I Intradermal injection of prostaglandin (PG) D1 and D2 in the human forearm produced a longlasting dose-related erythema. When compared with prostaglandin E1 or E2 the order of potency for erythema production was PGE1 > PGE2 > PGD2 > PGD1. 2 In rat skin, prostaglandin D2 but not D1 caused an increase in vascular permeability as quantitated by the Evans blue method and the 251I-albumin extravasation technique. Prostaglandin E2 was 3-5 times more potent than prostaglandin D2. 3 Prostaglandin D2 (10 ng) potentiated the increase in vascular permeability in rat skin produced by histamine, but not that produced by bradykinin. 4 Prostaglandin D2 (10, 20 and 50 ng) did not elicit oedema or hyperalgesia in the rat paw oedema test, but potentiated carrageenan-induced oedema; hyperalgesia was potentiated by doses of 100 ng and above.
Bronchoalveolar lavage (BAL) was performed on 28 asthma patients, 7 patients with emphysema and 11 control subjects. Total and differential cell counts were performed and cellular metabolic activity was assessed using luminol and lucigenin amplified chemiluminescence. BAL supernatants were assayed for platelet-activating factor (PAF) and lyso-PAF using a sensitive guinea-pig bioassay. Eight of the asthma patients but none of the emphysema patients or control subjects had PAF in their BAL fluid. Lyso-PAF was measurable in BAL fluid in most subjects and no differences were detected between groups. Among the asthma patients, the presence of PAF in BAL supernatant was significantly associated with a combination of low neutrophil and high lymphocyte counts (p less than 0.05) and with macrophage metabolic activity as assessed by lucigenin chemiluminescence (p less than 0.05).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.