RESUMEN
Adrenergic receptors are mediators of adrenergic and noradrenergic modulation throughout the brain. Previous studies have provided evidence for the expression of adrenergic receptors in the midbrain auditory nucleus, the inferior colliculus (IC), but have not examined the cellular patterns of expression in detail. Here, we utilize multichannel fluorescent in situ hybridization to detect the expression of adrenergic receptor-encoding mRNA in the inferior colliculus of male and female mice. We found expression of α1 , α2A , and ß2 receptor-encoding mRNA throughout all areas of the IC. While we observed similar levels of expression of α1 receptor-encoding mRNA across the subregions of the IC, α2A and ß2 receptor-encoding mRNA was expressed differentially. To account for developmental changes in noradrenergic receptor expression, we measured expression levels in mice aged P15, P20, and P60. We observed little change in levels of expression across these ages. To ascertain the modulatory potential of multiple adrenergic receptor subtypes in a single IC cell, we measured co-expression of α1 , α2A , and ß2 receptor-encoding mRNA. We found greater proportions of cells in the IC that expressed no adrenergic receptor-encoding mRNA, α1 and α2A adrenergic receptor-encoding mRNA, and α1, α2A, and ß2 receptor-encoding mRNA than would be predicted by independent expression of each receptor subtype. These data suggest a coordinated pattern of adrenergic receptor expression in the IC and provide the first evidence for adrenergic receptor expression and co-expression in the subregions of the mouse auditory midbrain.
Asunto(s)
Colículos Inferiores/metabolismo , ARN Mensajero/análisis , Receptores Adrenérgicos/metabolismo , Animales , Femenino , Masculino , Ratones , Receptores Adrenérgicos/análisisRESUMEN
UNLABELLED: This review is based on the JR Vane Medal Lecture presented at the BPS Winter Meeting in December 2011 by J.C. McGrath. A recording of the lecture is included as supporting information. It covers his laboratory's work from 1990 to 2010 on the localization of vascular α1 -adrenoceptors in native tissues, mainly arteries. MAIN POINTS: (i) α1 -adrenoceptors are present on several cell types in arteries, not only on medial smooth muscle, but also on adventitial, endothelial and nerve cells; (ii) all three receptor subtypes (α1 A , α1 B , α1 D ) are capable of binding ligands at the cell surface, strongly indicating that they are capable of function and not merely expressed. (iii) all of these cell types can take up an antagonist ligand into the intracellular compartments to which endocytosing receptors move; (iv) each individual subtype can exist at the cell surface and intracellularly in the absence of the other subtypes. As functional pharmacological experiments show variations in the involvement of the different subtypes in contractions of different arteries, it is concluded that the presence and disposition of α1 -adrenoceptors in arteries is not a simple guide to their involvement in function. Similar locations of the subtypes, even in different cell types, suggest that differences between the distribution of subtypes in model systems do not directly correlate with those in native tissues. This review includes a historical summary of the alternative terms used for adrenoceptors (adrenergic receptors, adrenoreceptors) and the author's views on the use of colours to illustrate different items, given his partial colour-blindness.
Asunto(s)
Arterias/química , Arterias/metabolismo , Receptores Adrenérgicos/análisis , Receptores Adrenérgicos/metabolismo , Animales , Arterias/citología , Humanos , LigandosRESUMEN
Excitatory responses evoked by N-methyl-d-aspartate (NMDA) in the vestibular nuclei (VN) of the rat were studied in vivo during microiontophoretic application of noradrenaline (NA) and/or its agonists and antagonists. Ejection of NA-modified excitatory responses mediated by NMDA receptors (NMDAR) in all neurons tested; the effect was enhancement in 59% of cases and depression in the remaining 41%. Enhancements prevailed in all VN with the exception of the lateral vestibular nucleus, where both effects were recorded in an equal number of cases. The enhancing action of NA on NMDAR-mediated responses was mimicked by the noradrenergic beta-receptor agonist isoproterenol, the beta1 specific agonist denopamine and the alpha2 agonist clonidine. These effects were blocked respectively by the generic beta-receptor antagonist timolol, the beta1 antagonist atenolol and the alpha2 antagonist yohimbine. In contrast, application of the alpha1 receptor agonist cirazoline and the specific alpha1 antagonist prazosin respectively mimicked and partially antagonized the depression of NMDAR-mediated excitations induced by NA. Double-labeling immunohistochemical techniques demonstrated broad colocalization of NMDAR (specifically NR1 and NR2 subunits) with noradrenergic receptors (alpha1, alpha2 and beta1) in many VN neurons; only minor differences were found between nuclei. These results indicate that NA can produce generalized modulation of NMDAR-mediated excitatory neurotransmission in VN, which may in turn modify synaptic plasticity within the nuclei.
