Strain-Related Differences in the Tracheal Responsiveness of Sensitized Guinea Pig

Abstract

The purpose of this study was to evaluate the strain-related differences in tracheal hyperresponsiveness in control and egg albumen-sensitized guinea pigs. Concentration-response curves to acetylcholine and barium chloride were established from tracheal rings of Dunkin-Hartley and BEA strain guinea pigs. In the Dunkin-Hartley strain, sensitization did not signficantly increase the tracheal responsiveness to acetylcholine and barium chloride. By contrast, in the BFA strain, significant sensitization-induced hyperreactivity was achieved as the maximal contractions induced by acetylcholine and barium chloride, were enhanced from 6.5 ± 1.2 and 3.2 ± 0.4 mN in control to 10.0 ± 1.4 and 5.6 ± 0.8 mN, respectively, in sensitized animals. However, antigen challenge, performed in vitro, exhibited a similar amplitude of contraction in tracheal rings from both strains (Dunkin-Hartley 5.1+0.8 mN; BFA 5.9 ± 0.5 mN). Finally, while the two guinea-pig strains developed specific sensitization to allergen, only tracheal rings from the BFA strain developed hyperresponsiveness to acetylcholine and barium chloride. The strain-related difference appears to be partly explained by a lower basal reactivity in the BFA strain both to acetylcholine (E_m 7.3 ± 1.7 and 6.5 ± 1.2 mN for Dunkin-Hartley and BFA, respectively) and barium chloride (E_m 9.4 ± 2.6 and 3.2 ± 0.4 mN for Dunkin-Hartley and BFA, respectively). As the same procedure of sensitization provides different results in the genesis of hyperreactivity between the two guinea-pig strains used for asthma models, the BFA guinea-pig strain seems to be a better model because sensitized non-challenged animals could easily be dissociated from control ones, similar to that which occurs in asthmatic patients during provocation tests with cholinergic drugs.

Effect of guinea‐pig purified immunoglobulin G1 on the responsiveness of tracheal, aortic, vas deferens and ileum smooth muscles

“…We recently reported that the active sensitization of ileum and aorta [7]. Consequently, a common defect may guinea-pigs in vivo to egg albumen led to contractile occttr after sensitization in these dilTerent rnuscles, hyperresponsiveness in various muscles [1,2]. hi this…”

Effect of temperature reduction on the vas deferens hyperresponsiveness of sensitized mice

“…Although the pathophysiological changes associated with antigen sensitization have not yet been clearly defined, a non-specific hyperresponsiveness is a characteristic feature that has been primarily detected in airways (Boushey, Holtzman, Sheller & Nadel, 1980). Until now, smooth muscle hyperresponsiveness occurring in allergic diseases and sensitized models has been mainly investigated in airways with special attention to the asthmatic disease (Saad & Burka, 1983;Morcillo, Perpina & Esplugues, 1984;Mansour & Daniel, 1987;Featherstone, Hutson, Holgate & Church, 1988;Kamm & Drazen, 1992;Bidon, Blin, Gogny, Vu & Jondet, 1995). We recently reported a lack of specificity in target organs for smooth muscle hyperreactivity that occurred in both vas deferens and ileum isolated from ovalbumen actively sensitized guinea-pigs (Bidon, Blin, Gogny, Vu & Jondet, 1994).…”

“…Recently, Pascual et al (1993) showed that aortic rings became hyperreactive in a sensitized guinea-pig model. Sensitized smooth muscle has been shown to undergo non-specific alterations in mechanical properties, occurring prior to the specific antigen challenge (Morcillo et al, 1984;Ortiz et al, 1989Bidon et al, 1994Bidon et al, , 1995. This suggested that the essential defect in allergic hyperresponsiveness might be at the muscle cell level.…”