“The … of PGD2 in response … topically applied methylnicotinate occurred in a dose-dependent manner over the concentration range of 10(-3) to 10(-1) M. The release of PGD2 was not accompanied by a release of histamine, suggesting that the release of PGD2 was not from the mast cell.”
“Topical … methylnicotinate (10(-1) M) to the forearms of human volunteers … in 58- to 122-times increases in levels of PGD2 and 25- to 33-times increases in levels of the metabolite of PGD2, 9 …,11 beta-PGF2, in blood drawn from the antecubital vein draining the treated sites.”