R.P. Tomkiewicz , E.M. App , G.T. De Sanctis , M. Coffiner , P. Maes , B.K. Rubin , M. King
{"title":"A comparison of a new mucolytic N-acetylcysteine l-lysinate with N-acetylcysteine: Airway epithelial function and mucus changes in dog","authors":"R.P. Tomkiewicz , E.M. App , G.T. De Sanctis , M. Coffiner , P. Maes , B.K. Rubin , M. King","doi":"10.1006/pulp.1995.1035","DOIUrl":"10.1006/pulp.1995.1035","url":null,"abstract":"<div><p>A newly synthesized mucolytic agent, N-acetylcysteine <span>l</span>-lysinate (Nacystelyn) was studied. Tracheal mucus velocity (TMV), tranepithelial potential difference (PD), rheological properties, and ion content of collected airway secretions were evaluated in six healthy mongrel dogs after placebo, Nacystelyn (NAL) and acetylcysteine (NAC) metered dose inhaler (MDI) aerosols. Although TMV was increased and viscoelasticity decreased after both treatments, the treatment effect with NAL was significantly greater. Furthermore, NAL increased the negative PD and Cl<sup>−</sup> content of secretions in the trachea, an effect not observed after NAC. Both compounds increased ciliary beat frequency (CBF) on the frog palate at a concentration range similar to that approximated in dog airways. The increased mucociliary clearance could be partially explained by favourable rheological changes combined with stimulation of CBF Since both compounds break disulfide bonds in mucus polymers, the greater change in mucus rheology and clearance rate after NAL, without change in water content, could be explained by the increase in Cl<sup>−</sup> content. Nacystelyn appears to combine different modes of action which synergistically cause an increase in the clearance rate of airway secretions.</p></div>","PeriodicalId":74618,"journal":{"name":"Pulmonary pharmacology","volume":"8 6","pages":"Pages 259-265"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/pulp.1995.1035","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19788417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mechanisms of 5-hydroxytryptamine-induced contraction of isolated rat intrapulmonary bronchi","authors":"J.L. Szarek, J.Z. Zhang, C.A. Gruetter","doi":"10.1006/pulp.1995.1037","DOIUrl":"10.1006/pulp.1995.1037","url":null,"abstract":"<div><p>Previous studies in our laboratory and others suggested that activation of 5-HT<sub>2</sub> receptors mediates 5-hydroxytryptamine (5-HT)-induced contraction of airway smooth muscle and that this response is dependent in part on endogenous acetylcholine (ACh). The purpose of the present study was to confirm a role for 5-HT<sub>2</sub> receptors and endogenous ACh in 5-HT-induced contraction of rat bronchi. In this study, we examined the effects of 5-HT<sub>2</sub> receptor antagonists (ketanserin and LY53857), acetylcholinesterase inhibitors (physostigmine and neostigmine), and a muscarinic receptor alkylating agent [propylbenzilylcholine mustard (PBCM) on contractile responses evoked by 5-HT and the 5-HT<sub>2</sub> receptor agonist, α-methyl-5-hydroxytryptamine (α-Me-5-HT). Concentration-response curves generated in isolated rat intrapulmonary bronchi in response to 5-HT and α-Me-5-HT were superimposable. Inhibition of acetylcholinesterase by physostigmine or neostigmine potentiated contractile responses elicited by 5-HT and α-Me-5-HT. Alkylation of muscarinic receptors with PBCM decreased maximal responses elicited by 5-HT or α-Me-5-HT in a concentration-dependent manner. Maximum contraction attained with exogenous ACh was decreased by PBCM in a concentration-dependent manner and, at the highest concentration evaluated, ACh-induced contractions were abolished. 5-Hydroxytryptamine-induced contraction was inhibited competitively by low concentrations of the 5-HT<sub>2</sub>-receptor selective antagonist, ketanserin; higher concentrations abolished contractile responses to the amine. The inhibition of 5-HT-induced contractile responses by another 5-HT<sub>2</sub>-receptor selective antagonist, LY53857, was non-competitive in nature. Together, the results suggest that 5-HT contracts rat airways directly by activating 5-HT<sub>2</sub> receptors located on airway smooth muscle and indirectly by activation of 5-HT<sub>2</sub> receptors on parasympathetic nerve endings to cause release of ACh. The potential physiological implication of these findings is that 5-HT released in inflammatory conditions such as asthma may play a role in causing bronchoconstriction by releasing ACh or by augmenting release of ACh from activated cholinergic nerves.</p></div>","PeriodicalId":74618,"journal":{"name":"Pulmonary pharmacology","volume":"8 6","pages":"Pages 273-281"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/pulp.1995.1037","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19787650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. O'Connor, G.C. Kane, M. Tolino, M. Pollice, J.E. Fish, S.P. Peters
{"title":"Inhaled albuterol does not inhibit cellular influx or lung injury produced by segmental antigen challenge in humans","authors":"J. O'Connor, G.C. Kane, M. Tolino, M. Pollice, J.E. Fish, S.P. Peters","doi":"10.1006/pulp.1995.1032","DOIUrl":"10.1006/pulp.1995.1032","url":null,"abstract":"<div><p>Many experimental protocols and published guidelines for performing bronchoscopy, bronchoalveolar lavage (BAL), bronchial biopsies, and segmental antigen challenge (SAC) of allergic asthmatic subjects recommend treating subjects with a <em>β</em>-agonist prior to the procedure. However, the effect of <em>β</em>-agonist pretreatment has not been reported. In a retrospective analysis of ragweed allergic subjects undergoing bronchoscopy, SAC, and BAL, we examined the effect of albuterol pretreatment on cellular influx and lung injury produced by antigen challenge. Forty-eight subjects, 17 who received no pretreatment and 31 who received four puffs of albuterol prior to bronchoscopy, comprised the study groups. No parameter monitored in BAL fluid 24 h after SAC (total cells, macrophages, neutrophils, eosinophiis, lymphocytes, total protein, albumin, or eosinophil cationic protein) differed in subjects pretreated with albuterol when compared with subjects who were not pretreated. Although additional, prospective studies are warranted, we conclude that <em>β</em>-agonist pretreatment of experimental subjects does not alter many aspects of the inflammatory response produced by SAC.