Influence of the specific antagonist of PAF-acether, BN 52021, and of Ginkgo extract on the rejection of murine tail skin allografts and the PAF-acether mortality in mice in particular consideration of the role of TXB2.
An oral application of 2 x 10 mg/kg daily of the PAF antagonist, BN 52021, significantly prolonged the distal allograft survival in the murine tail skin model of cell-mediated allograft rejection. BN 52021 diminished the TXB2 content in the skin at and near to the transplantation site by two thirds whereas PAF-acether significantly enhanced the TXB2 content in murine tail skin. Similar to the tail skin BN 52021 also reduced by more than 70% the TXB2 release from human granulocytes stimulated by calcium ionophore A 23187. The PAF-acether mortality (LD75) in NMRI mice was decreased to 20% by BN 52021 with a lower dose than by BN 52020. Comparing Ginkgo total extract in doses which significantly diminished the 75% mortality by PAF-acether in mice with BN 52021 and BN 52020 in doses that produced the same inhibitory effect, a potentiated effect of Ginkgo extract resulted with respect to the share of BN 52021 and BN 52020 in Ginkgo extract.
Becker
K
K
Department of Pharmacology and Toxicology, Martin Luther University, Halle-Wittenberg, GDR.
Braquet
P
P
Förster
W
W
D000818:Animals; D004224:Diterpenes; D046934:Ginkgolides; D006084:Graft Rejection / Q000187:drug effects*; D007783:Lactones / Q000494:pharmacology*; D051379:Mice; D010936:Plant Extracts / Q000494:pharmacology; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D012016:Reference Values; D012038:Regeneration / Q000187:drug effects; D012867:Skin / Q000187:drug effects / Q000378:metabolism; D016038:Skin Transplantation; D013929:Thromboxane B2 / Q000502:physiology*; D014184:Transplantation, Homologous
D004224:Diterpenes; D046934:Ginkgolides; D007783:Lactones; D010936:Plant Extracts; D010972:Platelet Activating Factor; D013929:Thromboxane B2; C045856:ginkgolide B