SYOSAIKO-TO AND SAIBOKU-TO (CHINESE-JAPANESE HERBAL MEDICINE) SUPPRESS THE RELEASE OF ARACHIDONIC-ACID METABOLITES FROM CULTURED PORCINE PULMONARY-ARTERY ENDOTHELIAL-CELLS

The influences of Syosaiko-to and Saiboku-to, traditional Chinese-Japa nese medicines, on the arachidonic acid metabolism of porcine pulmonar y artery endothelial cells (PPAEC) in culture were investigated. 6-ket o-PGF(1 alpha) a stable end product of prostacyclin, released by PPAEC during a 48 h incubation period with 1000 mu g/ml of Syosaiko-to or S aiboku-to was significantly decreased. Analysis of the eicosanoid prof ile by high performance liquid chromatography revealed that both cyclo oxygenase and lipoxygenase derivatives were released in smaller than u sual proportions from PPAEC during 24 h incubation periods with 500 mu g/ml of Syosaiko-to or Saiboku-to. Clinically, Syosaiko-to is used fo r chronic hepatitis and Saiboku-to is prescribed for bronchial asthma. The experimental findings could explain the anti-inflammatory effect of Syosaiko-to and Saiboku-to from the perspective of their influences on arachidonic acid metabolic activity associated with PPAEC.