Facilitating folding of outer membrane proteins, roles of the periplasmic chaperone Skp and the outer membrane lipoprotein BamD

This thesis describes several important advancements in the understanding of the assembly of outer membrane proteins of Gram-negative bacteria like Escherichia coli. A first study was performed to identify binding regions in the trimeric chaperone Skp for outer membrane proteins. Skp is known to facilitate the passage of unfolded outer membrane proteins (OMPs) through the periplasm to the outer membrane (OM). A gene construct named “synthetic chaperone protein (scp)” gene was used to express a fusion protein (Scp) into the cytoplasm of E. coli. The scp gene was used as a template to design mutants of Scp suitable for structural and functional studies using site-directed spectroscopy. Fluorescence resonance energy transfer (FRET) was used to identify distances in Skp-OmpA complexes that separate regions in Scp and in outer membrane protein A (OmpA) from E. coli. For this study, single cysteine (Cys) mutants and single Cys - single tryptophan (Trp) double mutants of Scp were prepared. For FRET experiments, the cysteines were labeled with the tryptophan fluorescence energy acceptor IAEDANS. Single Trp mutants of OmpA were used as fluorescence energy donors. In the second part of this thesis, the function of BamD and the structure of BamD-Scp complexes were examined. BamD is an essential component of the β-barrel assembly machinery (BAM) complex of the OM of Gram-negative bacteria. Fluorescence spectroscopy was used to probe the interactions of BamD with lipid membranes and to investigate the interactions of BamD with possible partner proteins from the periplasm and from the OM. A range of single cysteine (Cys) and single tryptophan (Trp) mutants of BamD were prepared. A very important conclusion from the extensive FRET study is that the essential lipoprotein BamD interacts and binds to the periplasmic chaperone Skp. BamD contains tetratrico peptide repeat (TPR) motifs that are suggested to serve as docking sites for periplasmic chaperones such as Skp.

SVET, SKP and EIS study of the corrosion behaviour of high strength Al and Al-Li alloys used in aircraft fabrication

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Stalinismin lyhyt kurssi : Suomalaiset Moskovan Lenin-koulussa 1926-1938

This study of the Finns at the International Lenin School (ILS) reflects history of the Soviet Union during Stalin's era, history of the Communist International (Comintern) as well as history of Finnish communism. The life span of the ILS (1926-1938) matches up with creating and establishing the power structures of Stalinism. Both the ILS and Finnish Communism in the USSR became casualties of the Great Terror (1937-1938). After the WW2, however, the Soviet education was appreciated inside the Communist Party of Finland (CPF). If Finland would have become People's Democracy, the former ILS students would have composed the inner circle of the new "democratic" government. The Finnish teachers of the ILS were leaders of the CPF that was headquartered in Moscow. At the ILS studied in total 141 Finnish communists. The purpose of the ILS was to educate the communist parties' leading stratum of functionaries. They were supposed to internalize current values, methods and discipline of the Bolsheviks. This study evaluates the effects of the total school experience on the Finns that often ended in another total institution in Finland: prison. The curricula of the ILS consisted of theory of Marxism-Leninism, party history, political economics and themes of campaigns of Stalinism. The ILS year included participation in Bolshevik party life and practical work. During summer excursions (praktikas) the students could acquaint themselves with building of socialism in the Soviet Republics. At the ILS, intention to ideological moulding was not hidden. The students were supposed to adopt the Stalinist identity of the professional revolutionaries of the era. The ILS was saturated with ideology and propaganda. This study analyzes especially uses of history as vehicle of ideological standardisation and as instrument of power. Stalin contributed personally to shortcomings of history writing of the communist party. Later he supervised writing of the inclusive handbook of communism, "History of the All-Union Communist Party. Short Course". Special attention will be paid to the effects of Stalin's intervention at the ILS and inside the CPF. The life of the Finns at the ILS and outside the school is described at grass roots. The dividing line between personal and political is analyzed by charting emotional, intimate and bodily experiences of the Finns of the ILS. The fates of the ILS Finns after the studying or teaching period in Moscow are explored in detail. The protagonist among the teachers is Yrjö Sirola that was called "father of the CPF cadres". The Finnish ILS teachers and the formed students that had remained in the USSR were most severely hit by the Great Terror. The Soviet education had most importance in Finland of post WW2 period. The training at the ILS, however, did not contribute to revolution in Finland. The main heading of the study, "A Short Course of Stalinism", crystallises interpretation of the ILS as seat of learning of ideological unity of Stalinism. On the other hand, the title includes a statement of incompleteness of the Stalinist education if the schooling at the ILS had remained in one year.

