Pol J Vet Sci ; 11(2): 193-7, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18683550

RESUMEN

This paper presents the main trends in the activity of European veterinary pathologists in the context of their oral presentations (plenary lectures and short presentations) and posters provided during annual meetings of the European Society of Veterinary Pathology (ESVP), in the decade 1997-2006. It was found that the issue that was most often brought up in the meetings was organ pathology (566 presentations). Infectious and parasitical diseases were only slightly less frequent (548 presentations). Oncology was another common issue (404 presentations). During this decade, 52 plenary lectures were presented, 765 oral presentations and 1 072 posters. Altogether, 1 889 presentations were made, which is between 127 and 238 per year. Research by Polish scientists accounted for 3.16% of all presentations. Additionally, the subject matter discussed at the annual meetings is analysed, and the trends in the development of veterinary diagnostic pathology and broad pathology education are indicated. It is shown that veterinary pathology enhances knowledge in the field of veterinary medicine by fulfilling a cognitive and diagnostic role.


Asunto(s)
Patología Veterinaria/tendencias , Medicina Veterinaria/tendencias , Animales , Congresos como Asunto , Europa (Continente) , Humanos , Cooperación Internacional , Patología Veterinaria/normas , Polonia , Sociedades , Medicina Veterinaria/normas
10.
J Clin Invest ; 95(5): 2150-60, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7738183

RESUMEN

Cytochrome P450 metabolizes arachidonic acid to several unique and biologically active compounds in rabbit liver and kidney. Microsomal fractions prepared from rabbit lung homogenates metabolized arachidonic acid through cytochrome P450 pathways, yielding cis-epoxyeicosatrienoic acids (EETs) and their hydration products, vic-dihydroxyeicosatrienoic acids, mid-chain cis-trans conjugated dienols, and 19- and 20-hydroxyeicosatetraenoic acids. Inhibition studies using polyclonal antibodies prepared against purified CYP2B4 demonstrated 100% inhibition of arachidonic acid epoxide formation. Purified CYP2B4, reconstituted in the presence of NADPH-cytochrome P450 reductase and cytochrome b5, metabolized arachidonic acid, producing primarily EETs. EETs were detected in lung homogenate using gas chromatography/mass spectroscopy, providing evidence for the in vivo pulmonary cytochrome P450 epoxidation of arachidonic acid. Chiral analysis of these lung EETs demonstrated a preference for the 14(R),15(S)-, 11(S),12(R)-, and 8(S),9(R)-EET enantiomers. Both EETs and vic-dihydroxyeicosatrienoic acids were detected in bronchoalveolar lavage fluid. At micromolar concentrations, methylated 5,6-EET and 8,9-EET significantly relaxed histamine-contracted guinea pig hilar bronchi in vitro. In contrast, 20-hydroxyeicosatetraenoic acid caused contraction to near maximal tension. We conclude that CYP2B4, an abundant rabbit lung cytochrome P450 enzyme, is the primary constitutive pulmonary arachidonic acid epoxygenase and that these locally produced, biologically active eicosanoids may be involved in maintaining homeostasis within the lung.


Asunto(s)
Ácidos Araquidónicos/metabolismo , Hidrocarburo de Aril Hidroxilasas , Sistema Enzimático del Citocromo P-450/metabolismo , Pulmón/enzimología , Microsomas/enzimología , Esteroide Hidroxilasas/metabolismo , Animales , Ácidos Araquidónicos/farmacología , Secuencia de Bases , Northern Blotting , Bronquios/efectos de los fármacos , Bronquios/fisiología , Líquido del Lavado Bronquioalveolar , Cromatografía Líquida de Alta Presión , Sistema Enzimático del Citocromo P-450/biosíntesis , Sistema Enzimático del Citocromo P-450/aislamiento & purificación , Citocromos b5/metabolismo , Expresión Génica , Cobayas , Riñón/enzimología , Cinética , Hígado/enzimología , Masculino , Datos de Secuencia Molecular , Tono Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , NADPH-Ferrihemoproteína Reductasa/metabolismo , Sondas de Oligonucleótidos , Especificidad de Órganos , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Conejos , Esteroide Hidroxilasas/biosíntesis , Esteroide Hidroxilasas/aislamiento & purificación
11.
J Med Chem ; 43(9): 1741-53, 2000 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-10794691

