Advances in research on the role of nitric oxide in regulating sleep and arousal / 药学学报

Nitric oxide (NO) is widely present in peripheral and central nervous system and regulates many physiological functions. Sleep-arousal is an advanced physiological activity. Studies have shown that NO is involved in the regulation of sleep and arousal. Nitric oxide synthases (NOSs) are a family of enzymes that catalyze the production of NO from L-arginine. Through guanylate cyclase or S-nitrosation of protein, NO can affect the activity of the ascending reticular activating system to regulate the sleep-arousal process. This paper summarizes the production of NO, its effect on sleep-arousal and its mechanism in the ascending reticular activating system, and provides new ideas and directions for the study of sleep and arousal.

Disorders of Consciousness: Practical Management in an Emergency Room

Lowering of the level of consciousness is a very common presentation at the emergency room, often without any history that helps finding an etiology. This emergency requires quick empirical measures to reduce neuronal mortality, with additional protection against sequelae. According to the Advanced Cardiac Life Support (ACLS) guidelines, there are current emergency neurological support protocols, such as the Emergency Neurological Life Support (ENLS) created by the Neurocritical Care Society. The present paper shows how to approach unconscious patients, highlighting possible etiologies and proposed treatments.

The Upper Ascending Reticular Activating System between Intralaminar Thalamic Nuclei and Cerebral Cortex in the Human Brain

PURPOSE: The ascending reticular activating system (ARAS) is responsible for regulation of consciousness. In this study, using diffusion tensor imaging (DTI), we attempted to reconstruct the thalamocortical projections between the intralaminar thalamic nuclei and the frontoparietal cortex in normal subjects. METHODS: DTI data were acquired in 24 healthy subjects and eight kinds of thalamocortical projections were reconstructed: the seed region of interest (ROI) - the intralaminar thalamic nuclei and the eight target ROIs - the medial prefrontal cortex, dorsolateral prefrontal cortex, ventrolateral prefrontal cortex, orbitofrontal cortex, premotor cortex, primary motor cortex, primary somatosensory cortex, and posterior parietal cortex. RESULTS: The eight thalamocortical projections were reconstructed in each hemisphere and the pathways were visualized: projections to the prefrontal cortex ascended through the anterior limb and genu of the internal capsule and anterior corona radiata. Projections to the premotor cortex passed through the genu and posterior limb of the internal capsule and middle corona radiata; in contrast, projections to the primary motor cortex, primary somatosensory cortex, and posterior parietal cortex ascended through the posterior limb of the internal capsule. No significant difference in fractional anisotropy, mean diffusivity, and fiber volume of all reconstructed thalamocortical projections was observed between the right and left hemispheres (p>0.05). CONCLUSION: We reconstructed the thalamocortical projections between the intralaminar thalamic nuclei and the frontoparietal cortex in normal subjects. We believe that our findings would be useful to clinicians involved in the care of patients with impaired consciousness and for researchers in studies of the ARAS.