Sleep patterns of the volcano mouse (Neotomodon alstoni alstoni).

Sleep-waking patterns of the volcano mouse were studied under laboratory conditions. This rodent exhibits four states of vigilance: active wakefulness (Aw), quiet wakefulness (Qw), slow-wave sleep (SWS), and paradoxical (PS), or rapid-eye movement (REM) sleep. These states present, in general, the classic mammalian electrophysiological patterns. Although sleep periods were distributed at any time of the nychthemeral cycle, they showed the tendency to concentrate between 0800 and 2000 hours. The volcano mouse may be considered as a "good" sleeper, because it shows a relatively high percentage of sleep from the total recording time (TRT). Slow-wave sleep occupied 64.54 +/- 8.84% (mean +/- SD) of the total recording time, while 7.56 +/- 1.31% corresponded to rapid-eye movement sleep. The average duration of the rapid-eye movement sleep phase was 126.48 +/- 17.79 s, exhibiting an average recurrence of 49 +/- 9.28 phases throughout the nychthemeral cycle. Mean duration of the sleep cycle was 9.23 +/- 2.36 min. Quantitative data of the volcano mouse sleep may be considered adequate for its body size and characteristic of an animal which sleeps in secure places under free-living conditions.

[Effects of 1,5 benzodiazepine beta lactam on sleep]. / Efecto de una beta lactama de 1.5 benzodiazepina sobre el sueño.

Various substances have been used as sleep inductors, but their use has declined, due to their undesirable side effects, and they have been replaced mainly by benzodiazepines. There currently exists a great variety of benzodiazepines with an increasing, clinical use, although they also present certain disadvantages. The effect on sleep of the intraperitoneal administration (0.9 mg/kg) of 7-(p-cl-phenyl)-8-phenoxy-4,5-benzo-3-aza-2-none, was analysed in chronically implanted wistar rats. Results indicate that this substance decreases wakefulness and increases significantly slow-wave and paradoxical sleep. Latency of the first phase of paradoxical sleep show a tendency to increase. It is concluded that this substance has hypnogenic effects.

[Effect of a derivative of 1,5 benzodiazepine on sleep]. / Efecto de un derivado de la 1,5 benzodiazepina sobre el sueño.

The object of this investigation was to study the effect of a benzodiazepine upon the cycle wakefulness-sleep. Wistar rats received 0.9 mg/kg of the chlorate derivative of beta lactam 1.5 benzodiazepine intraperitoneally and the action was analyzed by means of continuous polygraphic registers for ten hours long. Results indicate that this substance decreases wakefulness and slightly increases slow wave sleep. Paradoxical sleep increases significantly (p less than 0.05). Latency of the first phase of paradoxical sleep decreases considerably. These effects suggest that this compound favors sleep under present experimental conditions.