Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Comparison of the protective effect of intravenous urodilatin (URO) or ANP against an acetylcholine(ACh)-induced bronchoconstriction in the rat in vivo


European Respiratory Journal 4 (1991), Suppl. 14, S.606s-607s
ISSN: 0903-1936
ISSN: 1399-3003
Fraunhofer ITA ( ITEM) ()
Acetylcholine; lung; rat

Inhaled ANP inhibits histamine induced bronchoconstriction in man (1). We compared the protective effect of equimolar doses of intravenous ANP or URO against a bronchoconstriction induced by ACh-inhalation in 46 anaesthetized intubated spontaneously breathing Wistar rats. The animals received an intravenous infusion of 0.5 ml ANP, URO or vehicle (NaCl; control group=C) for 10 min. During the infusion period an ACH-challenge test was started after 5 min. Using whole-bodypethysmography typical spontaneous respiratory function parameters were recorded under steady state conditions before the infusion and before and at the end of the ACh-challenge. Forced parameters (volume-time and flow-volume relation) were measured in hyperventilation-induced apnoe after the ACh-challenge and included e.g. FVC (forced vital capacity), FEV0.1 (forced expiratory volume in 0.1 sec), FEV0.2, PEF (peak expiratory flow), MMEF (maximal mid-expiratory flow), FEF75 (forced expiratory flow at 75 % forced vital ca pacity), FEF50 and FEF25. ACh induced a significant bronchoconstriction without any significant differences between the treatment groups regarding the spontaneous breathing and forced volume-time relation parameters. The more sensitive flow-volume curve, however, showed a significant protective effect of 11.4 and 22.8 pmol/kg/min (40 and 80 ng/kg/min) URO compared to C (p < 0.01: PEF: URO 113.6 +- 9.2/ 114.8 +- 6.9, C: 98.4 +- 5,8 ml/s; MMEF: URO: 77.3 +- 11.4/ 74.9 +- 10.5, C. 56.6 +- 11.3 ml/s; FEF75: URO: 112.2 +- 8.6/ 113.8 +- 7.0, C: 94.9 +- 9,4 ml/s; FEF50: URO: 83.2 +- 11.2/ 82.0 +- 11.6, C: 63.2 +- 10.1 ml/s; p < 0.05: FEF25: URO: 42.4 +- 10.2/ 38.3 +- 8.2, C: 27.7 +- 9.3 ml/s ) while the infusion of ANP was without any significant influence in all three dose groups. Heart rate was controlled byE CG and did not change significantly during the infusion period before and at the end of the ACh-challenge. It is concluded that intravenous URO but not ANP shows a significant protect ive effect against ACh-induced bronchoconstriction in rats in vivo.