Studies on Experimental Asthma Changes of Histamine and Acetylcholine Sensitivity by Sensitization, Serial Water Baths, and Seasons

Abstract

Studies on experimental asthma have been carried out by various methods. The author used a modified Friebel's device, in which guinea pigs were kept and could breathe in natural posture.
Dyspnea was produced by inhalation of nebulized Histamine, Acetylcholine, and Serotonine solutions or Horse-scrum.
Degree of dyspnea was estimated dirided into 5 grades by respiration curves.
Adequate drugs and their optimal concentrations to produce moderate dyspnea suitable for the experiment were investigated and determined, namely 0.5-1.0mg/ml of Histamine or 2.0mg/ml of Acetylcholine was inhaled for 3-5 minuter (0.1-0.3ml) in summer, 1.0-1.5mg/ml and 2.5-3.0mg/ml respectively in winter.
Investigations were preformed not only with bronchial response but also with skin reaction. There were no significant correlation between them.
The author proved that animals sensitized with .Horse-serum manifested an increased sensitivity both in Histamine skin test and Acetylcholine inhalation test.
It was found also that serial daily cold baths (20°C) lowered Histamine sensitivity in a week, but little change was noted by warm baths (40°C).
After 2 weeks the sensitivity was elevated in both cases and in 3-4 weeks it was decreased.
Acetylcholine sensitivity decreased in 2 weeks in warm harm bath group.
Both bronchial and cutaneous sensitivity to Histamine and Acetylcholine fell in winter (December, January and February) and rose in summer (June, July and August).
Therefore bronchial and cutaneous sensitivity to Histamine and Acetylcholine, chemical mediators of allergic reaction, changer various postnatal conditions.