Asunto(s)
Neuronas/fisiología , Norepinefrina/farmacología , Receptores de N-Metil-D-Aspartato/metabolismo , Núcleos Vestibulares/metabolismo , Animales , Fenómenos Electrofisiológicos , Inmunohistoquímica , Masculino , N-Metilaspartato/farmacología , Neuronas/efectos de los fármacos , Norepinefrina/agonistas , Norepinefrina/antagonistas & inhibidores , Ratas , Ratas Wistar , Receptores Adrenérgicos/análisis , Receptores Adrenérgicos/metabolismo , Receptores de N-Metil-D-Aspartato/análisis , Núcleos Vestibulares/efectos de los fármacosRESUMEN
Downregulation of ß(1)- adrenergic receptors (ß(1)-ARs) and increased expression/function of G-protein-coupled receptor kinase 2 (GRK2) have been observed in human heart failure, but changes in expression of other ARs and GRKs have not been established. Another unresolved question is the incidence of these compensatory mechanisms depending on heart failure etiology and treatment. To analyze these questions, we quantified the mRNA/protein expressions of six ARs (α(1A), α(1B), α(1D), ß(1), ß(2), and ß(3)) and three GRKs (GRK2, GRK3, and GRK5) in left (LV) and right ventricle (RV) from four donors, 10 patients with ischemic cardiomyopathy (IC), 14 patients with dilated cardiomyopathy (DC), and 10 patients with nonischemic, nondilated cardiopathies (NINDC). We correlated the changes in the expressions of ARs and GRKs with clinical variables such as left ventricular ejection fraction (LVEF) and left ventricular end-systolic and left ventricular end-diastolic diameter (LVESD and LVEDD, respectively). The main findings were 1) the expression of the α(1A)-AR in the LV positively correlates with LVEF; 2) the expression of GRK3 and GRK5 inversely correlates with LVESD and LVEDD, supporting previous observations about a protective role for both kinases in failing hearts; and 3) ß(1)-AR expression is downregulated in the LV and RV of IC, in the LV of DC, and in the RV of NINDC. This difference, better than an increased expression of GRK2 (not observed in IC), determines the lower LVEF in IC and DC vs. NINDC.
Asunto(s)
Cardiomiopatías/etiología , Cardiomiopatías/metabolismo , Quinasas de Receptores Acoplados a Proteína-G/genética , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/metabolismo , Isquemia Miocárdica/complicaciones , Miocardio/química , Receptores Adrenérgicos/análisis , Adulto , Análisis de Varianza , Cardiomiopatías/tratamiento farmacológico , Cardiomiopatías/genética , Cardiomiopatías/fisiopatología , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/etiología , Cardiomiopatía Dilatada/genética , Cardiomiopatía Dilatada/metabolismo , Cardiomiopatía Dilatada/fisiopatología , Femenino , Genotipo , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/fisiopatología , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/fisiopatología , Fenotipo , ARN Mensajero/análisis , Receptores Adrenérgicos/genética , España , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
Alterations in cardiac function were observed in antidepressants treated patients and published in several clinical reports. These detected changes could be either a consequence of the treatment or of depression itself, which has already been proved to be a risk factor in heart diseases. In order to determine a possible influence of chronic treatment with norepinephrinergic reuptake inhibitor, maprotiline, on the heart, we investigated gene expression of cardiac β-adrenoceptors both in controls and in animals with signs of depression. The rats were divided into two groups, unstressed controls and those exposed to chronic unpredictable mild stress (CUMS). The groups were further divided into two subgroups, one receiving daily intraperitoneal injections of vehicle (sterile water) and another one maprotiline (10 mg/kg) for four weeks. Tissue samples were collected after the last application. Gene expression of cardiac β1- and β2-adrenoceptor was determined using Real-time RT-PCR analysis. Our results show that in control animals expression of both adrenoreceptors was decreased in the right atria after 4 weeks of maprotiline application. Contrary, the same treatment led to a significant increase in expression of cardiac β1-adrenoceptor in the stressed rats, with no change in the characteristics of β2-adrenoceptor. Our findings might reflect the that molecular mechanisms are underlying factors involved in the development of cardiovascular diseases linked with antidepressant treatment.
