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== Synonyms ==
*''Thuja orientalis'' L. (1753), *''Platycladus stricta'' Spach (1841), *''Biota orientalis'' (L.) Endl. (1847).
== Vernacular names ==
Furthermore, a labdane-type diterpene, pinusolide was isolated from the hexane and chloroform extracts of the leaves of ''P. orientalis'' . Pinusolide is a potent platelet activating factor (PAF) receptor-binding antagonist, which inhibited PAF-induced aggregation of rabbit platelets (IC<sub>50</sub>value of 5μM), but had no inhibitory effect on ADP-, thrombin-, or collagen-induced platelet aggregation. Pinusolide also protected mice from PAF-induced lethality (ED<sub>50</sub>values of 1.1 mg/kg, intravenous, and 69 mg/kg, per oral). Topical administration of pinusolide, at 2 mg/ear, was effective in inhibiting croton oil-induced mouse ear oedema. Ears of treated mice fully recovered, in contrast to the necrotized ears of their untreated controls.
The effects of pinusolide on PAF-induced [3H]serotonin release from rabbit platelets, hypotension and vascular permeability were furthermore confirmed. Pinusolide (IC<sub>50</sub>, about 5 x 10<sup>-6</sup>M) inhibited specifically [3H]serotonin release from rabbit platelets when stimulated with PAF (5 x 10<sup>-8</sup>M), but showed no effect when induced by ADP, collagen and thrombin. It also inhibited PAF-induced hypotension in a dose-dependent manner in rats with no effect on the hypotension induced by acetylcholine, histamine and serotonin. The inhibitory effect of pinusolide on the PAF-induced vascular permeability is less specific than the induced hypotension. The results suggest that pinusolide may prove of therapeutic value in the treatment of hypotension and a molecular design of pinusolide analogues may provide the possibility of new PAF specific antagonists.
== Description ==
*A large shrub or small to medium-sized tree, rarely exceeding 20 m tall, in cultivation often forming multiple stems; habit dense, usually broadly conical with ascending branches from bare stems; bark thin, reddish-brown, exfoliating in thin longitudinal strips; branches with the foliage held in vertically aligned sprays that always point upwards. *Leaves decussate, scale-like, size correlated with growth of the shoots; leaves on leading shoots continue to elongate until after some years they wither and break up, leaves of finer lateral sprays about 2 mm long, tightly adpressed; foliage pale green, odourless when crushed. *Inflorescence a unisexual cone. Male cones terminal, 2-3 mm long. Female cones oblong, 20-25 mm long, 10-18 mm wide when closed, usually with 6-8 fleshy scales, with a deeply recurved horn below the tip of each scale. Scales glaucous when growing, maturing and ripening to bright brown before opening; lower 4 scales fertile with 2(-3) seeds. *Seed ovate, wingless, 5-7 mm long, 3-4 mm in diameter.
== Growth and development ==
== Other botanical information ==
''P. orientalis'' belongs to a monotypic genus closely related to ''Thuja'' . It can be easily distinguished by the vertical arrangement of its sprays of foliage, which lack odour when crushed, the strongly hooked bract tips of the cone scales and its wingless seeds. Numerous cultivars are registered in horticultural trade, ranging from dwarf forms to small trees; some with juvenile needle-like leaves, others green golden, slightly variegated or with filamentous branches.
== Ecology ==
== Literature ==
* Chen, C.P., Lin, C.C. & Namba, T., 1987. Development of natural crude drug resources from Taiwan VI. In-vitro studies of the inhibitory effect of 12 microorganisms. Shoyakugaku Zasshi 41(3): 215-225.