title: [The circadian rhythm of the adrenal glucocorticoid function in female rats selected for the reaction of the estrous cycle to constant illumination].
abstract: Studies have been made of the circadian rhythms of a glucorticoid hormone, corticosterone, in the adrenals and blood serum in female Wistar rats from two substrains selected for high (ESTH) and low (ESTL) ability to develop permanent oestrus under constant illumination. Significant changes in parameters of the circadian rhythm of the hormone were observed in animals of the 26th generation of selection. Total alleviation of corticosterone rhythm in the blood was on observed in ESTL rats, while in ESTH animals maximum level of the hormone in the blood was shifted to the dark time. Comparison of a high corticosterone content of the adrenals in ESTL rats with a low concentration in the blood plasma indicates the increase in metabolic clearance of the hormone in animals from this strain. It is suggested that the decreased corticosteroid production in the adrenals of ESTH rats facilitates the development of permanent oestrus under constant illumination.
authors.forename: D V
authors.initials: DV
authors.lastname: Kliuchkov
authors.forename: V A
authors.initials: VA
authors.lastname: Shul'ga
mesh_terms: D015062:11-Hydroxycorticosteroids / Q000032:analysis / Q000528:radiation effects; D000311:Adrenal Glands / Q000502:physiology / Q000528:radiation effects*; D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology / Q000528:radiation effects*; D004971:Estrus / Q000502:physiology / Q000528:radiation effects*; D005260:Female; D005938:Glucocorticoids / Q000502:physiology / Q000528:radiation effects*; D008027:Light; D051381:Rats; D011919:Rats, Inbred Strains; D012641:Selection, Genetic; D013997:Time Factors
chemical_list: D015062:11-Hydroxycorticosteroids; D005938:Glucocorticoids
vernacular_title: Sutochnyĭ ritm gliukokortikoidnoĭ funktsii nadpochechnikov samok krys, selektsionirovannykh po reaktsii éstral'nogo tsikla k postoiannomu osveshcheniiu.