Koko kansan koti vai kommunistien pesäke? Helsingin Kulttuuritalon rakentaminen ja paikan henki 1955-1959

Helsingin Kulttuuritalo rakennettiin vuosina 1955–1958 vastaamaan Suomen kommunistisen puolueen ja muiden kansandemokraattisten järjestöjen toimitilojen puutteeseen. Kulttuuritalo oli myös kommunistien vastaus Helsingissä jo 1900-luvun alusta lähtien käytyyn konserttisali keskusteluun. Kulttuuritalo rakennettiin SKP:n päämajaksi, mutta sinne asettui myös lukuisia muita kansandemokraattisia järjestöjä. Kulttuuritalon suunnitteli professori Alvar Aalto. Pro gradu -tutkielmassani olen tarkastellut Helsingin Kulttuuritalon rakentamista ja paikan hengen muodostumista vuosien 1955–1959 välillä. Aikarajaus kattaa Kulttuuritalon rakennusvuodet sekä sen ensimmäisen kokonaisen toimintavuoden. Tutkielman ensisijaiset tutkimuskysymykset ovat: Miksi Helsingin Kulttuuritalo rakennettiin, millainen rakennusprosessi oli ja millainen paikan henki Kulttuuritalolle muodostui vuosien 1955–1959 aikana? Teoreettisen viitekehyksen tutkielmalle muodostaa paikan hengen käsite. Primäärilähteinä tutkielmassa ovat Kansan Arkistosta löytyvät Kulttuuritalo Oy:n ja Kulttuurityö ry:n kokoelmat sekä sanomalehdet. Sanomalehtiä käytetään Kulttuuritalon paikan hengen ilmentämiseen. Kulttuuritalo rakennettiin pääasiassa talkoovoimin. Talkoisiin osallistui runsaasti ihmisiä niin pääkaupunkiseudulta kuin ulkopaikkakunnilta. Suurin osa Kulttuuritalon rakentamisen rahoituksesta tuli kommunistisilta poliittisilta järjestöiltä ja ammattijärjestöiltä. Pyynnöistä huolimatta Helsingin kaupungilta tai Suomen valtiolta ei tippunut tukea kommunistien hankkeelle. NKP osallistui Kulttuuritalon rakennuskustannuksiin sekä suorin tavaralahjoituksia että epäsuoraan Bukarestissa sijainneen kansainvälisen rahaston kautta, joka toimi SKP:n rahoittajana. Kulttuuritalon paikan hengen luominen liittyi tiiviisti Kulttuuritalon rakentamiseen, sillä paikan henki alkoi muodostua jo talon rakennusvaiheessa. Kulttuuritalon paikan hengen rakentamiseen osallistuivat niin kommunistit ja kansandemokraatit kuin kommunismin vastustajat. Kommunismin vastustajilla tarkoitan tutkielmassa oikeistoa ja sosiaalidemokraatteja. Kommunismin vastustajat vastustivat tavallisesti myös Kulttuuritaloa, mikä kytkee 1950-luvun suomalaisen antikommunismin Kulttuuritalon paikan hengen muodostamiseen. Kun kommunistit rakensivat Kulttuuritalon paikan hengen positiivista puolta, sosiaalidemokraatit ja oikeistolaiset lehdet osallistuivat sen negatiivisen puolen muodostamiseen. Kulttuuritalon paikan hengestä muodostui vuosien 1955–1959 aikana voimakkaan punainen. Kulttuuritalon punaisuus sai kuitenkin kaksi merkitystä: Kommunisteille ja kansandemokraateille se merkitsi työväenliikkeen solidaarisuutta, tasa-arvoa ja voimaa. Kulttuuritalo oli heille osoitus työväen voimasta, ja he toivoivat sen auttavan kommunisteja saavuttamaan laajemman kannatuksen ja hyväksytyn aseman yhteiskunnassa. Kommunismin vastustajille Kulttuuritalo puolestaan merkitsi perinteistä yhteiskuntaa uhkaavaa tekijää. Kulttuuritalon oli heidän mielestään vaarallinen paikka, jonka avulla kommunistit pyrkivät vahvistamaan asemiaan yhteiskunnassa. Kulttuuritalon paikan henki heijasti näin suomalaisen yhteiskunnan kahtiajakautuneisuutta. Kulttuuritalon paikan henki vaikutti myös talon käyttöön. Kulttuuritalon ottivat innolla omakseen kommunistit ja kansandemokraatit, mutta sosiaalidemokraatit ja oikeistolaiset eivät halunneet sitä käyttää, vaikka Kulttuuritalon juhlasali olikin Helsingissä ainoa, joka täytti kansainvälisestikin tasokkaan akustiikan vaatimukset.

