Bronchial Reactivity to Prostaglandins F_2α, E₂, and Histamine in Different Types of Asthma

Abstract

Bronchial reactivity to prostaglandins F_2α (PGF_2α), E₂ (PGE2) and histamine has been studied in 27 patients with aspirin-sensitive asthma and in 28 asthmatics without this sensitivity. Of the latter group, 13 patients had atopic, 9 infectious, and 6 mixed type of asthma. Atopic patients were characterized by vivid reactivity to low doses of both PGF_2α and histamine. In patients with infectious asthma significantly higher doses of both PGF_2α and histamine were necessary to induce bronchoconstriction as compared to atopies. Aspirin-sensitive patients responded quickly with bronchial spasm to similar doses of histamine as atopies, but tolerated significantly higher doses of PGF_2α. There was no difference in reactivity to PGF_2α between patients with aspirin sensitivity and those with infectious asthma. 5 and 10 min after administration of 60 μg PGE₂ significantly better improvement in ventilation occurred in aspirin-sensitive patients than in those of either atopic or infectious groups. The results obtained point to differences in bronchial reactivity to prostaglandins and histamine depending on type of asthma and severity of its symptoms.

Heterogeneity of Bronchial Asthma

“…Demonstration of hyperreactivity of the bronchial tissues is almost obligatory for the diagnosis of bronchial asthma (1,3,7,27,40,50,58). Hyperreactivity is demonstrated not only to histamine and acetylcholine, but to other biochemical agents as well, including bradykinin, SRS-A and prostaglandin F2-alpha (1,35,55,58). By means of bronchial provocation testing, differentiation can be made with respect to the degree of sensitivity to these trigger agents.…”

“…It is possible to demonstrate a marked disparity in response between different trigger stimuli, be it between histamine and metacholine/-acetylcholine (26,28,53), or between histamine and prostaglandin F2-alpha (35,55). Histamine may act directly on the smooth muscles in the bronchi as well as be a trigger for parasympathetic irritant receptors in the bronchi.…”

“…Szczeklik and coworkers investigated bronchial reactivity to prostaglandins F2-alpha, E2 and histamine, in 55 patients with asthma (55). The patients were divided into two distinct subgroups.…”

“…There are, however, only three models which are suited for objective investigations in this respect, namely induction of asthma by inhalation of relevant biochemical agents, bronchial provocation tests with allergens, and physical exercise workload tests (2,13,20,21,27,28,35,52,53,55,57,58). Many variables may affect the results of such studies (2,7,20).…”

Aspirin sensitive asthma

“…In contrast Szczeklik et al investigated airway response to PGF21 in three groups of asthmatic subjects, namely aspirin-sensitive, atopic and intrinsic respectively. Atopic patients were reactive to low doses of histamine and PGF2a [30]. Aspirin-sensitive asthmatics had similar airway responses to histamine but tolerated higher doses of PGF2a.…”