Matches in SemOpenAlex for { <https://semopenalex.org/work/W2000276240> ?p ?o ?g. }
Showing items 1 to 89 of
89
with 100 items per page.
- W2000276240 endingPage "13" @default.
- W2000276240 startingPage "4" @default.
- W2000276240 abstract "The present study tested the hypothesis that daily melatonin treatments influence the biological clock mechanism controlling the circadian melatonin rhythm. Adult male and female Djungarian hamsters in light:dark = 16L:8D (lights on 0300-1900 h) were administered melatonin subcutaneously (s.c.) each day (5 μg/0.2 ml saline) in the morning at 1000 h (AM) or late afternoon at 1700 h (PM); controls received a vehicle injection (CON). After 14 days, pineal and serum melatonin concentrations were determined at various times on the last day of treatment and the next day in constant darkness (no treatment). The rhythm in pineal gland melatonin content was similar in each of the three groups on the last day of treatment (about 6 h duration). On the next day in constant dark, the rising phase was advanced and duration extended by 2 h or more in melatonin-treated hamsters compared to that in CONs (ANOVA). In circulation, the melatonin rhythm in AM and PM groups was phase advanced (onset and peak) on both days of the study. Thus duration was extended by up to 4.5 h compared to that in saline-treated controls. Moreover, amplitude of the nighttime serum melatonin rise was elevated up to fivefold relative to that in the CON group (ANOVA and Accumulated Sums analysis). The effects of repeated melatonin treatments on amplitude and phase of the serum melatonin rhythm raise the possibility that the circadian clock that controls pineal gland production of melatonin may also regulate melatonin secretion. From this and another study, the apparent half-life of melatonin in circulation was estimated to be 7.5 min; the melatonin injection initially produced pharmacological concentrations that were followed by low serum melatonin levels within 2 h. Thus, in both melatonin treatment groups, the data suggest that two distinct periods of elevated serum melatonin were present each day The cellular mechanism for melatonin action must take into consideration how a brief interruption in elevated melatonin in circulation (about 1 h in the PM group) is recognized as a continuous duration (short daylength), whereas a more extended baseline period is transduced as an abbreviated or long daylength (about 7 h in the AM group). These data further suggest that the biological clock mechanism that generates the circadian melatonin rhythm is responsive to the influence of daily melatonin treatments and presumably to the feedback action of endogenous melatonin on its own rhythm in the Djungarian hamster in long days." @default.
- W2000276240 created "2016-06-24" @default.
- W2000276240 creator A5080977254 @default.
- W2000276240 date "1996-03-01" @default.
- W2000276240 modified "2023-09-27" @default.
- W2000276240 title "Daily Melatonin Treatments Regulate the Circadian Melatonin Rhythm in the Adult Djungarian Hamster" @default.
- W2000276240 cites W1970455982 @default.
- W2000276240 cites W1974854913 @default.
- W2000276240 cites W1981589604 @default.
- W2000276240 cites W1983770547 @default.
- W2000276240 cites W1992690540 @default.
- W2000276240 cites W1996361779 @default.
- W2000276240 cites W2004547406 @default.
- W2000276240 cites W2010188879 @default.
- W2000276240 cites W2023076009 @default.
- W2000276240 cites W2023104487 @default.
- W2000276240 cites W2025749207 @default.
- W2000276240 cites W2032674369 @default.
- W2000276240 cites W2044743814 @default.
- W2000276240 cites W2050926729 @default.
- W2000276240 cites W2051733271 @default.
- W2000276240 cites W2054226412 @default.
- W2000276240 cites W2055094952 @default.
- W2000276240 cites W2057625080 @default.
- W2000276240 cites W2058447498 @default.
- W2000276240 cites W2066115447 @default.
- W2000276240 cites W2078334583 @default.
- W2000276240 cites W2079962268 @default.
- W2000276240 cites W2085019942 @default.
- W2000276240 cites W2093769918 @default.
- W2000276240 cites W2097269583 @default.
- W2000276240 cites W2124266467 @default.
- W2000276240 cites W2133536004 @default.
- W2000276240 cites W2163920027 @default.
- W2000276240 cites W2316093583 @default.
- W2000276240 cites W2331537529 @default.
- W2000276240 doi "https://doi.org/10.1177/074873049601100101" @default.
- W2000276240 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/8695891" @default.
- W2000276240 hasPublicationYear "1996" @default.
- W2000276240 type Work @default.
- W2000276240 sameAs 2000276240 @default.
- W2000276240 citedByCount "20" @default.
- W2000276240 countsByYear W20002762402013 @default.
- W2000276240 crossrefType "journal-article" @default.
- W2000276240 hasAuthorship W2000276240A5080977254 @default.
- W2000276240 hasConcept C121446783 @default.
- W2000276240 hasConcept C126322002 @default.
- W2000276240 hasConcept C134018914 @default.
- W2000276240 hasConcept C135343436 @default.
- W2000276240 hasConcept C19720800 @default.
- W2000276240 hasConcept C2777397205 @default.
- W2000276240 hasConcept C2778182776 @default.
- W2000276240 hasConcept C2778575167 @default.
- W2000276240 hasConcept C2780059843 @default.
- W2000276240 hasConcept C71924100 @default.
- W2000276240 hasConcept C86803240 @default.
- W2000276240 hasConceptScore W2000276240C121446783 @default.
- W2000276240 hasConceptScore W2000276240C126322002 @default.
- W2000276240 hasConceptScore W2000276240C134018914 @default.
- W2000276240 hasConceptScore W2000276240C135343436 @default.
- W2000276240 hasConceptScore W2000276240C19720800 @default.
- W2000276240 hasConceptScore W2000276240C2777397205 @default.
- W2000276240 hasConceptScore W2000276240C2778182776 @default.
- W2000276240 hasConceptScore W2000276240C2778575167 @default.
- W2000276240 hasConceptScore W2000276240C2780059843 @default.
- W2000276240 hasConceptScore W2000276240C71924100 @default.
- W2000276240 hasConceptScore W2000276240C86803240 @default.
- W2000276240 hasIssue "1" @default.
- W2000276240 hasLocation W20002762401 @default.
- W2000276240 hasLocation W20002762402 @default.
- W2000276240 hasOpenAccess W2000276240 @default.
- W2000276240 hasPrimaryLocation W20002762401 @default.
- W2000276240 hasRelatedWork W1595802699 @default.
- W2000276240 hasRelatedWork W1972126140 @default.
- W2000276240 hasRelatedWork W1982688626 @default.
- W2000276240 hasRelatedWork W2017830665 @default.
- W2000276240 hasRelatedWork W2025146255 @default.
- W2000276240 hasRelatedWork W2075463443 @default.
- W2000276240 hasRelatedWork W2086960639 @default.
- W2000276240 hasRelatedWork W2092341993 @default.
- W2000276240 hasRelatedWork W2419401588 @default.
- W2000276240 hasRelatedWork W4253599722 @default.
- W2000276240 hasVolume "11" @default.
- W2000276240 isParatext "false" @default.
- W2000276240 isRetracted "false" @default.
- W2000276240 magId "2000276240" @default.
- W2000276240 workType "article" @default.