Koko kansan koti vai kommunistien pesäke? Helsingin Kulttuuritalon rakentaminen ja paikan henki 1955-1959

Helsingin Kulttuuritalo rakennettiin vuosina 1955–1958 vastaamaan Suomen kommunistisen puolueen ja muiden kansandemokraattisten järjestöjen toimitilojen puutteeseen. Kulttuuritalo oli myös kommunistien vastaus Helsingissä jo 1900-luvun alusta lähtien käytyyn konserttisali keskusteluun. Kulttuuritalo rakennettiin SKP:n päämajaksi, mutta sinne asettui myös lukuisia muita kansandemokraattisia järjestöjä. Kulttuuritalon suunnitteli professori Alvar Aalto. Pro gradu -tutkielmassani olen tarkastellut Helsingin Kulttuuritalon rakentamista ja paikan hengen muodostumista vuosien 1955–1959 välillä. Aikarajaus kattaa Kulttuuritalon rakennusvuodet sekä sen ensimmäisen kokonaisen toimintavuoden. Tutkielman ensisijaiset tutkimuskysymykset ovat: Miksi Helsingin Kulttuuritalo rakennettiin, millainen rakennusprosessi oli ja millainen paikan henki Kulttuuritalolle muodostui vuosien 1955–1959 aikana? Teoreettisen viitekehyksen tutkielmalle muodostaa paikan hengen käsite. Primäärilähteinä tutkielmassa ovat Kansan Arkistosta löytyvät Kulttuuritalo Oy:n ja Kulttuurityö ry:n kokoelmat sekä sanomalehdet. Sanomalehtiä käytetään Kulttuuritalon paikan hengen ilmentämiseen. Kulttuuritalo rakennettiin pääasiassa talkoovoimin. Talkoisiin osallistui runsaasti ihmisiä niin pääkaupunkiseudulta kuin ulkopaikkakunnilta. Suurin osa Kulttuuritalon rakentamisen rahoituksesta tuli kommunistisilta poliittisilta järjestöiltä ja ammattijärjestöiltä. Pyynnöistä huolimatta Helsingin kaupungilta tai Suomen valtiolta ei tippunut tukea kommunistien hankkeelle. NKP osallistui Kulttuuritalon rakennuskustannuksiin sekä suorin tavaralahjoituksia että epäsuoraan Bukarestissa sijainneen kansainvälisen rahaston kautta, joka toimi SKP:n rahoittajana. Kulttuuritalon paikan hengen luominen liittyi tiiviisti Kulttuuritalon rakentamiseen, sillä paikan henki alkoi muodostua jo talon rakennusvaiheessa. Kulttuuritalon paikan hengen rakentamiseen osallistuivat niin kommunistit ja kansandemokraatit kuin kommunismin vastustajat. Kommunismin vastustajilla tarkoitan tutkielmassa oikeistoa ja sosiaalidemokraatteja. Kommunismin vastustajat vastustivat tavallisesti myös Kulttuuritaloa, mikä kytkee 1950-luvun suomalaisen antikommunismin Kulttuuritalon paikan hengen muodostamiseen. Kun kommunistit rakensivat Kulttuuritalon paikan hengen positiivista puolta, sosiaalidemokraatit ja oikeistolaiset lehdet osallistuivat sen negatiivisen puolen muodostamiseen. Kulttuuritalon paikan hengestä muodostui vuosien 1955–1959 aikana voimakkaan punainen. Kulttuuritalon punaisuus sai kuitenkin kaksi merkitystä: Kommunisteille ja kansandemokraateille se merkitsi työväenliikkeen solidaarisuutta, tasa-arvoa ja voimaa. Kulttuuritalo oli heille osoitus työväen voimasta, ja he toivoivat sen auttavan kommunisteja saavuttamaan laajemman kannatuksen ja hyväksytyn aseman yhteiskunnassa. Kommunismin vastustajille Kulttuuritalo puolestaan merkitsi perinteistä yhteiskuntaa uhkaavaa tekijää. Kulttuuritalon oli heidän mielestään vaarallinen paikka, jonka avulla kommunistit pyrkivät vahvistamaan asemiaan yhteiskunnassa. Kulttuuritalon paikan henki heijasti näin suomalaisen yhteiskunnan kahtiajakautuneisuutta. Kulttuuritalon paikan henki vaikutti myös talon käyttöön. Kulttuuritalon ottivat innolla omakseen kommunistit ja kansandemokraatit, mutta sosiaalidemokraatit ja oikeistolaiset eivät halunneet sitä käyttää, vaikka Kulttuuritalon juhlasali olikin Helsingissä ainoa, joka täytti kansainvälisestikin tasokkaan akustiikan vaatimukset.