Vários relatórios clínicos observaram alterações de funcionamento cardíaco de pacientes depressivos que foram tratados com os antidepressivos. As alterações detectadas podem ser consequência do tratamento ou, por outro lado, da depressão que, como se tem provado, é um fator de risco no caso de doenças cardíacas. De modo a determinar a possível influência de tratamento crônico com o inibidor da recaptação de norepinefrina, maprotilina, no coração, foi investigada a expressão do gene aos receptores β-adrenérgicos cardíacos dos animais em grupos de controle e em grupos com sinais de depressão. Os ratos foram divididos em grupos de controle não estressados e os grupos de ratos submetidos ao estresse crônico moderado imprevisível (CUMS). Os grupos foram, ainda, divididos em dois subgrupos, que, durante quatro semanas, diariamente receberam injeções intraperitoneais de placebo (água estéril) ou de maprotilina (10 mg/kg). As amostras de tecido foram coletadas após a última aplicação. A expressão do gene aos receptores adrenérgicos β1 e β2 foi determinada utilizando a análise PCR quantitativa em tempo real (RT-PCR). Os nossos resultados demonstram a diminuição de expressão dos ambos os receptores adrenérgicos no átrio direito dos animais do grupo de controle depois de quatro semanas de aplicação de maprotilina. Em contraste, o mesmo tratamento conduziu ao aumento significativo na expressão do receptor β1-adrenérgico no coração dos ratos estressados, sem qualquer alteração nas características do receptor β2-adrenérgico. Estes resultados podem refletir os mecanismos moleculares envolvidos no desenvolvimento de doenças cardiovasculares associadas ao tratamento com os antidepressivos.
Asunto(s)
Ratas , Receptores Adrenérgicos/análisis , Maprotilina , Antidepresivos/clasificación , Enfermedades Cardiovasculares/clasificación , Expresión Génica , DepresiónRESUMEN
BACKGROUND: Nowadays translational medicine is acquiring a more and more important role in connecting laboratory experimental results on human tissues to clinical findings and drug employment. We want to underline the importance of in vitro studies, which have been extensively performed on animal organs, but few studies have been performed on human tissues. Nevertheless, a more accurate result when compared to the in vivo use of drugs can be given only by testing the very same human tissues in a lab. We related clinical treatments of different pathologies with the results obtained in laboratory studying in vitro fragments of human organs extracted during surgery exposed to different mediators and drugs. METHODS: Fragments of urethers, bladder (detrusorial muscle and bladder neck muscle fibers), corpora cavernosa, and vas deferens were extracted during demolitive surgery trying not to traumatize the tissue, in order to keep it alive and not to ruin its contractile fibers. The fragments were then put into polisaline solution and, once in the laboratory, fixed on suitable isolated organ support, fixed at one side of the thermostatic pool and on the other side connected to a digital monitoring system. The contractility was then studied after adding different mediators. RESULTS: The urethers have shown a stronger response to NE and PGF2a, with a different contractility in their distal part due to a major concentration of alpha-receptors; the bladder neck has also shown a strong contractile response to NE and PGF2a, and is inhibited by alpha-blockers; the bladder detrusor, instead, responds to ACH (acetylcholine) and PGF2a; the vas deferens shows a different type of contractility in the prostatic part compared to the epididimary part when stimulated with noradrenaline and PGF2a; the corpora cavernosa respond to NE and PGF2a. CONCLUSIONS: The results obtained after stimulating the fragments can explain and prove the receptorial activity of inner mediators and of commonly used drugs which have, for years, been used empirically; the simplicity and repetitivity of the method can be considered and used not only to research the physiological functioning of different organs, but also the functioning of new drugs before testing them on patients, being more reliable and accurate than tests on animal tissues. This experimental work has shown that using human tissues in testing specific mediators is the most reliable laboratory method.
Asunto(s)
Receptores Adrenérgicos/análisis , Investigación Biomédica Traslacional , Uréter/química , Vejiga Urinaria/química , Conducto Deferente/química , Humanos , Técnicas In Vitro , MasculinoRESUMEN
Commercially available antisera against five subtypes of muscarinic receptors and nine subtypes of adrenoceptors showed highly distinct immunohistochemical staining patterns in rat ureter and stomach. However, using the M(1-4) muscarinic receptor subtypes and alpha(2B)-, beta(2)-, and beta(3)-adrenoceptors as examples, Western blots with membranes prepared from cell lines stably expressing various subtypes of muscarinic receptors or adrenoceptors revealed that each of the antisera recognized a set of proteins that differed between the cell lines used but lacked specificity for the claimed target receptor. We propose that receptor antibodies need better validation before they can reliably be used.
