[The effect of verapamil on adrenocortical hormone secretion].
Variations in circadian cortisol rhythm, morning ACTH concentration and the 24-hour cortisol excretion were examined in 15 healthy volunteers and 9 untreated patients with cardiovascular diseases. These variations were measured under basal conditions and during low dose (ACTHL-test) and also a high dose (ACTHH-test) ACTH stimulation. Additionally, in the patients with cardiovascular diseases the effect of verapamil-administration was investigated. Under basal conditions no significant differences were to be seen between normal subjects and the patients, either before or after therapy. The two functional tests resulted in almost identical increases of cortisol and ACTH levels, both in healthy subjects and the patients before verapamil. It was found that after verapamil application during the ACTHL-test, the levels of plasma cortisol decreased in comparison with the values noted before verapamil (p less than 0.05). However, in the ACTHH-test a significant increase of the plasma cortisol (p less than 0.05) was evident. Our results lead to the conclusion that after verapamil therapy, under slight loading, the plasma cortisol concentration can be expected to decrease slightly, and in extremely high stress situations it will increase.