Pion Production in Heavy-ion Collisions in the 1 A GeV region

Within the framework of the improved isospin dependent quantum molecular dynamics (ImIQMD) model, the pion emission in heavy-ion collisions in the region 1AGeV is investigated systematically, in which the pion is considered to be mainly produced by the decay of resonances ∆(1232) and N∗(1440). The in-medium dependence and Coulomb effects of the pion production are included in the calculation. Total pion multiplicity and π−/π+ yields are calculated for the reaction 197Au+197Au in central collisions for selected Skyrme parameters SkP, SLy6,Ska, SIII and compared them with the measured data by the FOPI collaboration.

Pion Production in Heavy-Ion Collisions in the 1 A GeV Region

Within the framework of the improved isospin dependent quantum molecular dynamics (ImIQMD) model, pion emission in heavy-ion collisions in the region 1 A GeV is investigated systematically, in which the pion is considered to be mainly produced by the decay of resonances Delta(1232) and N*(1440). The in-medium dependence and Coulomb effects of pion production are included in the calculation. Total pion multiplicity and pi(-)/pi(+) yields are calculated for the reaction Au-197+(197) Au in central collisions for selected Skyrme parameters SkP, SLy6, Ska, SIII and compared with the measured data of the FOPI collaboration.

Probing high-density behavior of symmetry energy from pion emission in heavy-ion collisions

Within the framework of the improved isospin dependent quantum molecular dynamics (ImIQMD) model, the emission of pion in heavy-ion collisions in the region 1 A GeV as a probe of nuclear symmetry energy at supra-saturation densities is investigated systematically, in which the pion is considered to be mainly produced by the decay of resonances Delta(1232) and N*(1440). The total pion multiplicities and the pi(-)/pi(+) yields are calculated for selected Skyrme parameters SkP, SLy6. Ska and SIB, and also for the cases of different stiffness of symmetry energy with the parameter SLy6. Preliminary results compared with the measured data by the FOPI Collaboration favor a hard symmetry energy of the potential term proportional to (rho/rho(0))(gamma s) with gamma(s) = 2. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.

Dynamics of pion production in heavy-ion collisions around 1A GeV energies

Within the framework of the improved isospin-dependent quantum molecular dynamics model, the dynamics of pion emission in heavy-ion collisions in the region of 1A GeV energies as a probe of nuclear symmetry energy at suprasaturation densities is investigated systematically. The total pion multiplicities and the pi(-)/pi(+) yields are calculated for selected Skyrme parameters SkP, SLy6, Ska, and SIII and also for the cases of different stiffness of symmetry energy with the parameter SLy6. The influence of Coulomb potential, symmetry energy, and in-medium pion potential on the pion production is investigated and compared to each other by analyzing the distributions of transverse momentum and longitudinal rapidity and also the excitation functions of the total pion and the pi(-)/pi(+) ratio. The directed flow, elliptic flow, and polar-angle distributions are calculated for the cases of different collision centralities and also the various stiffnesses of the symmetry energies. A comparison of the calculations with the available experimental data is performed.