Asunto(s)
Especificidad de Anticuerpos/inmunología , Sueros Inmunes/inmunología , Receptores Adrenérgicos/análisis , Receptores Adrenérgicos/inmunología , Receptores Muscarínicos/análisis , Receptores Muscarínicos/inmunología , Animales , Anticuerpos/inmunología , Western Blotting , Química Encefálica , Línea Celular , Tracto Gastrointestinal/química , Humanos , Inmunohistoquímica , Ratas , Ratas Wistar , Receptores Adrenérgicos/genética , Receptores Muscarínicos/genética , Transfección , Sistema Urinario/químicaRESUMEN
The intrinsic structural determinants for export trafficking of G protein-coupled receptors (GPCRs) have been mainly identified in the termini of the receptors. In this report, we determined the role of the first intracellular loop (ICL1) in the transport from the endoplasmic reticulum (ER) to the cell surface of GPCRs. The alpha(2B)-adrenergic receptor (AR) mutant lacking the ICL1 is unable to traffic to the cell surface and to initiate signaling measured as ERK1/2 activation. Mutagenesis studies identify a single Leu48 residue in the ICL1 modulates alpha(2B)-AR export from the ER. The ER export function of the Leu48 residue can be substituted by Phe, but not Ile, Val, Tyr and Trp, and is unlikely involved in correct folding or dimerization of alpha(2B)-AR in the ER. Importantly, the isolated Leu residue is remarkably conserved in the center of the ICL1s among the family A GPCRs and is also required for the export to the cell surface of beta(2)-AR, alpha(1B)-AR and angiotensin II type 1 receptor. These data indicate a crucial role for a single Leu residue within the ICL1 in ER export of GPCRs.
Asunto(s)
Retículo Endoplásmico/metabolismo , Leucina/análisis , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Animales , Transporte Biológico , Membrana Celular/metabolismo , Citoplasma/metabolismo , Dimerización , Retículo Endoplásmico/química , Isoleucina/análisis , Isoleucina/metabolismo , Leucina/metabolismo , Fenilalanina/análisis , Fenilalanina/metabolismo , Transporte de Proteínas/fisiología , Receptor de Angiotensina Tipo 1/análisis , Receptor de Angiotensina Tipo 1/metabolismo , Receptores Adrenérgicos/análisis , Receptores Adrenérgicos/metabolismo , Receptores Acoplados a Proteínas G/análisis , Transducción de SeñalRESUMEN
BACKGROUND: Human apocrine (epitrichial) sweat glands secrete in response to local or systemic administration of catecholamines and cholinergic agonists. As the process of secretion in human apocrine glands is not fully understood and no literature detailing the expression of adrenergic, cholinergic and purinergic receptors is available, there is a need to know the receptor types. Such data could provide new approaches for the treatment of axillary bromhidrosis. OBJECTIVES: To investigate the localization of nerve fibres, adrenergic, cholinergic and purinergic receptors in human axillary apocrine sweat glands by immunohistochemistry. METHODS: Human axillary apocrine sweat glands were investigated by serial sectioning of paraffin wax-embedded skin samples from volunteers. Sections were examined by light microscopy and immunohistochemistry, using antibodies against neurofilament, alpha- and beta-adrenoceptors, P2Y(1), P2Y(2) and P2Y(4) purinoceptors, and M(3) cholinoceptors. RESULTS: Neurofilaments were found near the eccrine but not the apocrine gland. Apocrine glands demonstrated the presence of beta-2 and beta-3 adrenoceptors in the secretory coil of the gland, but not alpha-1, beta-1 or M(3) receptors. Glandular purinergic staining (P2Y(1), P2Y(2) and P2Y(4)) was found in what looked like myoepithelial cells, while P2Y(1) and P2Y(2) staining was found on apical membranes and diffusely throughout secretory cells. Eccrine gland staining acted as internal positive controls. CONCLUSIONS: No nerve fibres were found near the apocrine gland, suggesting that any catecholamine influence is through humoral effects and that glands could be influenced by beta-adrenoceptor subtypes and purinoceptors. Blockage of both these types of receptors offers a route to controlling apocrine secretion from axillary glands and reducing the opportunity for the development of bromhidrosis.
Asunto(s)
Glándulas Apocrinas/inervación , Glándulas Apocrinas/metabolismo , Proteínas de Neurofilamentos/análisis , Receptor Muscarínico M3/análisis , Receptores Adrenérgicos/análisis , Receptores Purinérgicos/análisis , Adulto , Axila , Biomarcadores/análisis , Femenino , Humanos , Hiperhidrosis/tratamiento farmacológico , Hiperhidrosis/metabolismo , Hiperhidrosis/fisiopatología , Inmunohistoquímica , Masculino , Receptores Adrenérgicos alfa 1/análisis , Receptores Adrenérgicos beta 1/análisis , Receptores Adrenérgicos beta 2/análisis , Receptores Adrenérgicos beta 3/análisis , Receptores Purinérgicos P2/análisis , Receptores Purinérgicos P2Y1 , Receptores Purinérgicos P2Y2 , Coloración y EtiquetadoRESUMEN
Although the tricyclic antidepressants, such as desipramine (DMI), are among the most efficacious treatments for adult depression, they are not effective in treating childhood and adolescent depression. Because the adrenergic nervous system is not fully developed until late adolescence, we hypothesized that the mechanisms regulating receptor density may not yet be mature in young mammals. To test this hypothesis, the effects of DMI treatment on cortical alpha-1-, alpha-2-, and beta-adrenergic receptors were compared in juvenile and adult rats. DMI was delivered either by 4 days of twice daily injections to postnatal day 9 to 13 (4 and 7 mg/kg/day) and adult (20 mg/kg/day) rats, or by 2 weeks of continual drug infusion (osmotic minipumps) to postnatal day 21-35 (15 mg/kg/day) and adult (10 mg/kg/day) rats. These delivery paradigms gave juvenile brain concentrations of DMI similar to those in adult rats. The beta-adrenergic receptor was down-regulated with both treatment paradigms in both juvenile and adult rats. By contrast, in the postnatal day 9 to 13 rats, there was a dose-dependent up-regulation of the alpha-1 in the cortex and alpha-2-adrenergic receptor in the prefrontal cortex, whereas there was no change in density in adult rats. These differences in the alpha-adrenergic receptor regulation after DMI treatment suggest that the lack of efficacy of tricyclic antidepressants in treating childhood depression may be related to immature regulatory mechanisms for these receptors.