RESUMEN

A set of novel tachykinin-like peptides has been isolated from bullfrog brain and gut. These compounds, ranatachykinin A (RTKA), ranatachykinin B (RTKB), and ranatachykinin C (RTKC), were named for their source, Rana catesbeiana, and their homology to the tachykinin peptide family. We present the first report of the micelle-bound structures and pharmacological actions of the RTKs. Generation of three-dimensional structures of the RTKs in a membrane-model environment using (1)H NMR chemical shift assignments, two-dimensional NMR techniques, and molecular dynamics and simulated annealing procedures allowed for the determination of possible prebinding ligand conformations. RTKA, RTKB, and RTKC were determined to be helical from the midregion to the C-terminus (residues 4-10), with a large degree of flexibility in the N-terminus and minor dynamic fraying at the end of the C-terminus. The pharmacological effects of the RTKs were studied by measuring the elevation of intracellular Ca(2+) in Chinese hamster ovarian cells stably transfected with the bullfrog substance P receptor (bfSPR). All of the RTKs tested elicited Ca(2+) elevations with a rank order of maximal effect of RTKA >/= SP > RTKC >/= RTKB. A high concentration (1 microM) of the neuropeptides produced varying degrees of desensitization to a subsequent challenge with the same or different peptide, while a low concentration (1 pM) produced sensitization at the bfSPR. Our data suggest differences in amino acid side chains and their charged states at the C-terminal sequence or differences in secondary structure at the N-terminus, which do not overlap according to the findings in this paper, may explain the differing degree and type of receptor activation seen at the bfSPR.


Asunto(s)
Receptores de Neuroquinina-1/metabolismo , Taquicininas/metabolismo , Secuencia de Aminoácidos , Animales , Células CHO , Calcio/metabolismo , Canales de Calcio/metabolismo , Cricetinae , Colorantes Fluorescentes , Espectroscopía de Resonancia Magnética , Micelas , Modelos Moleculares , Datos de Secuencia Molecular , Conformación Proteica , Rana catesbeiana , Receptores de Neuroquinina-1/química , Dodecil Sulfato de Sodio
12.
J Appl Physiol (1985) ; 81(1): 260-5, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8828673

RESUMEN

The purpose of this study was to examine the potential functional significance of the sensory nerve inhibitory system in modulating contraction. Tension development in response to electrical field stimulation (EFS) and exogenous acetylcholine was monitored in segments of intrapulmonary bronchi isolated from male Sprague-Dawley rats. Contractile responses to EFS were enhanced by desensitization of sensory nerves with capsaicin, by antagonizing neurokinin NK1 receptors with RP-67580, and by inhibition of cyclooxygenase with meclofenamate. Except for RP-67580, which had a slight inhibitory effect on acetylcholine-induced contractions, these interventions were without effect on contraction to acetylcholine. Incubation of capsaicin-desensitized airway segments with substance P attenuated contractions evoked by a half-maximal frequency of EFS by approximately 92%, whereas contractions elicited by a half-maximal concentration of acetylcholine were not affected. Contractile responses elicited by a lower concentration of acetylcholine were inhibited by approximately 50% by substance P. The inhibitory effect of substance P was blocked by RP-67580, meclofenamate, and epithelial denudation. We conclude that the sensory nerve inhibitory system modulates cholinergic contractions and thus plays a role in the regulation of airway smooth muscle tone.


Asunto(s)
Bronquios/inervación , Neuronas Aferentes/fisiología , Sistema Nervioso Parasimpático/fisiología , Acetilcolina/farmacología , Analgésicos/farmacología , Animales , Bronquios/efectos de los fármacos , Bronquios/fisiología , Capsaicina/farmacología , Inhibidores de la Ciclooxigenasa/farmacología , Estimulación Eléctrica , Epitelio/fisiología , Técnicas In Vitro , Indoles/farmacología , Isoindoles , Masculino , Ácido Meclofenámico/farmacología , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiología , Antagonistas del Receptor de Neuroquinina-1 , Neuronas Aferentes/efectos de los fármacos , Sistema Nervioso Parasimpático/efectos de los fármacos , Prostaglandinas/fisiología , Ratas , Ratas Sprague-Dawley , Sustancia P/farmacología
13.
J Appl Physiol (1985) ; 78(5): 1679-87, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7544339

