Analgesic and Anti-Inflammatory Effects of Orally Given Streptokinase

According to Lewis(1), the nonapeptide bradykinin is an important mediator of the acute inflammatory reaction. It is, therefore, of interest that orally given proteases were recently shown to antagonize 3 pharmacologic actions of bradykinin: vasodilatation, vascular permeability and smooth muscle contraction(2). The objects of the present investigation were: first, to assess the action of orally given streptokinase against the fourth pharmacologic action of bradykinin, namely, pain production; and second, to appraise the anti-inflammatory action of orally given streptokinase in a controlled animal and clinical experiment.

Methods. 1. Analgesia study. The cantharidin blister technic of Armstrong et al. (3) was slightly modified. This study comprised 30 apparently healthy students and technicians. A band-aid containing 2 drops of tincture cantharidin was applied to the skin of the flexor surface of the forearm the evening before the day of the experiment. When the band-aid was removed the next morning, the area showed a blister with a diameter of about 1.5 to 2 cm. Blisters remained relatively unchanged for 24–48 hours. Intact blisters were opened and the separated epidermis cut away exposing the blister base, which was bathed in Ringer's solution warmed to 37°C. Before the application of bradykinin, the bathing solution was removed and the area dried with filter paper. 0.2 ml bradykinin (0.1 μg) was applied to the dry blister base and the following information recorded:

1. Length of time for pain to develop.

2. Duration of pain.

3. Intensity of pain. This factor was evaluated by each subject on a 1 to 4 + basis.

Ten control subjects received placebo tablets; 10 treated subjects received tablets containing streptokinase 10,000 units; 10 treated subjects received aspirin, 5 grains. Control and experimental groups received one tablet every 15 minutes for one hour following pretreatment control determinations.