Adachi T, Shinomura T, Nakao S, Kurata J, Murakawa M, Shichino T, Seo N, Mori K
Department of Anesthesia, Kyoto University Hospital, Japan.
Anesth Analg. 1995 Oct;81(4):862-5. doi: 10.1097/00000539-199510000-00035.
We previously found that acute administration of a nitric oxide synthase (NOS) inhibitor (N omega-nitro-L-arginine methyl ester [L-NAME]) does not reduce the minimum alveolar anesthetic concentration (MAC) of halothane in rats. However, a recent study has suggested that brain NOS activity could not be inhibited by more than approximately 50% by acute administration of L-NAME. To investigate the effect of marked inhibition of NOS activity on the MAC of halothane, we measured cerebellar NOS activity, cerebellar cyclic guanosine monophosphate (cGMP) levels, and halothane MAC in rats chronically treated with L-NAME and compared the results to those of the saline-treated control group. Although the cerebellar NOS activity and cGMP levels were significantly decreased (14% and 2.7% of control, respectively) by L-NAME, the value of the halothane MAC was not significantly affected. These results suggest that the anesthetic action of halothane, as measured by its MAC in rats, is not related to NOS activity or cGMP levels in the brain.
我们之前发现，急性给予一氧化氮合酶（NOS）抑制剂（Nω-硝基-L-精氨酸甲酯 [L-NAME]）并不会降低大鼠体内氟烷的最低肺泡有效浓度（MAC）。然而，最近一项研究表明，急性给予L-NAME对脑NOS活性的抑制作用不会超过约50%。为了研究显著抑制NOS活性对氟烷MAC的影响，我们测量了长期接受L-NAME治疗的大鼠的小脑NOS活性、小脑环磷酸鸟苷（cGMP）水平以及氟烷MAC，并将结果与生理盐水处理的对照组进行比较。尽管L-NAME使小脑NOS活性和cGMP水平显著降低（分别为对照组的14%和2.7%），但氟烷MAC的值并未受到显著影响。这些结果表明，以大鼠MAC衡量的氟烷麻醉作用与脑中的NOS活性或cGMP水平无关。