Asunto(s)
Antidepresivos Tricíclicos/farmacología , Desipramina/farmacología , Receptores Adrenérgicos/efectos de los fármacos , Factores de Edad , Animales , Corteza Cerebral/química , Masculino , Corteza Prefrontal/química , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos/análisis , Receptores Adrenérgicos alfa 1/análisis , Receptores Adrenérgicos alfa 2/análisisRESUMEN
The ligand-binding characteristics (B(max) and K(D)) of alpha(1)- and beta(1)/beta(2)-adrenoceptors were investigated in membranes prepared from brown adipose tissue (BAT) of warm-acclimated, cold-acclimated, hibernating and arousing ground squirrels (Spermophillus undulatus) and hamsters (Mesocricetus auratus) by specific binding of [(3)H]prazosin and [(3)H]CGP-12177, respectively. The physiological state did not change the affinity for the adrenoceptors in the BAT of ground squirrels and hamsters. There was a significant decrease in alpha(1)-receptor density in arousing ground squirrels and a significant decrease in beta(1)/beta(2) density in hibernating ground squirrels. The level of alpha(1)-receptors was in all conditions higher than that of beta(1)/beta(2) receptors. The results indicate a possible change in balance of adrenoceptor density in the processes of cold acclimation, hibernation and arousal. The balance between the various adrenoceptor subtypes may be important for the final effect of catecholamines in BAT in different physiological states.
Asunto(s)
Tejido Adiposo Pardo/química , Hibernación/fisiología , Mesocricetus/fisiología , Receptores Adrenérgicos/análisis , Sciuridae/fisiología , Aclimatación , Tejido Adiposo Pardo/fisiología , Animales , Nivel de Alerta/fisiología , Frío , Cricetinae , Femenino , Masculino , Prazosina/metabolismo , Propanolaminas/metabolismo , Receptores Adrenérgicos alfa 1/análisis , Receptores Adrenérgicos beta 1/análisis , Receptores Adrenérgicos beta 2/análisisRESUMEN
Sjögren's syndrome is an autoimmune disorder characterized by a progressive, immune-mediated destruction of mucosal tissues such as the lacrimal and salivary glands, leading to ocular and oral dryness. The MRL/MpJ-Fas(lpr) mouse is one of the animal models used to study this disease. However, little is known about the potential alterations in the conjunctiva in this murine model. The purpose of this study was to determine: (1) whether the conjunctiva is infiltrated by T lymphocytes, (2) characterize the type, amount and temporal sequence of the inflammatory infiltrates, and (3) investigate whether the amount of conjunctival goblet cells is altered in this murine model of Sjögren's syndrome. Female 4-, 9-, 13-, 16-, and 18-/20-wk-old MRL/MpJ-Fas(lpr) (lpr, diseased) and congenic MRL/MpJ (+/+, control) mice were used. Right eyes were either fixed, frozen, cryosectioned, and studied by immunofluorescence microscopy or the conjunctiva was removed, homogenized and analyzed by electrophoresis and Western blot analysis. The following antibodies were used: anti-CD3 (specific T lymphocyte marker), anti-cytokeratin 7 (CK-7), anti-PKD (formerly known as PKCmu, both markers of goblet cell bodies), anti-PGP 9.5 (pan-neuronal marker), anti-VIP and TH (markers for parasympathetic and sympathetic nerves, respectively), anti-adrenergic (alpha(1) and beta(1-3)) and muscarinic (M(1)-M(3)) receptor subtypes (markers for neurotransmitter receptors of the sympathetic and parasympathetic pathways, respectively). Left eyes were fixed, embedded, sectioned, and stained. Hematoxylin/eosin, Giemsa, or alcian blue/periodic acid Schiff's reagent were used to study lymphocyte infiltration; to determine the presence of eosinophils, neutrophils, and mast cells; and to count the number of goblet cells, respectively. By immunofluorescence microscopy, lymphocytes were detected in the conjunctiva of 9-wk-old lpr, but not +/+, mice. The lymphocytic infiltration became more extensive as the animals aged, with 16- and 18-/20-wk lpr mice appearing to have a greater lymphocytic infiltration than +/+ mice at the same age. By Western blot analysis, the amount of CD3 was enhanced in lpr compared to +/+ mice by the 16th wk, but not by the 9th wk. No major differences in the presence of eosinophils, neutrophils and degranulated mast cells between lpr and +/+ mice were observed. By light microscopy, a significant increase in goblet cell number was found in lpr mice compared to +/+ mice at 16 wks on. By Western blotting, the amount of CK-7 was significantly increased at 9 wks on and the amount of PKD was significantly increased at 16 wks. By immunofluorescence microscopy, there were no major differences in distribution of sympathetic and parasympathetic nerves present in the lpr conjunctiva compared to that of +/+ mice at any ages, although slight differences were observed with increased age. Muscarinic receptor expression was decreased, as less M(3) receptor subtype-associated immunofluorescence was detected in older lpr mice compared to +/+ mice and confirmed by Western blot analysis. No differences in the localization or the amount of alpha(1)- or beta(1-3)-adrenergic receptor immunodetection were observed between lpr and +/+ mice. We conclude that the conjunctiva is a target tissue in Sjögren's syndrome-related inflammation in this murine model.