PROBING THE SYMMETRY ENERGY AT SUPRA-SATURATION DENSITIES FROM PION EMISSION IN HEAVY-ION COLLISIONS

Within the framework of the improved isospin dependent quantum molecular dynamics (ImIQMD) model, the emission of pion in heavy-ion collisions in the region 1 A GeV as a probe of nuclear symmetry energy at supra-saturation densities is investigated systematically, in which the pion is considered to be mainly produced by the decay of resonances Delta(1232) and N*(1440). The pi(-)/pi(+) yields are calculated for selected Skyrme parameters SkP, SLy6, Ska and SIII, and also for the cases of different stiffness of symmetry energy with the parameter SLy6. Preliminary results compared with the measured data by the FOPI collaboration favor a hard symmetry energy of the potential term proportional to (rho/rho(0))(gamma s) with gamma(s) = 2.

Identification, Characterization, and Molecular Application of a Virulence-Associated Autotransporter from a Pathogenic Pseudomonas fluorescens Strain

A gene, pfa1, encoding an autotransporter was cloned from a pathogenic Pseudomonas fluorescens strain, TSS, isolated from diseased fish. The expression of pfa1 is enhanced during infection and is regulated by growth phase and growth conditions. Mutation of pfa1 significantly attenuates the overall bacterial virulence of TSS and impairs the abilities of TSS in biofilm production, interaction with host cells, modulation of host immune responses, and dissemination in host blood. The putative protein encoded by pfa1 is 1,242 amino acids in length and characterized by the presence of three functional domains that are typical for autotransporters. The passenger domain of PfaI contains a putative serine protease (Pap) that exhibits apparent proteolytic activity when expressed in and purified from Escherichia coli as a recombinant protein. Consistent with the important role played by PfaI in bacterial virulence, purified recombinant Pap has a profound cytotoxic effect on cultured fish cells. Enzymatic analysis showed that recombinant Pap is relatively heat stable and has an optimal temperature and pH of 50 degrees C and pH 8.0. The domains of PfaI that are essential to autotransporting activity were localized, and on the basis of this, a PfaI-based autodisplay system (named AT1) was engineered to facilitate the insertion and transport of heterologous proteins. When expressed in E. coli, AT1 was able to deliver an integrated Edwardsiella tarda immunogen (Et18) onto the surface of bacterial cells. Compared to purified recombinant Et18, Et18 displayed by E. coli via AT1 induced significantly enhanced immunoprotection.

Effects of spark discharge on the anodic coatings on magnesium alloy

Spark discharge was the representative phenomenon of Micro-arc oxidation (MAO) method distinguished from other electrochemical oxidation methods. Under the spark discharge treatment, characteristics of the anodic layer were significantly changed. To investigate the influences of the spark discharge, a piece of magnesium alloy AZ91D specimen was partly treated by MAO method in alkaline silicate solution. And the microstructure, element distributions as well as the surface potential distributions of the specimen were studied by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and scanning Kelvin probe (SKP) technique. As a result of intensive spark discharge treatment, porous external layer with dense internal layer were formed on Mg alloy surface. At the same time, the depositions of OH- and SiO32- ions were accelerated, which resulted in the enrichment of element oxygen and silicon at the spark discharge region. Moreover, due to the compact internal layer, the intensive spark discharge region exhibited more positive potentials with respect to other regions, which meant this region could restrain the ejection of electron and provide effective protection to the substrate. In addition, it was found that oxygen played a vital role in determining the intensity and size of sparks, and abundant oxygen resulted in intensive and larger sparks. (c) 2005 Elsevier B.V. All rights reserved.

Chronic low frequency/low volume resistance training reduces pro-inflammatory cytokine protein levels and TLR4 mRNA in rat skeletal muscle

