Biomaterial Database

In vitro electrical activity in the suprachiasmatic nucleus following splitting and masking of wheel-running behavior. 1991

P Zlomanczuk, and R R Margraf, and G R Lynch

Department of Biology, Wesleyan University, Middletown, CT 06459-01700.

Djungarian hamsters (Phodopus sungorus sungorus) were chronically exposed to constant light (60 lux) in order to generate a split rhythm of wheel-running behavior. The animals were killed and coronal hypothalamic slices prepared for extracellular recording from the left and right suprachiasmatic nuclei (SCN). Nine hamsters which exhibited a split in overt behavior also had bimodal peaks (280 cells) of SCN firing frequency (5.4 +/- 1.1 and 5.8 +/- 0.7 Hz); these peaks were about 180 degrees antiphase. Two troughs in firing frequency were also apparent (1.8 +/- 0.4 and 2.4 +/- 0.5 Hz) and coincided with the projected time of wheel-running activity. Differences in circadian pattern of electrical activity between the right and left SCN were not observed. When wheel-running activity in 5 hamsters was suppressed with high intensity (500 lux) constant light, the SCN firing profile (154 cells) failed to exhibit a daily rhythm. Firing frequency was consistently high (5.8 +/- 1.4 Hz) throughout the 24-h period. These results indicate that in vitro electrical activity of the SCN is related to overt behavior in Djungarian hamsters, in that high electrical activity occurs when locomotor activity is minimal.

UI	MeSH Term	Description	Entries
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D009043	Motor Activity	Body movements of a human or an animal as a behavioral phenomenon.	Activities, Motor,Activity, Motor,Motor Activities
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D002940	Circadian Rhythm	The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs or environmental and physiological stimuli.	Diurnal Rhythm,Nyctohemeral Rhythm,Twenty-Four Hour Rhythm,Nycthemeral Rhythm,Circadian Rhythms,Diurnal Rhythms,Nycthemeral Rhythms,Nyctohemeral Rhythms,Rhythm, Circadian,Rhythm, Diurnal,Rhythm, Nycthemeral,Rhythm, Nyctohemeral,Rhythm, Twenty-Four Hour,Rhythms, Circadian,Rhythms, Diurnal,Rhythms, Nycthemeral,Rhythms, Nyctohemeral,Rhythms, Twenty-Four Hour,Twenty Four Hour Rhythm,Twenty-Four Hour Rhythms
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
D006224	Cricetinae	A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.	Cricetus,Hamsters,Hamster
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013493	Suprachiasmatic Nucleus	An ovoid densely packed collection of small cells of the anterior hypothalamus lying close to the midline in a shallow impression of the OPTIC CHIASM.	Hypothalamic Suprachiasmatic Nuclei,Hypothalamic Suprachiasmatic Nucleus,Suprachiasmatic Nuclei,Suprachiasmatic Nuclei, Hypothalamic,Suprachiasmatic Nucleus, Hypothalamic
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In