Regulation of melatonin synthesis in rainbow trout (Oncorhyncus mykiss) pineal organs: effects of calcium depletion and calcium channel drugs. Gen Comp Endocrinol 1997 Feb;105(2):210-7
Date
02/01/1997Pubmed ID
9038253DOI
10.1006/gcen.1996.6822Scopus ID
2-s2.0-0031080897 (requires institutional sign-in at Scopus site) 7 CitationsAbstract
The effects of calcium depletion and of three calcium channel drugs on melatonin synthesis in pineal organs of rainbow trout (Oncorhyncus mykiss) were examined. Dark-induced melatonin synthesis was inhibited by calcium depletion, by treatment with nitrendipine (NTR), an antagonist of the L-type voltage-sensitive calcium channel, and by treatment with omega-Conotoxin GVIA, an antagonist of the N-type voltage-sensitive calcium channel. Bay K 8644, an agonist of the L-type channel, had no significant effect on pineal melatonin synthesis. These data represent evidence that calcium entry into trout pineal photoreceptor cells through voltage-sensitive calcium channels is important in the maintenance of dark-induced melatonin synthesis and that light's inhibitory effect on melatonin synthesis may be mediated by closure of these channels. NTR-induced inhibition of dark-induced melatonin synthesis was abolished when dibutyryl cyclic AMP (db-cAMP) was administered to NTR-treated pineal organs, suggesting that calcium acts upstream of cAMP in regulating melatonin synthesis.
Author List
Gasser PJ, Gern WAAuthor
Paul Gasser BS,MS,PhD Assistant Professor in the Biomedical Sciences department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl esterAnimals
Calcium
Calcium Channel Blockers
Cyclic AMP
Dose-Response Relationship, Drug
Melatonin
Nitrendipine
Oncorhynchus mykiss
Organ Culture Techniques
Peptides
Pineal Gland
Time Factors
omega-Conotoxin GVIA
