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Study · Measured the body's own peptide · 1984

4 results

Circadian variation of DSIP-like material in rat plasma.

Fischman AJ, Kastin AJ, Graf MV

Life sciences1 Nov 1984Cited by 5 (Europe PMC)

PMID6548540 (opens in a new tab)DOI10.1016/0024-3205(84)90566-6 (opens in a new tab)PepBankPUB-06548540
Publisher pagePubMedAsk about this study
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Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study4

No result from this study comes from a test of the peptide.

Natural levels measured4

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

  1. 01AnimalEndogenous levelAnimal study (in vivo)Other

    In rats, plasma DSIP-like immunoreactivity showed a circadian rhythm that paralleled the rhythm of corticosterone.

    In plain wordsIn rats, the body's own DSIP-like material in blood rose and fell over the day, in step with corticosterone.

    Peptide
    Delta sleep-inducing peptide (DSIP)
    Outcome
    Not applicableCircadian rhythm of plasma DSIP-like immunoreactivity
    Study

    ratn: not reported in source

    rat plasma, radioimmunoassay
    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Source sentences

    Summary
    Levels of delta-sleep-inducing peptide-like immunoreactivity (DSIP-LI) in rat plasma were measured by radioimmunoassay and found to exhibit a circadian rhythm that parallelled the normal rhythm for corticosterone
    1 context sentence
    Summary · context
    Levels of delta-sleep-inducing peptide-like immunoreactivity (DSIP-LI) in rat plasma were measured by radioimmunoassay and found to exhibit a circadian rhythm that parallelled the normal rhythm for corticosterone.

    This result measures the body's own Delta sleep-inducing peptide (DSIP). Nobody was given the peptide. It is not evidence about taking it.

  2. 02AnimalEndogenous levelAnimal study (in vivo)Other

    In rats, maximal plasma levels of DSIP-LI occurred at about 1700 h.

    In plain wordsIn rats, the body's own DSIP-like material in blood peaked in the late afternoon.

    Peptide
    Delta sleep-inducing peptide (DSIP)
    Outcome
    Not applicableTime of maximal plasma DSIP-LI
    Study

    ratn: not reported in source

    rat plasma, radioimmunoassay
    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Measurements

    Time of maximal level
    1700 h
    plasma DSIP-LI and corticosterone

    Source sentences

    Summary
    The maximal plasma levels of both substances were observed to occur at about 1700h.
    1 context sentence
    Summary · context
    Levels of delta-sleep-inducing peptide-like immunoreactivity (DSIP-LI) in rat plasma were measured by radioimmunoassay and found to exhibit a circadian rhythm that parallelled the normal rhythm for corticosterone.

    This result measures the body's own Delta sleep-inducing peptide (DSIP). Nobody was given the peptide. It is not evidence about taking it.

  3. 03AnimalEndogenous levelAnimal study (in vivo)Other

    In rats, the lowest plasma DSIP-LI concentration occurred at 2400 h.

    In plain wordsIn rats, the body's own DSIP-like material in blood was lowest at midnight.

    Peptide
    Delta sleep-inducing peptide (DSIP)
    Outcome
    Not applicableTime of lowest plasma DSIP-LI
    Study

    ratn: not reported in source

    rat plasma, radioimmunoassay
    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Measurements

    Time of lowest level
    2400 h
    plasma DSIP-LI

    Source sentences

    Summary
    The lowest concentrations of DSIP-LI and corticosterone were detected at 2400h and 1000h, respectively.
    1 context sentence
    Summary · context
    Levels of delta-sleep-inducing peptide-like immunoreactivity (DSIP-LI) in rat plasma were measured by radioimmunoassay and found to exhibit a circadian rhythm that parallelled the normal rhythm for corticosterone.

    This result measures the body's own Delta sleep-inducing peptide (DSIP). Nobody was given the peptide. It is not evidence about taking it.

  4. 04AnimalEndogenous levelAnimal study (in vivo)Other

    In rats, exposure to constant illumination abolished the plasma DSIP-LI rhythm.

    In plain wordsIn rats, constant light removed the daily rhythm of the body's own DSIP-like material in blood.

    Peptide
    Delta sleep-inducing peptide (DSIP)
    Outcome
    DecreaseEffect of constant illumination on plasma DSIP-LI rhythm
    Study

    ratn: not reported in source

    rat plasma, radioimmunoassay
    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Source sentences

    Summary
    Exposure to constant levels of illumination abolished the rhythm of DSIP-LI.
    1 context sentence
    Summary · context
    Levels of delta-sleep-inducing peptide-like immunoreactivity (DSIP-LI) in rat plasma were measured by radioimmunoassay and found to exhibit a circadian rhythm that parallelled the normal rhythm for corticosterone.

    This result measures the body's own Delta sleep-inducing peptide (DSIP). Nobody was given the peptide. It is not evidence about taking it.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    10 Oct 2026, 09:43 UTC

    Study results updated

  2. Version 1

    9 Oct 2026, 03:04 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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