Melatonin: daily cycle in plasma and cerebrospinal fluid of calves.

@article{Hedlund1977MelatoninDC,
  title={Melatonin: daily cycle in plasma and cerebrospinal fluid of calves.},
  author={Laurence Hedlund and M M Lischko and Mark D. Rollag and Gordon D. Niswender},
  journal={Science},
  year={1977},
  volume={195 4279},
  pages={686-7}
}
Melatonin was measured by radioimmunoassay in jugular vein plasma and lateral ventricle cerebrospinal fluid collected from calves at 12 times of the day and night. Melatonin in cerebrospinal fluid increased 17-fold from an average (+/- standard error) of 38 +/- 8 picograms per milliliter during the day to an average of 637 +/- 133 picograms per milliliter during the night (P less than .001). Plasma concentrations of melatonin increased sixfold from an average, per milliliter, of 19 +/- 4… CONTINUE READING