RESUMEN

We examined the role of sensory nerves in mediating nonadrenergic inhibitory responses in airway segments isolated from male Sprague-Dawley rats. In the presence of adrenergic blockade, capsaicin (Cap; 1 microM) elicited marked relaxation responses in isolated bronchi precontracted with bethanechol (Beth). Cap-induced inhibitory responses were unaffected by tetrodotoxin (TTX), were attenuated by incubation of the airway with indomethacin (Indo), phosphoramidon, or RP-67580, but were abolished by previous exposure of the airway to Cap and by denuding the epithelium. Substance P (SP; 1 microM), neurokinins A and B (1 microM), and calcitonin gene-related peptide (0.1 microM) relaxed Beth-contracted airway segments to a similar extent. The SP-induced responses were unaffected by adrenergic blockade or by pretreatment with either TTX, phosphoramidon, or Cap, but were attenuated by RP-67580 and abolished by Indo and by denuding the epithelium. In anesthetized mechanically ventilated rats, Cap (50 and 100 micrograms/kg i.v.) elicited a dose-dependent reversal of the increase in lung resistance induced by an infusion of Beth. The Cap-induced bronchodilation was unaffected by pretreatment with propranolol alone or in combination with hexamethonium. SP (44 nmol/kg iv) also evoked bronchodilatory responses in intact animals, which were unaffected by propranolol and hexamethonium but were abolished by treatment of the animals with Indo. Electrical-field stimulation (EFS) evoked nonadrenergic noncholinergic relaxation responses in contracted airway segments. These EFS-induced inhibitory responses were markedly attenuated by treatment of the airway segment with TTX, Cap, or RP-67580. We conclude that neuropeptides released from Cap-sensitive sensory nerves have potent inhibitory effects in rat airways that are mediated, in part, by activation of neurokonin NK1 receptors on epithelium and subsequent release of an inhibitory prostaglandin(s).


Asunto(s)
Músculo Liso/fisiología , Neuronas Aferentes/fisiología , Neuropéptidos/fisiología , Tráquea/fisiología , Animales , Betanecol/farmacología , Broncodilatadores/farmacología , Péptido Relacionado con Gen de Calcitonina/metabolismo , Capsaicina/farmacología , Estimulación Eléctrica , Técnicas In Vitro , Masculino , Relajación Muscular/efectos de los fármacos , Relajación Muscular/fisiología , Músculo Liso/efectos de los fármacos , Músculo Liso/metabolismo , Neuroquinina A/metabolismo , Neuronas Aferentes/efectos de los fármacos , Neuronas Aferentes/metabolismo , Neuropéptidos/metabolismo , Ratas , Ratas Sprague-Dawley , Sustancia P/metabolismo , Tetrodotoxina/farmacología , Tráquea/efectos de los fármacos , Tráquea/metabolismo
14.
J Appl Physiol (1985) ; 69(5): 1786-91, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2272972

RESUMEN

SO2 is an environmental pollutant known to elicit bronchospasm in susceptible subjects. We observed that brief exposure of artificially bronchoconstricted cats to high concentrations of SO2 induces a bronchodilator response. This study assessed the characteristics of this response and examined various mechanisms that might underlie it. Cats were anesthetized with diallylbarbital-urethan, and airway smooth muscle tone, measured by lung resistance and dynamic lung compliance, was elevated with a continuous infusion of 5-hydroxytryptamine. Administration of 10 breaths of SO2 via a tracheostomy induced concentration-dependent bronchodilation in the range 100-1,000 parts/million. Only infrequently was bronchoconstriction observed before bronchodilation. SO2-induced bronchodilator responses were unaffected by pretreatment with intravenous atropine or propranolol, establishing them as nonadrenergic noncholinergic (NANC) in origin. Neither the ganglionic blocking agent hexamethonium nor the nerve toxin tetrodotoxin influenced the SO2-induced bronchodilation, thus excluding a role for central or local autonomic reflexes in the response. Efforts to modulate the response by pretreatment with the cyclooxygenase inhibitor indomethacin or the mediator release inhibitor cromolyn sodium also were unsuccessful. Administration of acidic aerosols failed to mimic the SO2-induced bronchodilator response. Although the mechanism whereby SO2 induces bronchodilation under these experimental conditions remains unclear, release of a NANC inhibitory transmitter from a neural, epithelial, or other cellular source via a mechanism insensitive to both tetrodotoxin and cromolyn is a distinct possibility. An intrinsic NANC inhibitory system may exist in feline airways functioning as a local regulator of bronchomotor tone and possibly serving to override responses to strong, potentially asphyxial bronchoconstrictive stimuli.


