Regulation and possible role of serotonin N-acetyltransferase in the retina. Fed Proc 1984 Sep;43(12):2704-8
Date
09/01/1984Pubmed ID
6468668Scopus ID
2-s2.0-0021245297 (requires institutional sign-in at Scopus site) 30 CitationsAbstract
The activity of retinal serotonin N-acetyltransferase (NAT) (arylamine acetyltransferase, EC 2.3.1.5), the penultimate enzyme in melatonin biosynthesis, exhibits properties of a circadian rhythm comparable to that seen in the pineal gland. Using an eye cup preparation we have found that circadian properties persist in vitro, which indicates that an endogenous circadian oscillator controlling NAT is present in the eye. Nighttime increases in NAT activity are suppressed by light, protein synthesis inhibitors, and catecholamines. In light, NAT activity is induced by conditions expected to increase intracellular levels of cyclic AMP (cAMP). This suggests that catecholamines and cAMP are normally involved in the regulation of NAT. Circadian indoleamine metabolism may play a role in the control of rhythmic photoreceptor metabolism as evidenced by the observation that melatonin and related compounds are potent activators of disk shedding.
Author List
Besharse JC, Dunis DA, Iuvone PMAuthor
Joseph C. Besharse PhD, MA Emeritus Professor in the Cell Biology Neurobiology and Anatomy department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AcetyltransferasesAnimals
Arylamine N-Acetyltransferase
Circadian Rhythm
Darkness
Enzyme Activation
Kinetics
Light
Melatonin
Retina
Xenopus
