Journal ArticleDOI
Plasma, Cerebrospinal Fluid, and Brain Distribution of 14C‐Melatonin in Rat: A Biochemical and Autoradiographic Study
Reads0
Chats0
TLDR
Chromatographic analysis indicated that the radioactivity from biological samples taken at various times following the injection of label was mainly associated with 14C‐MT, which was found in cortex, thalamic nuclei, medial geniculate nucleus, anterior pretectal area, paraventricular nucleus of the hypothalamus, choroid plexuses, and bulb‐pons.Abstract:
The distribution of 14C-Melatonin (14C-MT) after systemic injection was studied in the plasma, cerebrospinal fluid (CSF), and brain of rats. Chromatographic analysis (thin-layer chromatography and high-performance liquid chromatography) indicated that the radioactivity from biological samples taken at various times following the injection of label was mainly associated with 14C-MT. Computer analysis of plasma 14C-MT kinetics showed a three-compartment system with half-lives of 0.21 +/- 0.05, 5.97 +/- 1.11, and 47.52 +/- 8.86 min. The volume of distribution and the clearance were 1,736 +/- 349 ml.kg-1 and 25.1 +/- 1.7 ml.min-1.kg-1 respectively. The entry of 14C-MT into the CSF was rapid and reached a maximum at 5 min. The decay followed a two-compartment system with half-lives of 16.5 +/- 2.9 and 47.3 +/- 8.6 min. The CSF/plasma concentration ratio was 0.38 at the steady state (30 min). At 2 min the level of 14C-MT in the brain was 3.8 higher than in the CSF. Representative autoradiograms revealed an heterogeneous localization of 14C-MT in the grey matter. The highest regional values, as evaluated by the permeability area product technique, were found in cortex, thalamic nuclei, medial geniculate nucleus, anterior pretectal area, paraventricular nucleus of the hypothalamus, choroid plexuses, and bulb-pons. Thirty minutesmore » later 14C-MT was still detected in most of the brain regions analyzed. These results point to a low but rapid penetration of circulating MT into the brain and the CSF. The heterogeneous distribution and the partial retention of 14C-MT in the brain are compatible with the hypothesis of a central action of this hormone mediated via binding sites.« lessread more
Citations
More filters
Journal ArticleDOI
Brief report: Circadian melatonin, thyroid-stimulating hormone, prolactin, and cortisol levels in serum of young adults with autism
TL;DR: There appears to be a tendency for various types of neuroendocrinological abnormalities in autistics, and melatonin, as well as possibly TSH and perhaps prolactin, could serve as biochemical variables of the biological parameters of the disease.
Journal ArticleDOI
Melatonin reduces the severity of anesthesia-induced apoptotic neurodegeneration in the developing rat brain.
TL;DR: Melatonin-induced neuroprotection was mediated, at least in part, via the inhibition of mitochondria-dependent apoptotic pathway since melatonin caused an up-regulation of the anti-apoptotic protein, bcl-X(L), reduction in anesthesia-induced cytochrome c release into the cytoplasm and a decrease in anesthesia's activation of caspase-3, an important step in the activation of DNAses and the formation of the apoptotic bodies.
Journal ArticleDOI
Urinary metabolomics of young Italian autistic children supports abnormal tryptophan and purine metabolism
TL;DR: The metabolic pathways most distinctive of young Italian autistic children largely overlap with those found in rodent models of ASD following maternal immune activation or genetic manipulations, and could contribute to autism severity.
Journal ArticleDOI
Melatonin in relation to physiology in adult humans.
TL;DR: Melatonin has sleep inducing properties, and exerts important activities in the regulation of circadian rhythms, and could be important in slowing the processes of ageing by acting as an antioxidant.
Journal ArticleDOI
Which neuroprotective agents are ready for bench to bedside translation in the newborn infant
Nicola J. Robertson,Sidhartha Tan,Floris Groenendaal,Frank van Bel,Sandra E. Juul,Laura Bennet,Matthew Derrick,Stephen A. Back,Raul Chavez Valdez,Frances J. Northington,Alistair J. Gunn,Carina Mallard +11 more
TL;DR: In this article, a comparison of antenatal and postnatal treatments for perinatal hypoxia-ischemia-related brain injury in term newborn infants is presented. But, there is no consensus at present on which drugs have a high chance of success for either antenatal or postnatal treatment, and there are insufficient societal resources available to test them all.
References
More filters
Journal ArticleDOI
The Rat Brain in Stereotaxic Coordinates, George Paxinos, Charles Watson (Eds.). Academic Press, San Diego, CA (1982), vii + 153, $35.00, ISBN: 0 125 47620 5
TL;DR: It is shown here how the response of the immune system to repeated exposure to high-energy radiation affects its ability to discriminate between healthy and diseased tissue.
Journal ArticleDOI
Measurement of local cerebral blood flow with iodo [14C] antipyrine
TL;DR: Iodo[14C]antipyrine appears, therefore, to be a satisfactory nonvolatile tracer for the measurement of local cerebral blood flow.
Journal ArticleDOI
Melatonin: A Coordinating Signal for Mammalian Reproduction?
TL;DR: In seasonally breeding mammals that use changes in the photoperiod to time their reproductive cycles, temporal signals to the reproductive system are controlled by the daily rhythm in melatonin production.
Journal ArticleDOI
Insulin effects on monovalent cation transport and Na-K-ATPase activity.
TL;DR: The hypothesis that at least part of the increase in monovalent cation active transport produced by insulin is related to enhanced Na-K-ATPase activity is supported and the latter phenomenon is dependent on some components or properties of the intact cell.