Asunto(s)
Conjuntiva/inmunología , Células Caliciformes/patología , Síndrome de Sjögren/inmunología , Linfocitos T/inmunología , Animales , Western Blotting/métodos , Recuento de Células , Conjuntiva/química , Conjuntiva/patología , Proteína Ligando Fas/genética , Femenino , Queratina-7/análisis , Mediciones Luminiscentes , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos MRL lpr , Microscopía Fluorescente , Modelos Animales , Mutación , Proteína Quinasa C/análisis , Receptores Adrenérgicos/análisis , Receptores Muscarínicos/análisis , Síndrome de Sjögren/metabolismo , Síndrome de Sjögren/patologíaRESUMEN
Changes in the patterns of production and in the effects of signal substances may be involved in the development of tendinosis, a chronic condition of pain in human tendons. There is no previous information concerning the patterns of sympathetic innervation in the human patellar tendon. In this study, biopsies of normal and tendinosis patellar tendons were investigated with immunohistochemical methods, including the use of antibodies against tyrosine hydroxylase (TH) and neuropeptide Y, and against alpha1-, alpha2A-, and beta1-adrenoreceptors. It was noticed that most of the sympathetic innervation was detected in the walls of the blood vessels entering the tendon through the paratendinous tissue, and that the tendon tissue proper of the normal and tendinosis tendons was very scarcely innervated. Immunoreactions for adrenergic receptors were noticed in nerve fascicles containing both sensory and sympathetic nerve fibers. High levels of these receptors were also detected in the blood vessel walls; alpha1-adrenoreceptor immunoreactions being clearly more pronounced in the tendinosis tendons than in the tendons of controls. Interestingly, immunoreactions for adrenergic receptors and TH were noted for the tendon cells (tenocytes), especially in tendinosis tendons. The findings give a morphological correlate for the occurrence of sympathetically mediated effects in the patellar tendon and autocrine/paracrine catecholamine mechanisms for the tenocytes, particularly, in tendinosis. The observation of adrenergic receptors on tenocytes is interesting, as stimulation of these receptors can lead to cell proliferation, degeneration, and apoptosis, events which are all known to occur in tendinosis. Furthermore, the results imply that a possible source of catecholamine production might be the tenocytes themselves
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Catecolaminas/biosíntesis , Ligamento Rotuliano/inervación , Receptores Adrenérgicos/análisis , Sistema Nervioso Simpático/química , Tendinopatía/patología , Adulto , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Ligamento Rotuliano/patología , Sistema Nervioso Simpático/enzimología , Tendinopatía/etiología , Tendinopatía/metabolismo , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
BACKGROUND: During development, AV conduction switches from base-to-apex to apex-to-base conduction after emergence of the conduction system. We hypothesize that after this transition, the bulk of the AV ring, although no longer required for AV conduction, remains transiently able to conduct, providing a potential arrhythmia substrate. We studied AV conduction during this transition and its sensitivity to autonomic modulation. METHODS AND RESULTS: Simultaneous voltage and Ca2+ mapping with RH-237 and Rhod-2 was performed with 2 CCD cameras in embryonic mouse hearts (n = 43). Additionally, isolated calcium mapping was performed in 309 hearts with fluo-3AM. Propagation patterns in voltage and Ca2+ mapping coincided. Arrhythmias were uncommon under basal conditions, with AV block in 14 (4%) and junctional rhythms in 4 (1%). Arrhythmias increased after stimulation with isoproterenol-junctional rhythm in 9 (3%) and ventricular rhythms in 22 (6%)-although AV block decreased (3 hearts, 1%). Adding carbachol after isoproterenol caused dissociated antegrade and retrograde AV ring conduction in 30 (8.6%) of E10.5 and E11.5 hearts, occurring preferentially in the right and left sides of the ring, respectively. In 2 cases, reentry occurred circumferentially around the AV ring, perpendicular to normal propagation. Reentry persisted for multiple beats, lasting from 3 to 22 minutes. No episodes of AV ring reentry occurred in E9.5 hearts. CONCLUSIONS: AV ring reentry can occur by spatial dissociation of antegrade and retrograde conduction during combined adrenergic and muscarinic receptor stimulation. Critical maturation (> E9.5) seems to be required to sustain reentry.
