Circadian rhythm in light response in suprachiasmatic nucleus neurons of freely moving rats.
نویسندگان
چکیده
Long-term recordings of single SCN units were performed in freely moving rats simultaneously with multiunit recordings and evidence is presented for a daily change in light-responsiveness. SCN light response is high during the night and low during the day. We conclude that this difference is caused by a change in sensitivity, with higher sensitivities at night. Moreover, we demonstrate that the circadian rhythm in SCN light response is the result of the integrated behaviour of similarly behaving single SCN units.
منابع مشابه
Light responsiveness of the suprachiasmatic nucleus: long-term multiunit and single-unit recordings in freely moving rats.
The suprachiasmatic nuclei (SCN) of the hypothalamus contain a pacemaker that generates circadian rhythms in many functions. Light is the most important stimulus that synchronizes the circadian pacemaker to the environmental cycle. In this paper we have characterized the baseline neuronal firing patterns of the SCN as well as their response to light in freely moving rats. Multiunit and single-u...
متن کاملOpposing effects of behavioural activity and light on neurons of the suprachiasmatic nucleus.
The mammalian circadian pacemaker is located in the suprachiasmatic nuclei. It can be shifted in phase by photic cues and by the behavioural activity of the animal. When presented together, light and behavioural activity attenuate each others' phase-shifting effect. Still unclear is how behavioural activity affects the suprachiasmatic nuclei and how it interacts with photic information. Previou...
متن کاملNMDA-evoked calcium transients and currents in the suprachiasmatic nucleus: gating by the circadian system.
A variety of evidence suggests that the effects of light on the mammalian circadian system are mediated by glutamatergic mechanisms and that the N-methyl- D-aspartate (NMDA) receptor plays an important role in this regulation. One of the fundamental features of circadian oscillators is that their response to environmental stimulation varies depending on the phase of the daily cycle when the sti...
متن کاملIn Vivo Monitoring of Multi-Unit Neural Activity in the Suprachiasmatic Nucleus Reveals Robust Circadian Rhythms in Period1−/− Mice
The master pacemaker in the suprachiasmatic nucleus (SCN) controls daily rhythms of behavior in mammals. C57BL/6J mice lacking Period1 (Per1⁻/⁻) are an anomaly because their SCN molecular rhythm is weak or absent in vitro even though their locomotor activity rhythm is robust. To resolve the contradiction between the in vitro and in vivo circadian phenotypes of Per1⁻/⁻ mice, we measured the mult...
متن کاملVasopressin-deficient suprachiasmatic nucleus grafts re-instate circadian rhythmicity in suprachiasmatic nucleus-lesioned arrhythmic rats.
It was investigated whether grafts of the suprachiasmatic nucleus could re-instate circadian rhythmicity in the absence of its endogenous vasopressin production and whether the restored rhythm would have the long period length of the donor. Grafts of 17-days-old vasopressin-deficient homozygous Brattleboro rat fetuses, homotopically placed in arrhythmic suprachiasmatic nucleus-lesioned Wistar r...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Brain research
دوره 741 1-2 شماره
صفحات -
تاریخ انتشار 1996