桂枝汤对发热及低体温大鼠下丘脑15-羟基前列腺素脱氢酶活性的影响

目的：研究桂枝汤对发热和低体温大鼠下丘脑组织内15-PGDH活性的影响，进一步阐明桂枝汤体温双向调节作用机制。方法：采用核素示踪技术测定酵母性发热和安痛定性低体温大鼠及桂枝汤处理组下丘脑组织内15-PGDH活性，并观察其与体温变化的关系。结果：皮下注射酵母可降低下丘脑15-PGDH活性，桂枝汤灌胃可剂量依赖性地抑制该变化并促进发热大鼠体温的恢复，两者呈正相关；而腹腔注射安痛定后，随着体温下降，15-PGDH活性有升高倾向，桂枝汤可抑制该酶活性并加速体温恢复正常，但两者呈弱相关。结论：大鼠下丘脑内15-PGDH可能参与机体体温调节并可能是桂枝汤解热作用靶点之一，但与其抗低体温作用关联不大。

Effect on Prostaglandin Dehydrogenase in Hypothalamus in Both the Pyretic and Hypothermia Rats by Guizhi Tang

To further highlight Guizhi Tang's mechanism of dual\|directional thermoregulation,the 15\|PGDH activity in pyretic and hypothermia rats was detected using isotopic tracing assay.A decrease in PGDH activity paralleled with a pronounced rise in body temperature in rat hypothalamus 5.5hr after a s.c. yeast\|injection was observed and both the responses was counteracted by the treatment of Guizhi Tang orally in a dose\|dependent manner.Aminopyrine induced a tendency to enhance PGDH activity and a marked drop in body temperature meanwhile in rats 1 hr later,but there was a poor relation between changes in body temperature and in activity of PGDH evoked by Guizhi Tang.Present data suggest that PGDH in hypothalamus may play a role in thermoregulation in rats and is also a target of antipyretic action of Guizhi Tang,but it probably does not contribute to anti\|hypothermia action of Guizhi Tang.