Studies on Somnolence in the Daytime Caused by Drugs Used for Neuropathic Pain

Abstract

Abstract. In the present study, the characteristics of the sleep features of amitriptyline, mexiletine, and N-(4-tertiarybutylphenyl)-4-(3-cholorphyridin-2-yl)tetrahydropyradine-1(2H)-carbox-amide (BCTC) were studied. Electrodes were chronically implanted into the frontal cortex and the dorsal neck muscles of rats for electroencephalogram (EEG) and electromyogram (EMG) measurements, respectively. EEG and EMG were recorded with an electroencephalograph, and SleepSign ver. 2.0. was used for sleep-wake state analysis. Recordings were performed from 11:00 to 17:00. Amitriptyline caused significant decreases in sleep latency and total wake time and an increase in total non-rapid eye movement (non-REM) sleep time. Mexiletine caused a significant decrease in sleep latency, but no significant effect was observed in total wake time and total non-REM sleep time. On the other hand, BCTC, which is an antagonist of transient receptor potential vaniloid 1 (TRPV1), showed no significant effect on sleep latency, total wake time, total non-REM sleep time, and total REM sleep time. From these results, it can be concluded that a TRPV1 antagonist may become a useful drug for neuropathic pain without sedative side effects in the daytime, different from amitriptyline and mexiletine.

Effects of Some Antipsychotics and a Benzodiazepine Hypnotic on the Sleep-Wake Pattern in an Animal Model of Schizophrenia

“…Therefore, it is reasonable to presume that aripiprazole inhibits dopaminergic function in MK-801-treated rats. In addition, Hirase et al (11) reported that a 5-HT 1A -receptor agonist, tandspiron, caused a decrease in sleep latency in sleep-disturbed rats; therefore, it is reasonable to consider that the antagonistic activity of aripiprazole on the increase in sleep latency induced by MK-801 was exhibited via the 5-HT 1A receptor. As shown previously, risperidone caused an antagonizing effect on the increase in hourly awake time induced by MK-801, although the duration was relatively short.…”

Characteristic Effects of Anti-dementia Drugs on Rat Sleep Patterns

“…2.0, according to the previously described criteria (16,17). As a final step, the defined sleep-wake stages were examined visually and corrected if necessary.…”

“…2.0. The power spectrum densities, integrated and averaged, could be divided into 4 frequency areas: delta wave (0.5 -4 Hz), theta wave (4 -8 Hz), alpha wave (8 -13 Hz), and beta wave (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). Delta activity (%) was calculated by the following equation: Delta activity (%) = delta wave power density in the drug administration period / delta wave power density in the vehicle administration period in each animal × 100.…”

Effects of the 5-HT_1A Receptor Agonist Tandospirone on ACTH-Induced Sleep Disturbance in Rats

“…Recordings were conducted as described previously. 12,13) The signals were amplified and filtered (EEG, 0.5-30 Hz; EMG, 16-60 Hz), then digitized at a sampling rate of 128 Hz, and recorded by SleepSign ver. 2.0 (Kissei Comtec, Nagano, Japan) data acquisition program.…”