title: Plasma tryptophan and sheep.
abstract: Free, bound, and total plasma tryptophan (F.P.T., B.P.T., and T.P.T.) levels have been measured throughout the night in six young female volunteers. All-night polygraphic sleep recordings were also made. No direct temporal relationship was found between plasma tryptophan levels and specific sleep stages. The mean F.P.T. levels, however, were found to have a positive correlation with rapid-eye-movement (R.E.M.) sleep and a negative correlation with non-R.E.M. sleep. An inverse relationship existed between the F.P.T. and B.P.T. levels. There appeared to be a diurnal variation in F.P.T. levels, with high readings in the first half of the night.
mesh_terms: D000305:Adrenal Cortex Hormones / Q000502:physiology; D002940:Circadian Rhythm; D004032:Diet; D004569:Electroencephalography; D005260:Female; D006801:Humans; D011485:Protein Binding; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages / Q000502:physiology; D012895:Sleep, REM / Q000502:physiology; D013997:Time Factors; D014364:Tryptophan / Q000097:blood*
chemical_list: D000305:Adrenal Cortex Hormones; D014364:Tryptophan