Document Detail


Studies on the kinetics of melatonin and N-acetylserotonin in the rat at mid-light and mid-dark.
MedLine Citation:
PMID:  6545818     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The distribution and disappearance of melatonin and N-acetylserotonin after intravenous injection were studied at mid-light and mid-dark. Male rats were adapted under a photoperiod of 12 h light and 12 h dark cycle for a minimum of 1 week. After the intravenous injection of melatonin (10 micrograms), N-acetylserotonin (10 micrograms), or 3H-melatonin (76 ng), blood samples were collected at 1, 3, 5, 10, 20, 30, 45, 60, 75, 90, and 120 min. The concentrations of indoles in the plasma samples were determined by radioimmunoassay, while the radioactivity of 3H-melatonin was determined by scintillation counting. The distribution of melatonin and N-acetylserotonin followed a two-compartment model, showing an initial distribution phase followed by an elimination phase. The biological half-life of melatonin at mid-light and mid-dark were similar but the volume of distribution (V beta and Vc) and metabolic clearance rate (C1s) were greater at mid-dark than at mid-light. The estimated melatonin secretory rate at mid-dark was fivefold greater than that at mid-light. When 3H-melatonin was used, the half-life was significantly longer. A diurnal difference in the distribution was also evident in the N-acetylserotonin studies. The volume of distribution (V beta and Vc) was greater at mid-dark while the C1s was not significantly faster at mid-dark compared with that at mid-light. However, the estimated N-acetylserotonin secretory rate at mid-dark was eightfold greater than at mid-light.
Authors:
M Y Chan; S F Pang; P L Tang; G M Brown
Related Documents :
8580448 - Evidence for local synthesis of melatonin in golden hamster retina.
12017768 - Cyclic melatonin synchronizes the circadian rhythm of feeding activity in japanese quai...
9714458 - 5-methoxytryptophol rhythms in the chick pineal gland: effect of environmental lighting...
17506898 - Extracellular ascorbate modulates glutamate dynamics: role of behavioral activation.
18466408 - In the footsteps of biological motion and multisensory perception: judgments of audiovi...
20725368 - Quantized complex ferroelectric liquid crystal spatial light modulators.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Journal of pineal research     Volume:  1     ISSN:  0742-3098     ISO Abbreviation:  J. Pineal Res.     Publication Date:  1984  
Date Detail:
Created Date:  1986-05-01     Completed Date:  1986-05-01     Revised Date:  2003-11-14    
Medline Journal Info:
Nlm Unique ID:  8504412     Medline TA:  J Pineal Res     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  227-36     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Circadian Rhythm*
Darkness
Injections, Intravenous
Kinetics
Light
Male
Melatonin / administration & dosage,  blood*
Radioimmunoassay
Rats
Rats, Inbred Strains
Serotonin / administration & dosage,  analogs & derivatives*,  blood
Chemical
Reg. No./Substance:
1210-83-9/N-acetylserotonin; 50-67-9/Serotonin; 73-31-4/Melatonin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Characterization of dopaminergic receptor sites in bovine pineal gland.
Next Document:  Effects of experimentally induced chronic hyperprolactinemia on the ultrastructure of pinealocytes i...