Inhibition of hind-paw edema and cutaneous vascular plasma extravasation by 2-chloro-3-methoxycarbonylpropionamido-1,4-naphthoquinone (PP1D1) in mice.

2-Chloro-3-methoxycarbonylpropionamido-1,4-naphthoquinone (PP1D1) produced a dose-dependent inhibition of the polymyxin B-induced hind-paw edema in normal as well as in adrenalectomized mice. A comparable inhibitory profile was observed in mice to which PP1D1 was injected i.p. or applied orally. Unlike dexamethasone, PP1D1 had no effect on the liver glycogen content in fasting adrenalectomized mice. Ear edema caused by passive cutaneous anaphylactic reaction, or by subcutaneous injection of compound 48/80, histamine, serotonin, bradykinin or substance P was reduced by PP1D1 in a dose-dependent manner. In addition, topical application of PP1D1 suppressed the capsaicin- and arachidonic acid-induced ear edema. In compound 48/80-pretreated mice, the tissue histamine content was greatly reduced. Under these conditions, PP1D1 reduced the bradykinin- and substance P-induced ear edema to a significantly greater extent than diphenhydramine plus methysergide. These results suggest that the inhibitory effect of PP1D1 on the edematous response is due to the protection of the microvasculature from mediator challenge.