</p></div>","PeriodicalId":74618,"journal":{"name":"Pulmonary pharmacology","volume":"8 6","pages":"Pages 237-243"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/pulp.1995.1032","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19788414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Masaki Fujimura, Yasuto Nakatsumi , Kouichi Nishi , Kazuo Kasahara , Tamotsu Matsuda , Kanazawa Asthma Research Group
{"title":"Involvement of thromboxane A2 in bronchial hyperresponsiveness of asthma","authors":"Masaki Fujimura, Yasuto Nakatsumi , Kouichi Nishi , Kazuo Kasahara , Tamotsu Matsuda , Kanazawa Asthma Research Group","doi":"10.1006/pulp.1995.1034","DOIUrl":"10.1006/pulp.1995.1034","url":null,"abstract":"<div><p>It has been considered that thromboxane A<sub>2</sub> (TXA<sub>2</sub>) is involved in the development of bronchial hyperresponsiveness (BHR), a characteristic feature of asthma. To ensure the involvement of TXA<sub>2</sub> in BHR of asthma, effects of a 1-week treatment with two orally active TXA<sub>2</sub> antagonists, BAY u 3405 and S-1452, on BHR were examined in 10 and 13 patients with stable asthma, respectively, in two consecutive double-blinded, randomized, placebo-controlled, two-phase crossover studies. Provocative concentration of methacholine causing a 20% fall in FEV, (PC<sub>20</sub>-FEV<sub>1</sub>) with BAY u 3405 (0.78 (GSEM, 1.50) mg/ml) was significantly greater than the value with placebo (0.65 (GSEM, 1.46) mg/ml) (ratio 1.23 times, 95% CI 1.01 to 1.46: <em>P</em>=0.0401). PC<sub>20</sub>-FEV<sub>1</sub> was also significantly increased with S-1452 (0.43 (GSEM, 1.39) mg/ml) compared with placebo (0.29 (GSEM, 1.27) mg/ml) (ratio 1.75 times, 95% CI 1.05 to 2.45: <em>P</em>=0.0189). Baseline pulmonary function was not altered by these treatments. These results may ensure that TXA<sub>2</sub> is significantly involved in the BHR of asthma while the degree of contribution may be small.</p></div>","PeriodicalId":74618,"journal":{"name":"Pulmonary pharmacology","volume":"8 6","pages":"Pages 251-257"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/pulp.1995.1034","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19788416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Effects of Nedocromil Sodium and Sodium Cromoglycate on Airway Nerves and Neurogenic Responses in Asthma","authors":"A.A. Norris","doi":"10.1006/pulp.1995.1030","DOIUrl":"10.1006/pulp.1995.1030","url":null,"abstract":"","PeriodicalId":74618,"journal":{"name":"Pulmonary pharmacology","volume":"8 4","pages":"Pages 227-230"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/pulp.1995.1030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19754607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Role of Sensory Neuropeptides in Airway Hyperresponsiveness","authors":"J.N. Baraniuk","doi":"10.1006/pulp.1995.1026","DOIUrl":"10.1006/pulp.1995.1026","url":null,"abstract":"","PeriodicalId":74618,"journal":{"name":"Pulmonary pharmacology","volume":"8 4","pages":"Pages 195-202"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/pulp.1995.1026","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19754600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mechanisms and Modulation of Capsaicin Activity on Airway Afferent Nerves","authors":"A.J. Fox","doi":"10.1006/pulp.1995.1028","DOIUrl":"10.1006/pulp.1995.1028","url":null,"abstract":"","PeriodicalId":74618,"journal":{"name":"Pulmonary pharmacology","volume":"8 4","pages":"Pages 207-215"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/pulp.1995.1028","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19754604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Overview of Neural Mechanisms in Asthma","authors":"P.J. Barnes","doi":"10.1006/pulp.1995.1020","DOIUrl":"10.1006/pulp.1995.1020","url":null,"abstract":"<div><p>Summary: There is much evidence that neural mechanisms are involved in the mechanisms and symptoms of asthma. Afferent nerves may be activated and sensitized by inflammatory mechanisms, resulting in symptoms such us cough and chest tightness, in activation of cholinergic reflexes and in the release of inflammatory neuropeptides. Cholinergic mechanisms are the predominant bronchoconstrictor neural pathway and may be enhanced in asthma, particularly during exacerbations, through several mechanisms, including impaired function of muscarinic autoreceptors on cholinergic nerve terminals. There may also be abnormalities in adrenergic control and in the function of β-adrenoceptors, particularly in severe asthma. The neurotransmitter of bronchodilator nerves is now identified as nitric oxide and this mechanism may be impaired during asthma exacerbations. Finally, neurogenic inflammation, due to release of neuropeptides from sensory nerves, may contribute and amplify the inflammation in asthmatic airways.</p></div>","PeriodicalId":74618,"journal":{"name":"Pulmonary pharmacology","volume":"8 4","pages":"Pages 151-159"},"PeriodicalIF":0.0,"publicationDate":"1995-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1006/pulp.1995.1020","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19754595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}