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Nodo Atrioventricular/fisiología , Sistema de Conducción Cardíaco/fisiología , Corazón/embriología , Corazón/fisiología , Taquicardia por Reentrada en el Nodo Atrioventricular/fisiopatología , Agonistas Adrenérgicos beta/farmacología , Animales , Arritmias Cardíacas/fisiopatología , Calcio/análisis , Carbacol/farmacología , Cardiotónicos/farmacología , Corazón/efectos de los fármacos , Isoproterenol/farmacología , Ratones , Miocardio/química , Receptores Adrenérgicos/análisis , Receptores Adrenérgicos/fisiología , Receptores Muscarínicos/análisis , Receptores Muscarínicos/fisiologíaRESUMEN
Neural and paracrine agents, such as dopamine, epinephrine, and histamine, affect intestinal epithelial function, but it is unclear if these agents act on receptors directly at the enterocyte level. The cellular localization and villus-crypt distribution of adrenergic, dopamine, and histamine receptors within the intestinal epithelium is obscure and needs to be identified. Single cell populations of villus or crypt epithelial cells were isolated from the jejunum of adult guinea pigs. Enterocytes were separated from intraepithelial lymphocytes by flow cytometry and specific binding was determined using fluorescent probes. Alpha1-adrenergic receptors were located on villus and crypt intraepithelial lymphocytes and enterocytes. Beta-adrenergic receptors were found on villus and crypt enterocytes. Dopamine receptors were found on all cell types examined, whereas histamine receptors were not detected (<10% for each cell population). These studies demonstrated that (1) receptors for epinephrine and dopamine exist on epithelial cells of the guinea pig jejunum, (2) beta-adrenergic receptors are found primarily on villus and crypt enterocytes and (3) intraepithelial lymphocytes contain alpha1-adrenergic, but have few beta-adrenergic, receptors. The presence of neural receptors suggests that these agents are acting, at least in part, at the enterocyte or intraepithelial lymphocyte levels to modulate intestinal and immune function.
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Células Epiteliales/metabolismo , Yeyuno/metabolismo , Receptores Adrenérgicos/análisis , Receptores Dopaminérgicos/análisis , Receptores Histamínicos/análisis , Animales , Separación Celular , Células Cultivadas , Enterocitos/metabolismo , Citometría de Flujo , Colorantes Fluorescentes , Cobayas , Masculino , Receptores Adrenérgicos beta/análisisRESUMEN
The distribution of leukocytes is regulated by the autonomic nervous system in humans and animals. The number and function of granulocytes are stimulated by sympathetic nerves whereas those of lymphocytes are stimulated by parasympathetic nerves. This is because granulocytes bear adrenergic receptors, but lymphocytes bear cholinergic receptors on the surface. These regulations may be beneficial to protect the body of living beings. However, when the autonomic nervous system deviates too much to one direction, we fall victim to certain diseases. For example, severe physical or mental stress --> sympathetic nerve activation --> granulocytosis --> tissue damage, including collagen diseases, inflammatory bowel diseases, and cancer. If we introduce the concept of immunomodulation by the autonomic nervous system, a new approach for collagen diseases, inflammatory bowel diseases, and even cancer is raised. With this approach, we believe that these diseases are no longer incurable.
