title: Action spectrum of the retinal mechanism mediating nocturnal light-induced suppression of rat pineal gland N-acetyltransferase.
abstract: The spectral properties of the retinal mechanism mediating the inhibitory effects of nocturnal light on pineal gland N-acetyltransferase (NAT) activity were determined. Pineal gland NAT activity declined linearly in albino rats exposed to different irradiances of a 460 or 580 nm monochromatic light during the middle of the dark phase of the cycle. The difference in sensitivity to the test lights is that predicted for a photopigment having peak absorbance at 495 nm, suggesting the inhibition of pineal gland N-acetyltransferase activity is mediated by the photopigment found in rat rods.
mesh_terms: D000123:Acetyltransferases / Q000378:metabolism*; D000818:Animals; D001191:Arylamine N-Acetyltransferase / Q000378:metabolism*; D005260:Female; D008027:Light; D008297:Male; D010786:Photoreceptor Cells / Q000528:radiation effects*; D010870:Pineal Gland / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D012168:Retinal Pigments / Q000528:radiation effects*
chemical_list: D012168:Retinal Pigments; D000123:Acetyltransferases; D001191:Arylamine N-Acetyltransferase