[A new method for assaying anti-inflammatory drugs. Quantitative analysis of pigment leakage into skin by Chromatoscanner CS-900 (author's transl)].
Although the pigment leakage method is one of the most conventional for determining vascular permeability, accuracy in macroscopic measurement of the diameter of the stained area with an arbitary scale leaves much to be desired. We developed a simple and beneficial method for quantitative assay using a densitometer (Chromatoscanner CS-900). Guinea pigs weighing 300 approximately 350 g were used. Formalin as a phlogistic, in a dose of 2.3 approximately 37 mg was injected intradermally in the shaved skin of the back, and 15 mg/kg of pontamine blue was then given into the femoral vein. One hour after the injection the animals were sacrificed and the skin of the back, which was stained by the leaked pigment, was stripped off and allowed to adhere to a wooden plate for 24 hours. Reflection and a zig-zag scanning technique were used to measure the volume of the leaked pigment. There was a liner relationship between the dose of formalin and the integrated values. A dose-dependent relationship was also obtained when histamine, serotonin, kallikrein and bradykinin were used as phlogistics. Representative anti-inflammatory drugs such as aspirin, hydrocortisone, oxyphenbutazone, benzydamine, diclofenac sodium, sodium salicylate and aminopyrine depressed the leakage due to formalin. Depression of leakage by aspirin in a dose of 400 mg/kg was the most remarkable. Pigment leakage elicited by histamine, serotonin, kallikrein and bradykinin was examined on the same individual animal. Aspirin more than the other agents depressed the leakages due to bradykinin and kallikrein. Hydrocortisone and oxyphenbutazone depressed the leakage due to bradykinin, serotonin and histamine, but enhanced that due to kallikrein. The results obtained were consistent with those of a previous study and as this method is simple and more reliable, it is applicable for assay of anti-inflammatory compounds.