Possible involvement of the S-adenosyl-L-homocysteine metabolites, adenosine and L-homocysteine, in sleep in rats.

The effects of i.p. injections of adenosine (Ado) and homocysteine at 17.

A comparison of the effects of S-adenosyl-L-homocysteine on sleep in normal and pinealectomized rats.

S-adenosyl-L-homocysteine (SAH) was administered to normal and pinealectomized rats previously implanted with electrodes for polygraphic recording. In normal rats, injected at 17.00 h, 7 mg/kg SAH induced a significant increase of paradoxical sleep (PS) during the night.

Increase of paradoxical sleep by electrical stimulation within lateral ventricles of rat.

The effect on the sleep-waking cycle of low intensity electrical stimulation (0.2 mA intensity, 80 Hz frequency, 0.7 ms signal duration) within the lateral ventricles was studied in rats maintained under a photoperiod of 12 h light and 12 h darkness (lights on at 06.

Polygraphic evidence against a critical role of the raphe nuclei in sleep in the rat.

The role of the raphe nuclei (RN) in sleep and waking has been investigated in 35 male Wistar rats. After an habituation period to their environment, the rats were continuously recorded (24 h/day), during a 5 day period prior to the lesioning of one or several RN and thereafter during 22 days. The daily slow wave sleep (SWS) and paradoxical sleep (PS) amounts from the 18th to the 22nd day after the lesion were used to classify the rats.

Suprachiasmatic nuclei lesions in the rat: alterations in sleep circadian rhythms.

After continuous control recording (24 h/day) during 5 days, 14 rats received sham, complete or incomplete lesions of the suprachiasmatic nuclei (SCN). Sleep records were analysed from the 22nd to the 27th day after the lesion. In rats with complete lesions of the SCN, there was a strong decrease in the amplitude of the circadian variation in slow wave (SWS) and paradoxical (PS) sleep.