Asunto(s)
Broncodilatadores/farmacología , Dióxido de Azufre/farmacología , Animales , Broncoconstricción/efectos de los fármacos , Gatos , Relación Dosis-Respuesta a Droga , Femenino , Rendimiento Pulmonar , Masculino , Concentración Osmolar , Dióxido de Azufre/antagonistas & inhibidores
15.
J Appl Physiol (1985) ; 65(5): 2326-31, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3145283

RESUMEN

Pulmonary hypertension in rats, induced by an injection of monocrotaline, is associated with changes in the wall structure of the pulmonary arterial bed. We have studied the effects of this remodeling on mechanical properties of cylindrical pulmonary artery segments from rats 21 days after monocrotaline (MCT) injection. Resting and active (KCl induced) circumference-tension relationships were established for segments of extrapulmonary and intrapulmonary arteries isolated from the hilum and the fifth lateral branch from the axial pathway (all preacinar). The thicknesses of the vessel wall, the media, and adventitia were measured at several positions around the circumference of the artery by computerized analysis of histological cross sections of the segments fixed at a standard circumference. Resting and active stress were also calculated. The study shows that active circumferential tension and active stress are reduced in vessels from MCT-treated rats. Based on our findings, it is unlikely that altered contractile function of preacinar arteries contributes significantly to the increased vascular resistance seen in this model.


Asunto(s)
Hipertensión Pulmonar/fisiopatología , Arteria Pulmonar/efectos de los fármacos , Alcaloides de Pirrolicidina/toxicidad , Animales , Fenómenos Biomecánicos , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/patología , Técnicas In Vitro , Masculino , Monocrotalina , Contracción Muscular/efectos de los fármacos , Arteria Pulmonar/patología , Arteria Pulmonar/fisiopatología , Ratas , Ratas Endogámicas , Resistencia Vascular/efectos de los fármacos
16.
Peptides ; 3(1): 27-9, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6176975

RESUMEN

The ability of substance P to mimic vagally mediated nonadrenergic bronchodilation was assessed in vivo in anesthetized, paralyzed, artificially ventilated cats. Infusion of the peptide at a rate of 10 micrograms kg-1 min-1 for 10 minutes did not attenuate the increase in pulmonary resistance evoked by efferent vagal stimulation. Similarly, when administered as an aerosol (1-15 breaths of a 100 micrograms ml-1 aqueous solution) or by bolus intravenous injection, substance P failed to reverse the increase in pulmonary resistance maintained by a continuous intravenous infusion of 5-hydroxytryptamine. These results indicate that substance P is unlikely to be the neurotransmitter responsible for mediating nonadrenergic inhibitory responses in feline airways.


Asunto(s)
Bronquios/efectos de los fármacos , Contracción Muscular/efectos de los fármacos , Relajación Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Sustancia P/farmacología , Nervio Vago/fisiología , Animales , Gatos , Estimulación Eléctrica , Femenino , Masculino , Serotonina/farmacología , Péptido Intestinal Vasoactivo/farmacología
17.
Eur J Pharmacol ; 231(3): 339-46, 1993 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-8449226

