Rapid light-induced decrease in pineal serotonin N-acetyltransferase activity

Science. 1972 Aug 11;177(4048):532-3. doi: 10.1126/science.177.4048.532.


Light acting by way of the eye causes the dark-induced activity of serotonin N-acetyltransferase in the pineal gland of the rat to decrease with a halving time of about 3 minutes. This effect, which is one of the more rapid physiological changes known to occur in the activity of any enzyme that metabolizes biogenic amines, appears to explain the rapid increase in the concentration of pineal serotonin that is caused by light exposure at night.

MeSH terms

  • Acyltransferases / metabolism*
  • Adaptation, Ocular
  • Adaptation, Physiological
  • Animals
  • Blindness
  • Circadian Rhythm
  • Enzyme Activation
  • Light*
  • Male
  • Photic Stimulation
  • Pineal Gland / enzymology*
  • Rats
  • Rats, Inbred Strains
  • Serotonin
  • Time Factors


  • Serotonin
  • Acyltransferases