dinoprost and Wounds--Stab

We report here that 4-dibenzo[a,d]cyclohepten-5-ylidene-1-[4-(2H-tetrazol-5-yl)-butyl]-piperidine (AT-56) is an orally active and selective inhibitor of lipocalin-type prostaglandin (PG) D synthase (L-PGDS). AT-56 inhibited human and mouse L-PGDSs in a concentration (3-250 microm)-dependent manner but did not affect the activities of hematopoietic PGD synthase (H-PGDS), cyclooxygenase-1 and -2, and microsomal PGE synthase-1. AT-56 inhibited the L-PGDS activity in a competitive manner against the substrate PGH(2) (K(m) = 14 microm) with a K(i) value of 75 microm but did not inhibit the binding of 13-cis-retinoic acid, a nonsubstrate lipophilic ligand, to L-PGDS. NMR titration analysis revealed that AT-56 occupied the catalytic pocket, but not the retinoid-binding pocket, of L-PGDS. AT-56 inhibited the production of PGD(2) by L-PGDS-expressing human TE-671 cells after stimulation with Ca(2+) ionophore (5 microm A23187) with an IC(50) value of about 3 microm without affecting their production of PGE(2) and PGF(2alpha) but had no effect on the PGD(2) production by H-PGDS-expressing human megakaryocytes. Orally administered AT-56 (<30 mg/kg body weight) decreased the PGD(2) production to 40% in the brain of H-PGDS-deficient mice after a stab wound injury in a dose-dependent manner without affecting the production of PGE(2) and PGF(2alpha) and also suppressed the accumulation of eosinophils and monocytes in the bronco-alveolar lavage fluid from the antigen-induced lung inflammation model of human L-PGDS-transgenic mice.

Topics: Administration, Oral; Animals; Calcimycin; Cyclooxygenase 1; Cyclooxygenase 2; Dinoprost; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Evaluation, Preclinical; Enzyme Inhibitors; Eosinophils; Humans; Intramolecular Oxidoreductases; Ionophores; Lipocalins; Male; Megakaryocytes; Membrane Proteins; Mice; Mice, Knockout; Monocytes; Pneumonia; Prostaglandin D2; Wound Healing; Wounds, Stab

A radioimmunological method is presented for the determination of the quantity of prostaglandin F2 alpha in cut wounds on the skin of guinea pigs. Rapidly increasing quantities of prostaglandin F2 alpha can be found in skin cuts, and the level reaches 71 ng/g within the 1st hour after the injury. In the postmortem period, the quantities calculated in the cuts while the animals were still alive gradually decreased and reached a value of 17 ng/g in the 6th h after death. In postmortem cuts, inflicted in the 8th h after death, the prostaglandin was 14-18 ng/g. In later postmortem cuts the quantity was about 9-10 ng/g. Establishing the dynamics of the quantitative changes permits investigation of the prostaglandin to be used to certify whether the victim was alive or not, as well as when the skin damage was inflicted.

Topics: Animals; Dinoprost; Guinea Pigs; Prostaglandins F; Skin; Wound Healing; Wounds, Stab