Biomaterial Database

Diurnal rhythm of total and free concentrations of serum corticosterone in the rat. 1982

J D'Agostino, and G F Vaeth, and S J Henning

Daily variations in serum concentrations of total and free corticosterone and corticosteroid-binding globulin (CBG) were determined at 4 h intervals in male rats maintained on a 12:12 h light/dark cycle (lights on at 05.00 h). Total corticosterone concentrations exhibited a classical rhythm with peak values occurring at the onset of dark (17.00 h). Serum CBG concentrations displayed daily fluctuations but these appeared to be non-rhythmic in nature. The % free corticosterone exhibited a diurnal rhythm with peak values occurring during the dark phase. When absolute concentrations of free corticosterone were calculated, the profile could be superimposed on that of total corticosterone with the zenith at the onset of the dark phase (17.00 h) and the nadir coinciding with the onset of light (05.00 h). These data suggest that the primary determinant of the rhythm in free corticosterone concentrations is the daily rhythm in total corticosterone.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
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
D003345	Corticosterone	An adrenocortical steroid that has modest but significant activities as a mineralocorticoid and a glucocorticoid. (From Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1437)
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
D014156	Transcortin	A serpin family member that binds to and transports GLUCOCORTICOIDS in the BLOOD.	Corticosteroid-Binding Globulin,Serpin A6,Corticosteroid Binding Globulin
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus