Effects of damage to the suprachiasmatic area of the anterior hypothalamus on the daily melatonin and cortisol rhythms in the rhesus monkey.

摘要: The effects of lesions the suprachiasmatic nucleus (SCN) on circadian rhythms in melatonin and cortisol were examined rhesus monkey. concentrations two hormones monitored cerebrospinal fluid (CSF) withdrawn from sham-operated animals, animals with complete bilateral SCN lesions, partial damage at 4 8 months after surgery. In sham- operated as intact animal, daily rhythm was entrained to light-dark cycle, suppressed constant light, persisted darkness. contrast, neither animal ablation exhibited a pattern CSF diurnal lighting surgery nor their levels low values. Furthermore, not either by light. Surprisingly, surgery, spectral analysis revealed 24-hr component patterns for each both lighting, but light did suppress consistently. Daily 6 1/2-d period study contrast alterations damage, there no apparent effect or rhythm. These data indicate that, monkey, is important generation, photic entrainment, suppression However, oscillators located outside region may control normal perhaps absence SCN.