title: Photoreceptors in the teleost pineal organ. Daily fluctuations of indole metabolism.
abstract: The present study in the pineal organ of the pike reports the existence of day/night variations in the levels of three indoles, and in the activity of two enzymes involved in their metabolism. Present and previous data indicate that the cone-like (P) and modified (MP) photoreceptors of the pineal organ translate the photoperiodic information into nervous and indolic (in P), or into indolic (in MP) signals, displaying circadian variations. It is questioned whether these cells which are functional units of the circadian system, contain a circadian oscillator.
mesh_terms: D000818:Animals; D002940:Circadian Rhythm; D007211:Indoles / Q000378:metabolism*; D010786:Photoreceptor Cells / Q000378:metabolism*; D010870:Pineal Gland / Q000378:metabolism*; D012487:Salmonidae / Q000378:metabolism*
chemical_list: D007211:Indoles