The Suppression of Pineal Melatonin Content and<i>N</i>-AcetyItransferase Activity by Different Light Irradiances in the Syrian Hamster: A Dose-Response Relationship<sup>*</sup>
EndocrinologyPublished 1 July 1983
George C. Brainard, Bruce A. Richardson, Thomas S. King, Susan A. Matthews, Rüssel J. Reiter
Citations140
SJR quartileQ1
SJR score1.31
SNIP1.01
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TL;DR
Both pineal NAT and melatonin were similarly depressed by the light irradiances in a dose-related manner, and may be relevant to the physiological control of the pineal by natural illumination.
Abstract
The purpose of this study was to test the influence of various irradiances of cool white fluorescent light on the suppression of pineal N-acetyltransferase activity (NAT) and melatonin content in hamsters. Groups of animals were exposed to light irradiances ranging from 0.00-1.86 microwatts (microW)/cm2 for 20 min during the night. Both pineal NAT and melatonin were similarly depressed by the light irradiances in a dose-related manner. The shape of the resultant dose-response curves and the calculated ED50 for NAT (0.066 microW/cm2) and melatonin (0.058 microW/cm2) were remarkably similar. These findings may be relevant to the physiological control of the pineal by natural illumination.
Keywords
MedicineNeuroscience
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