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Sistema Nervioso Autónomo/inmunología , Tolerancia Inmunológica/inmunología , Receptores Colinérgicos/análisis , Animales , Antiinflamatorios no Esteroideos/farmacología , Diferenciación Celular/inmunología , Colitis Ulcerosa/inmunología , Enfermedades del Colágeno/inmunología , Enfermedad de Crohn/inmunología , Humanos , Leucocitos/química , Neoplasias/inmunología , Receptores Adrenérgicos/análisis , Úlcera Gástrica/inmunología , Estrés Fisiológico/inmunologíaRESUMEN
The aim of the study was to determine whether relations do exist between the concentration and activity of alpha(1)-adrenoceptors, both inside the prostatic adenoma and the periurethral zone corresponding to the bladder neck, and clinical and biological parameters such as symptoms, evaluated by the American Urological Association (AUA) score, age, weight of the prostate, PSA, and the flow rate. Twenty patients with symptomatic benign prostatic hyperplasia were selected for an open prostatectomy. One gram of tissue was dissected from inside the adenoma and 1 g from the periurethral zone corresponding to the bladder neck. The alpha(1)-adrenoceptors were evaluated for the apparent dissociation constant (K(d)) and the maximal number of binding sites (B(max)). A correlation seems to exist between receptor density inside the adenoma and the bladder neck and an inverse correlation between receptor density and the AUA total symptoms score. Finally, a highly significant difference was found in patients with an AUA score of <15 or >15. No relationship was found between receptor binding affinity and the considered clinical parameters.
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Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/metabolismo , Receptores Adrenérgicos/metabolismo , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Unión Proteica , Receptores Adrenérgicos/análisisRESUMEN
PURPOSE: Interstitial cystitis is a chronic syndrome affecting humans and domestic animals, including cats (feline interstitial cystitis). The aggravation of interstitial cystitis symptoms by stress suggests involvement of the sympathetic nervous system. Studies have identified increased sympathetic nervous system activity in patients with interstitial cystitis but to our knowledge effects on bladder function have not been reported. To address this question we measured bladder norepinephrine (NE) content, the electrical field stimulation flux of NE and acetylcholine (ACh), and the effects of feline interstitial cystitis on adrenoceptor (AR) mediated bladder strip contractility. MATERIALS AND METHODS: Bladders were obtained from healthy cats and cats with feline interstitial cystitis. In experiment 1 bladder tissue NE content was determined and the simultaneous release of 3H-NE and 14C-ACh in perfusion bath effluent after electrical field stimulation was measured. NE and ACh release was calculated from the area under the efflux curve. In experiment 2 electrical field stimulation induced contractility of bladder body strips was measured in the presence of 100 nM. to 25 microM. NE only or combined with atipamezole (an alpha2-AR antagonist), propranolol (a beta-AR antagonist) or phentolamine (an alpha-AR antagonist). Antagonists were added to the bath at least 15 minutes before stimulation, after which NE was added in cumulative doses and dose response curves were constructed. RESULTS: Significant increases in NE content and efflux in the absence of alterations in ACh efflux were identified. In the bladder strip studies decreased alpha2 and beta1-AR function was found in strips from cats with feline interstitial cystitis, whereas beta3 or atypical beta-ARs were tentatively identified. CONCLUSIONS: These results support and extend previous studies by identifying an effect of increased sympathetic activity on bladder function in cats with feline interstitial cystitis.
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Enfermedades de los Gatos/fisiopatología , Cistitis Intersticial/veterinaria , Norepinefrina/análisis , Receptores Adrenérgicos/análisis , Vejiga Urinaria/química , Animales , Gatos , Cistitis Intersticial/fisiopatología , Estimulación Eléctrica , Contracción Muscular , Músculo Liso/fisiopatología , Vejiga Urinaria/fisiopatologíaRESUMEN
Adrenergic receptors (ARs) are involved in regulating saliva secretion and composition in salivary glands. Nine AR subtypes, including three alpha1-ARs (alpha1a-, alpha1b- and alpha1d-ARs), three alpha2-ARs (alpha2A-, alpha2B- and alpha2C-ARs) and three beta-ARs (beta1,beta2- and beta3-ARs), have been identified through molecular cloning. The five subtype genes, alpha1a-, alpha1b-, alpha2A-, beta1-, and beta2-ARs, were expressed in rat submandibular glands. In contrast, the other four subtype mRNAs, alpha1d-, alpha2B-, alpha2C- and beta3-ARs, were not detected by reverse transcription-polymerase chain reaction (RT-PCR). The steady-state mRNA expression for the five AR subtypes in rat submandibular glands was measured by quantitative competitive RT-PCR using synthetic DNA as internal standard at different stages of postnatal development. The relative rank order of AR subtype mRNA expression was alpha1a>beta2>beta1>alpha2A>alpha1b at all stages except that beta1- and alpha2A-subtypes were reversed at 2 weeks of age. The gene expression of alpha1a-AR subtype relative to total AR was low at 2 weeks of age and increased and reached a maximum at 6 weeks of age, whereas those patterns of alpha2A-, beta1- and beta2-AR subtypes were similar to each other and their gene expressions were high at 2 weeks of age and then decreased. On the other hand, the gene expression of alpha1b-AR subtype did not change over the different stages in relation to that of a housekeeping gene, glyceraldehyde 3-phosphate dehydrogenase, and to total AR. Although rat submandibular glands contain the five AR subtype mRNAs, distinct subtype-specific expression is evident.