Suprachiasmatic nuclei lesions do not eliminate the circadian rhythms of electrolyte excretion in the rat.
The 24-hour variations in 2-hour diuretic and saluretic action of furosemide (4 mg/kg) given at 8, 12, 16, 20, 24 or 4 hr and the circadian rhythms of food and water intake, urine and electrolyte excretion followed for two consecutive days at 4-hour intervals were investigated in suprachiasmatic nuclei (SCN)-lesioned or sham-operated male Wistar rats. The results showed that: a distinct 24-hour rhythm in furosemide-induced urine, sodium and chloride excretion persisted after SCN lesions, and the lesions abolished the circadian rhythms of food and water intake but only desynchronized the individual 24-hour variations in electrolyte excretion. We concluded that SCN play a role as a central synchronizer but not as a major oscillator of the circadian rhythms of electrolyte excretion in the rat.
D000818:Animals; D002712:Chlorides / Q000652:urine; D002940:Circadian Rhythm; D004231:Diuresis; D004326:Drinking; D004435:Eating; D005665:Furosemide / Q000494:pharmacology; D008297:Male; D009318:Natriuresis; D011188:Potassium / Q000652:urine; D051381:Rats; D011919:Rats, Inbred Strains; D013493:Suprachiasmatic Nucleus / Q000502:physiology*
D002712:Chlorides; D005665:Furosemide; D011188:Potassium