RESUMEN

5-Hydroxytryptamine (5-HT) potentiated contractions of isolated rat bronchi evoked by electrical field stimulation (EFS). The degree of potentiation caused by 5-HT was dependent upon concentration of the amine present in the tissue bath. The effects of antagonists selective for different subtypes of the 5-HT receptor on potentiation of EFS-induced contractions by 5-HT were examined. Propranolol, a nonselective beta-adrenoceptor antagonist which can act as a 5-HT1 receptor antagonist, did not inhibit the effect of 5-HT on EFS-induced contractile responses. Similarly, 5-HT3 receptor antagonism with MDL 72222 or ICS 205-930, did not inhibit the facilitatory effects of 5-HT. However, ketanserin, mianserin and spiperone, 5-HT2 receptor antagonists, abolished the effects of 5-HT on EFS-induced responses. These latter results suggested that the potentiation was dependent upon activation of 5-HT2 receptors thus additional experiments were conducted using the 5-HT2 receptor agonist, alpha-methyl-5-hydroxytryptamine (alpha-Me-5-HT). alpha-Me-5-HT caused a concentration-dependent potentiation of EFS-induced contractile responses comparable to that observed with 5-HT. Concentrations of alpha-Me-5-HT that significantly potentiated EFS-induced contraction were essentially without effect on airway smooth muscle contraction elicited by exogenous acetylcholine. These results are consistent with a role for 5-HT2 receptor activation in mediating the facilitatory effects of 5-HT on cholinergic nerve-mediated responses in airways.


Asunto(s)
Broncoconstricción/efectos de los fármacos , Receptores de Serotonina/efectos de los fármacos , Antagonistas de la Serotonina/farmacología , Serotonina/farmacología , Animales , Sinergismo Farmacológico , Estimulación Eléctrica , Masculino , Ratas , Ratas Sprague-Dawley
18.
Eur J Pharmacol ; 257(3): 275-83, 1994 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-7522173

RESUMEN

This study was initiated to test the hypothesis that histamine can act as an endothelium-derived contracting factor in bovine isolated intrapulmonary vein. The effects of calcium ionophore, calcimycin (A23187), on isometric tension were compared in unstimulated rings of intrapulmonary vein with and without endothelium. A23187 (0.1-10 microM) induced concentration-related contraction when endothelium was present. Destruction of endothelium markedly inhibited A23187-induced contraction. Methylene blue, hemoglobin or NG-methyl-L-arginine significantly enhanced A23187-induced contraction only in venous rings with endothelium consistent with attenuation of the contraction by the concomitant release of endothelium-derived relaxing factor (nitric oxide) [EDRF(NO)]. Histamine H1 receptor antagonists inhibited, and iproniazid enhanced, contraction elicited by A23187. A23187 induced release of greater amounts of histamine from venous rings with than without endothelium. A23187-induced contraction was not mimicked by the mast cell activator, compound 48/80, and was not inhibited by preexposure to compound 48/80 or in the presence of cromolyn or doxantrazole. A23187-induced contraction was not inhibited by pretreatment with indomethacin, phentolamine, lipoxygenase inhibitors or superoxide dismutase. The results indicate that A23187 induces endothelium-dependent contraction in bovine intrapulmonary vein and support histamine as one major mediator involved. The association of destruction of endothelium with an inhibition of both A23187-induced contraction and histamine release is consistent with the endothelium as a source for histamine which can exert a local vasoconstrictor effect in bovine intrapulmonary vein.


Asunto(s)
Calcimicina/farmacología , Endotelio Vascular/fisiología , Histamina/fisiología , Músculo Liso Vascular/efectos de los fármacos , Venas Pulmonares/efectos de los fármacos , Animales , Arginina/análogos & derivados , Arginina/farmacología , Atropina/farmacología , Bovinos , Cromolin Sódico/farmacología , Endotelinas/farmacología , Hemoglobinas/farmacología , Antagonistas de los Receptores Histamínicos H1/farmacología , Liberación de Histamina/efectos de los fármacos , Técnicas In Vitro , Iproniazida/farmacología , Azul de Metileno/farmacología , Contracción Muscular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Tioxantenos/farmacología , Xantonas , omega-N-Metilarginina , p-Metoxi-N-metilfenetilamina/farmacología
19.
Eur J Pharmacol ; 217(2-3): 109-18, 1992 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-1358631

