Publication | Closed Access
A CORRELATIVE STUDY OF ENDOCRINE RHYTHMS IN RATS
59
Citations
0
References
1968
Year
Pituitary VasopressinSocial SciencesPituitary TshPituitary GlandParallel Circadian PeriodicityNeuroendocrine MechanismCircadian RhythmAnimal PhysiologySleepAlertnessEndocrine MechanismHypothalamusNervous SystemEndocrinologyMelatoninCircadian BiologyNeurophysiologyPhysiologyNeuroendocrine DisorderNeuroscienceMedicineChronobiology
ABSTRACT Several endocrine rhythms have been studied simultaneously in the same group of rats under resting conditions. A parallel circadian periodicity was found for adrenal and plasma corticosterone, pituitary and plasma ACTH, and for the first time, for pituitary vasopressin. These rhythms are typical for nocturnal animals, demonstrating a distinct peak before the onset of darkness and lowest values at the beginning of the light period. An opposite behaviour was found for pituitary TSH in male rats showing a significant fall at the peak time of the other hormones, whereas in female rats this fluctuation was not observed. No CRF-like material could be obtained from hypothalamic tissue under resting conditions. The methods used in this study and the results obtained are discussed together with the relevant literature.