The effects of Bronchodilators in common clinical use were studied by examining the cyclic AMP content in the tracheas of guinea pigs, similar in tracheobronchial sensitivity to bronchial asthma patients, and rats, similar to normal subjects, after intraperitoneal injection, using a radioimmunoassay technique with [³H]-labelled cyclic AMP.
A) The effects of agents on the cyclic AMP content in the guinea pig trachea:
1) Ten minutes after administion of 0.5mg/kg Isoproteronol, a stimulant, or 50mg/kg Aminophylline, a xanthine conductor, the cyclic AMP content increased 2-3 times, and the two agents in combination revealed an additive tendency. When 2mg/kg of Propranolol, an adrenergic blocking agent was administered, the effect of Isoproterenol was cut in half.
2) In ten minutes, 2mg/kg Histamine increased the cyclic AMP content by 260% and when Isoproterenol was administered, it did not alter the effect of the Histamine. On the other hand, the effect of Histamine wa reduced to 1/5 by 2mg/kg of the antihistamine Diphenhydramine, but not by Propranolol.
3) The cycic AMP was doubled in 10 minutes by a 1mg/kg dose of Prednisolone, glucocorticosteroid, while 5mg/kg increased the initial value 5 times. In combination with 2mg/kg Isoproterenol or 5mg/kg Aminophylline, the additive increase was significantly higer than that produced by either agent alone. However, in combination with 2mg/kg of Imidazole, a phosphodiesterase inhibitor, and 2mg/kg Propranolol, the effect of Prednisolone was decreased by 1/3-2/3.
4) Concerning the time factor, 1mg/kg Isoproterenol peaked at 10min., declining to 50% of the peak value after 60min, thereafter further declining rapidly and reaching the initial level at 240 minutes. In the case of 1mg/kg Metaproterenol, 0.5mg/kg Salbutamol, 0.5mg/kg Clorprenaline, and 0.1mg/kg Terbutaline, the peak level was attained after 10min., and no significant change was noted after 240min., declining gradually to the initial level after 360 minutes. While 0.3mg/kg Trimetoquinol peaked at the same time, it then gradually declined.
5) Timewise the effect of 50mg/kg Aminophylline was similar to that of Metaproternol, while 1mg/kg Prednisolone reached its peak at 60min., and was still significantly higher than the initial value at 360 minutes.
B) Effects of agents on the cyclic AMP content in the rat trachea:
1) 10min. administration of 1mg/kg, 1mg/kg Metaproterenol, 50mg/kg Aminophylline or 1mg/kg Prednisolone, cyclic AMP content increased by 1.5 to 2.5 times, but the increase was only 30%-50% that of the guinea pigs. The time curve of these agents was similar in pattern to that of the guinea pig experiment, but the effects did not last so long.
2) Based on the above data, we suggest that the threshold of response in the rat tracheal muscle was higher than that of the guinea pig.

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Angiotensin I (AI) is a decapeptide generated in blood by the action of renin upon an α₂-globulin in plasma. It is well known that AI is cnoverted to the octapeptide, angiotensin II (AII) within a single passage through the pulmonary circulation. But its conversion rate varied from 10% to 80% according to the papers issued by the different authors. Male guinea-pigs weighing 250-300g were killed. The lungs were removed, suspended in a glass chamber and perfused by a constant output pump at 10ml/min via the pulmonary vein with Krebs-Hensleit solution containing 5% dextran at 37°C saturated with oxygen and carbon dioxide (95:5, v/v). For the detection of AI and AII the effluent from the lungs was superf used over assay tissues, these were rat colons. Contractions of rat colons were detected by an isotonic transducer (ME Commercial, Tokyo, Japan) and displayed on a polyrecorder.A dose of AI and AII was infused into the pulmonary vein or over assues directly.
The method for the calculation of % activation of AI is as follows;
% activation=AI(l)-AI(c)/AII(c)-AI(c)×100
AI(c): response of AI infused directly on assay tissues
AI(I): response of Al infused into the pulmonary vein
AII(c): response of AII infused into the pulmonary vein
1) The percent activation of AI became bigger with increasing its dose, and it showed the maximum percent activation (87.04±7.59%) at the dose of 100ng/ml. Then the percent activation of Al decreased with increasing doses.
2) The average percent activation of AI was 86.17±8.06% without indomethacin, and13.03±6.98% with indomethacin (p<0.001).

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A case of hypersensitivity pneumonitis which was considered to be caused by inhalation of budgerigar droppings was reported.
A positive skin reaction to the antigen of dropping extracts was observed 3 hours after injection and reached a maximum in 24 hours with ulceration.
The inhalation of budgerigar dropping extracts caused decreases in the VC an. FEV_1.0 of the patient and an increase in temperature after 6 hours.
In a study of antibodies in the patient's serum, a precipitin band between the serum and dropping extracts or budgerigar serum was detected. However, in healthy persons, there was negative skin reaction and no precipitin band was observed.
After corticosteroid therapy, clinical symptoms and findings such as dyspnea, cough, abnormal shadows on the chest X-ray disappeared, and the precipitin band was not detected.
These results suggested that frequent inhalation of budgerigar droppings caused the hypersensitivity pneumonitis in this patient.

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A 20-year-old woman has been noted to have an abnormal shadow protruding from the right superior mediastinum since the age of twelve. On account of recent enlargement of the shadow, though no symptom appeared, the tumor was extirpated and diagnosed as cavernous lymphangioma of the mediastinum.

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