RESUMEN

This study examined the effects of chlorpheniramine, citalopram and fluoxetine on 5-hydroxytryptamine (5-HT)-induced contraction and 5-HT uptake in rat thoracic aortic rings in vitro. Chlorpheniramine and citalopram markedly potentiated 5-HT-induced contraction. Potentiation by fluoxetine was less pronounced. Chlorpheniramine (0.01-1 microM) and citalopram (0.1-1 microM) induced concentration-dependent parallel shifts to the left of the 5-HT concentration-response curves. The potentiation by chlorpheniramine was selective as chlorpheniramine (1 microM) did not potentiate phenylephrine-induced contraction. The potentiation did not depend upon the presence of endothelium, and was not related to H1 receptor antagonism as diphenhydramine and pyrilamine (1 microM) did not similarly enhance 5-HT-induced contractions. Whereas cocaine (1-10 microM) similarly potentiated 5-HT-induced contraction, imipramine (1-10 microM) inhibited, rather than enhanced, contraction elicited by 5-HT. In the presence of 10 microM cocaine, maximally effective concentrations of chlorpheniramine (1 microM) or citalopram (100 nM) did not induce any additional potentiation of 5-HT-induced contraction. Cooling (4 degrees C) markedly inhibited uptake of [3H]5-HT in rings with and without endothelium. Although less marked, imipramine (10 microM), cocaine (1 microM), chlorpheniramine (1 microM) and citalopram (100 nM) inhibited [3H]5-HT uptake in endothelium-intact and endothelium-denuded rings. Fluoxetine also inhibited [3H]5-HT uptake, but the inhibition was only statistically significant in endothelium-intact rings. The monoamine oxidase (MAO) inhibitor, pargyline (10-100 microM), did not significantly affect 5-HT-induced contraction. The results demonstrate that chlorpheniramine, citalopram and to a lesser extent, fluoxetine potentiate 5-HT-induced contraction in rat aorta in which neuronal 5-HT uptake is negligible. The data are consistent with inhibition of non-neuronal 5-HT uptake as at least one mechanism responsible for potentiation of 5-HT-induced contraction in rat aorta by chlorpheniramine, citalopram and fluoxetine.


Asunto(s)
Clorfeniramina/farmacología , Citalopram/farmacología , Fluoxetina/farmacología , Serotonina/farmacología , Vasoconstricción/efectos de los fármacos , Animales , Aorta Torácica/efectos de los fármacos , Cocaína/farmacología , Relación Dosis-Respuesta a Droga , Antagonistas de los Receptores Histamínicos H1/farmacología , Imipramina/farmacología , Técnicas In Vitro , Masculino , Pargilina/farmacología , Ratas , Ratas Sprague-Dawley
20.
Acad Med ; 76(4 Suppl): S72-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11299174

RESUMEN

Meeting the objectives and requirements of the Interdisciplinary Generalist Curriculum (IGC) Project had positive and negative effects on the university-based basic science and clinical faculty, which have been divided into four categories: boundary issues, collaboration, teaching, and development. The specific experiences of two schools, the University of California, San Francisco, School of Medicine and the Joan C. Edwards School of Medicine at Marshall University, are compared against the experiences of the ten schools as documented in the IGC Project external evaluation team's final report. Boundary issues regarded as negative effects of the IGC Project included perceived encroachment on the time devoted to basic science education, loss of the unique identity of the university-based faculty as academicians, and reduced prominence of subspecialist clinical faculty. Effects of the IGC Project in the other areas were, for the most part, positive. The increased collaboration yielded a net benefit to the university-based faculty at large. The clinical faculty experienced more opportunities to teach. Introduction of teacher development programs were of benefit to both clinical and basic science faculty. The other arm of development, professional development, was evidenced by increased stature and promotions of IGC faculty directors. In conclusion, changes within the university-based faculty occurred in stages as faculty realized that the design of the IGC Project enhanced the educational experience of the students.


Asunto(s)
Educación de Pregrado en Medicina , Docentes Médicos , Conducta Cooperativa , Curriculum , Humanos , Relaciones Interprofesionales , Modelos Educacionales , Preceptoría , Evaluación de Programas y Proyectos de Salud , Enseñanza , Estados Unidos
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