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Study · Measured the body's own peptide · 1980

5 results

Levels of neurohypophyseal peptides in the rat during the first month of life. I. Basal levels in plasma, pituitary, and hypothalamus.

Sinding C, Seif SM, Robinson AG

Endocrinology1 Sept 1980Cited by 21 (Europe PMC)

PMID7398579 (opens in a new tab)DOI10.1210/endo-107-3-749 (opens in a new tab)PepBankPUB-07398579
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 study5

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

Natural levels measured3

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 newborn rats, pituitary oxytocin was less than 1% of the adult value.

    In plain wordsIn newborn rats, the body's own pituitary oxytocin was less than 1% of the adult value.

    Peptide
    Oxytocin
    Outcome
    DecreasePituitary oxytocin amount at birth
    Study

    ratn: not reported in source

    pituitary
    Comparator
    adult pituitary oxytocin
    Outcome group
    Hormone levels · Endocrine and hormones

    Source sentences

    Summary
    The three peptides were present in the pituitary at birth, but in amounts less than 1% of the adult level.
    1 context sentence
    Summary · context
    Vasopressin, oxytocin, and neurophysin were measured by RIA in the pituitary, hypothalamus, and plasma (except oxytocin) of the rat during the first month of life.

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

  2. 02AnimalEndogenous levelAnimal study (in vivo)Other

    In rats, pituitary oxytocin remained low through day 8 after birth and increased from days 8 to 21.

    In plain wordsIn rats, the body's own pituitary oxytocin stayed low through day 8 after birth, then increased to day 21.

    Peptide
    Oxytocin
    Outcome
    IncreasePostnatal pituitary oxytocin level
    Study

    ratn: not reported in source

    pituitary
    Outcome group
    Hormone levels · Endocrine and hormones

    Source sentences

    Summary
    The vasopressin content of the pituitary increased rapidly in the first days after birth, while the levels of oxytocin and neurophysin remained low until 8 days and then increased between 8-21 days.
    1 context sentence
    Summary · context
    Vasopressin, oxytocin, and neurophysin were measured by RIA in the pituitary, hypothalamus, and plasma (except oxytocin) of the rat during the first month of life.

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

  3. 03AnimalEndogenous levelAnimal study (in vivo)Other

    In rats, the vasopressin-to-oxytocin ratio decreased from 4.4 at birth to unity at day 30.

    In plain wordsIn rats, the ratio of the body's own vasopressin to oxytocin fell from 4.4 at birth to 1 at day 30.

    Peptide
    Oxytocin
    Outcome
    DecreasePituitary vasopressin-to-oxytocin ratio
    Study

    ratn: not reported in source

    pituitary
    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Source sentences

    Summary
    The ratio of vasopressin to oxytocin in the pituitary was 4.4 at birth and reached unity (the ratio in the adult) at 30 days.
    1 context sentence
    Summary · context
    Vasopressin, oxytocin, and neurophysin were measured by RIA in the pituitary, hypothalamus, and plasma (except oxytocin) of the rat during the first month of life.

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

Studies that did not test the peptide alone2

In this study, Oxytocin was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking Oxytocin.

  1. 04AnimalNot a test of Oxytocin aloneAnimal study (in vivo)Other

    In rats, the neurophysin-to-hormone ratio for pooled oxytocin and vasopressin reached unity at 21-30 days.

    In plain wordsIn rats, the neurophysin ratio to pooled natural oxytocin and vasopressin reached 1 at 21-30 days.

    Peptide
    Oxytocin
    Outcome
    IncreasePituitary neurophysin-to-hormone ratio
    Study

    ratn: not reported in source

    pituitary
    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Source sentences

    Summary
    The ratio of neurophysin to hormone reached unity at 21-30 days.
    1 context sentence
    Summary · context
    At birth, the moles of neurophysin in the pituitary relative to the moles of hormone (oxytocin plus vasopressin) was low (0.15), largely due to a molar excess of vasopressin.

    In this study, Oxytocin was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Oxytocin.

  2. 05AnimalNot a test of Oxytocin aloneAnimal study (in vivo)Other

    In rats at birth, the pituitary neurophysin-to-hormone ratio for pooled oxytocin and vasopressin was low (0.15), largely because of a molar excess of vasopressin.

    In plain wordsIn newborn rats, the neurophysin ratio to pooled natural oxytocin and vasopressin was low (0.15).

    Peptide
    Oxytocin
    Outcome
    Not applicablePituitary neurophysin-to-hormone ratio at birth
    Study

    ratn: not reported in source

    pituitary
    Outcome group
    Endogenous peptide levels · Endocrine and hormones

    Source sentences

    Summary
    At birth, the moles of neurophysin in the pituitary relative to the moles of hormone (oxytocin plus vasopressin) was low (0.15), largely due to a molar excess of vasopressin.

    In this study, Oxytocin was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking Oxytocin.

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

    12 Oct 2026, 11:11 UTC

    Study results updated

  2. Version 1

    9 Oct 2026, 02:53 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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