Skeletal muscle is the source of pro- and anti-inflammatory cytokines, and recently, it has been recognized as an important source of interleukin 6 (IL-6), a cytokine that exerts inhibitory effects on several pro-inflammatory cytokines. Although dynamic chronic resistance training has been shown to produce the known ""repeated bout effect"", which abolishes the acute muscle damage, performing of high-intensity resistance training has been regarded highly advisable, at least from the hypertrophy perspective. On the other hand, a more therapeutic, ""non-damaging"" resistance training program, mainly composed of concentric forces, low frequency/low volume of training, and the same exercise, could theoretically benefit the muscle when the main issue is to avoid muscle inflammation (as in the treatment of several ""low-grade"" inflammatory diseases) because the acute effect of each resistance exercise session could be diminished/avoided, at the same time that the muscle is still being overloaded in a concentric manner. However, the benefits of such ""less demanding"" resistance training schedule on the muscle inflammatory profile have never been investigated. Therefore, we assessed the protein expression of IL-6, TNF-alpha, IL-10, IL-10/TNF-alpha ratio, and HSP70 levels and mRNA expression of SCF(beta-TrCP), IL-15, and TLR-4 in the skeletal muscle of rats submitted to resistance training. Briefly, animals were randomly assigned to either a control group (S, n = 8) or a resistance-trained group (T, n = 7). Trained rats were exercised over a duration of 12 weeks (two times per day, two times per week). Detection of IL-6, TNF-alpha, IL-10, and HSP70 protein expression was carried out by western blotting and SCF(beta-TrCP) (SKP Cullin F-Box Protein Ligases), a class of enzymes involved in the ubiquitination of protein substrates to proteasomal degradation, IL-15, and TLR-4 by RT-PCR. Our results show a decreased expression of TNF-alpha and TLR4 mRNA (40 and 60%, respectively; p < 0.05) in the plantar muscle from trained, when compared with control rats. In conclusion, exercise training induced decreased TNF-alpha and TLR-4 expressions, resulting in a modified IL-10/TNF-alpha ratio in the skeletal muscle. These data show that, in healthy rats, 12-week resistance training, predominantly composed of concentric stimuli and low frequency/low volume schedule, down regulates skeletal muscle production of cytokines involved in the onset, maintenance, and regulation of inXammation.

Modulation of coronary flow and cardiomyocyte size by sensory fibers

Cardiac tissue is densely innervated by sensory neurons that an believed to play important modulatory roles in cardiac functions. In this study, pretreatment of neonate mts with capsaicin was performed. In adult rats, cardiomyocyte size and amount of fibrous tissue in left ventricles as well as in vitro coronary flow were evaluated, the chronotropic and inotropic responses to beta-adrenoceptor agonists (norepinephrine and isoproterenol), muscarinic agonists (carbachol and pilocarpine), and calcitonin gene-related peptide (CGRP) were also investigated with the use of the isolated right atria preparation. Capsaicin pretreatment significantly (P<0.05) reduced both basal coronary flow (18% reduction) and cardiomyocyte size (34% reduction) without affecting the amount of fibrous tissues in the left ventricles. The positive inotropic and chronotropic effects in response to norepinephrine in the isolated rat heart did not significantly differ between control and capsaicin-treated rats, Similarly, the positive chronotropic effects in response to norepinephrine, isoproterenol, and CGRP as well as the negative chronotropic responses to carbachol and pilocarpine in the isolated light atria were not affected by capsaicin pretreatment, Our data are consistent with the suggestion that reductions of both basal coronary flow and cardiomyocyte size seen in hearts from capsaicin-pretreated rats may be consequences of CGRP depletion. The cardiomyocyte size reduction produced by capsaicin treatment may be related to a modulatory role of CGRP as a growth factor.

Chronotropic response of beta-adrenergic-, muscarinic-, and calcitonin gene-related peptide-receptor agonists in right atria from neonatal capsaicin-treated rats

We evaluated the potency of isoproterenol, carbachol, pilocarpine and calcitonin gene-related peptide (CGRP) in the rat right atria at 30, 60 and 90 days after neonatal capsaicin treatment. Neonatal rats were pretreated on the second day of life with capsaicin (50 mg/kg). The capsaicin pretreatment caused a five-fold rightward shift at the pEC(50) level on the concentration-response curves to isoproterenol in 30-day-old rats. Propranolol (10 mg/kg, given 15 min prior to capsaicin treatment) prevented this subsensitivity. No changes in the potency of isoproterenol were observed at 60 and 90 days after capsaicin pretreatment. The potency and maximal responses of CGRP in the right atria in 30-day-old rats were significantly higher than in 60- and 90-day-old rats; however, no differences were found between control and capsaicin groups. The potency and maximal responses to carbachol and pilocarpine were not changed in all groups. The neonatal capsaicin treatment reduced by about 74% the CGRP content in the heart in all groups. In summary, capsaicin treatment in newborn rats produces a desensitization of chronotropic response mediated by beta-adrenoceptors in isolated right atria from 30-day-old rats possibly due to a massive release of catecholamines. (C) 2002 Elsevier B.V. Ireland Ltd. All rights reserved.