Ofner and S

Ofner and S. of rats with terbutaline (0.3?mg?kg?1, s.c. 30?min before the second antigen challenge) suppressed antigen-induced elevation of protein and eosinophil leukocytes, and reduced the concentration of NGF in BAL to ideals much like those found in non-sensitized rats. The present results demonstrate anti-allergic properties of terbutaline in rats that were accompanied by a marked reduction of antigen-induced NGF increase in pores and skin and BAL, respectively. These results are compatible with the assumption that terbutaline primarily suppressed the immune response to antigen therefore attenuating the release of vasoactive mediators and the activation of NGF biosynthesis. antigen-induced histamine launch in preparations of peritoneal cells as explained previously 3-Nitro-L-tyrosine (Schuligoi, 1998): Anaesthetized rats were exsanguinated, and peritoneal lavage was performed with Tris/HCl 25?mM, pH 7.8, containing NaCl 120?mM, KCl 5?mM, gelatine 0.1% and heparin 10?U?ml?1. After centrifugation (10?min, 300?g), the pellet was washed twice with Tris/HCl 25?mM, pH 7.8 (containing (mM): NaCl 120, KCl 5, gelatine 3-Nitro-L-tyrosine 0.1%), resuspended in Tris/HCl 25?mM, pH 7.6 (containing (mM): NaCl 120, KCl 5, gelatine 0.1%). The cells were incubated for 15?min at 37C, thereafter L–phosphatidyl-L-serine (10?g?ml?1, final concentration, Sigma) together with ovalbumin (50?ng?ml?1) was added to the aliquots. After another 30?min incubation, samples were centrifuged (10?min, 300for 10?min and the supernatant utilized for dedication of protein content material (Bio-Rad Protein Assay, Vienna, Austria) and immunoreactive NGF. Cells were re-suspended in 1?ml PBS and the cell number was counted using Cobas Minos Vet (Roche, Mannheim, Germany). Medicines Terbutaline sulphate and (?)-propranolol hydrochloride, were from Sigma and dissolved in 0.9% NaCl. All doses of drugs refer to the base. Statistical analysis Ideals were determined as meanss.e.mean. Unless stated otherwise, statistical analysis was performed using ONE OF THE 3-Nitro-L-tyrosine WAYS ANOVA, or Kruskal Wallis ONE OF THE WAYS Analysis of Vegfc Variance, when appropriate, using Dunnett’s or Dunn’s post-test respectively (SigmaStat statistical software, Jandel Scientific, Erkrath, Germany). addition of ovalbumin (50?ng?ml?1) to peritoneal cells from sensitized rats induced a significant launch of histamine (40.837.91% of the total content; 1.910.10?pg?g?1; immunoneutralization with anti-NGF antibody prevents the development of airway hyperreactivity after antigen exposure (Braun et al., 1998). Consequently, it seems of interest that our results display that terbutaline attenuated the increase of NGF in BAL of rats challenged with aerosolized antigen. As to the probable modes of action, similar possibilities arise as resolved above: The assumption that terbutaline interfered with the immune response itself is compatible with the observation that terbutaline also inhibited the increase of protein concentration and eosinophil cell number in BAL. However, these results also provide reason to be cautious in extrapolating these findings to the situation in individuals. Although there are studies showing a decrease of allergen-induced vascular permeability (Bolton et al., 1997; Proud et al., 1998) and eosinophil infiltration (Bowden et al., 1994; Dente et al., 1999), many studies find no major anti-inflammatory effects by beta adrenergic agonists (Gardiner et al., 1994; Roberts et al., 1999; Turner et al., 1998). It remains to be investigated, therefore, whether or not attenuation of antigen-induced NGF increase can also be observed in individuals receiving beta adrenergic agonists. Acknowledgments The authors would like to say thanks to I. Lanz, M. Ofner and S. Dirnberger for expert technical assistance. The study was supported by Fonds zur F?rderung der wissenschaftlichen Forschung (FWF P-13512-Med). Abbreviations BALbronchoalveolar lavageELISAenzyme-linked immunosorbent assayGAPDHglyceraldehyde-3 phosphate dehydrogenaseNGFnerve growth factorPBSphosphate buffered salineRT?C?PCRreverse transcription polymerase chain reaction.