Hars B
Laboratoire de Neurobiologie de l'Apprentissage et de la Mémoire, URA CNRS 1491, Universté Paris-sud, Bât. 445, 91405 Orsay Cedex, France.
Brain Res. 1999 Jan 16;816(1):209-19. doi: 10.1016/s0006-8993(98)01183-4.
Pontine cholinergic structures are known to play a key role in the regulation of vigilance states associated with desynchronised EEG, i. e., wakefulness and paradoxical sleep. As the cholinergic cells of these nuclei, the pedunculopontine tegmentum (PPT) and the laterodorsal tegmentum, are enriched with nitric oxide synthase (NOS), we tested the hypothesis that nitric oxide (NO) in the pons is implicated in wake and sleep regulation. For this reason, a NOS inhibitor, a NO precursor and a NO donor were injected in the PPT of rats. Vigilance states were recorded for 6 h following the injections. Quantification of vigilance states after drug injections were compared to those obtained in control conditions. It appeared that the NO donor had a slight effect on vigilance states, but the NOS inhibitor decreased sleep and inversely the NO precursor increased sleep. These results show for the first time in the rat that a NOS inhibitor, injected directly into the PPT, is able to reduce sleep and that a NO precursor had the opposite effect. They suggest that endogenous NO production in the PPT has a somnogenic effect. The participation of endogenous NO in vigilance regulation is discussed in light of the role attributed to pontine cholinergic system in wakefulness and sleep.
已知脑桥胆碱能结构在与脑电图去同步化相关的警觉状态调节中起关键作用，即清醒和异相睡眠。由于这些核团（脚桥被盖核和外侧背盖核）的胆碱能细胞富含一氧化氮合酶（NOS），我们测试了脑桥中的一氧化氮（NO）参与清醒和睡眠调节的假说。因此，将一种NOS抑制剂、一种NO前体和一种NO供体注射到大鼠的脚桥被盖核中。注射后记录6小时的警觉状态。将药物注射后警觉状态的量化结果与在对照条件下获得的结果进行比较。结果显示，NO供体对警觉状态有轻微影响，但NOS抑制剂减少了睡眠，相反，NO前体增加了睡眠。这些结果首次在大鼠中表明，直接注射到脚桥被盖核中的NOS抑制剂能够减少睡眠，而NO前体则有相反的作用。它们表明脚桥被盖核中内源性NO的产生具有促睡眠作用。根据脑桥胆碱能系统在清醒和睡眠中所起的作用，对内源性NO在警觉调节中的参与进行了讨论。
