Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Prolactin response to metoclopramide in hyperthyroidism.

J S Sawers, H A Kellett, N S Brown

    The Journal of Clinical Endocrinology and Metabolism
    |July 1, 1982
    PubMed
    Summary
    This summary is machine-generated.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    Thyroid hormone replacement - a counterblast to guidelines.

    The journal of the Royal College of Physicians of Edinburgh·2018
    Same author

    Reductions in lipids and CV risk markers in patients with type 2 diabetes treated with liraglutide: a meta-analysis.

    Canadian journal of diabetes·2015
    Same author

    Precision large field scanning system for high numerical aperture lenses and application to femtosecond micromachining of ophthalmic materials.

    The Review of scientific instruments·2014
    Same author

    Botulinum toxin-what urologic uses does the data support?

    Current urology reports·2013
    Same author

    Weight change with liraglutide and comparator therapies: an analysis of seven phase 3 trials from the liraglutide diabetes development programme.

    Diabetes, obesity & metabolism·2012
    Same author

    Cell migration and the boyden chamber.

    Methods in molecular medicine·2011

    Hyperthyroidism blunts the prolactin (PRL) response to metoclopramide, a dopamine blocker. This suggests thyroid hormones directly inhibit pituitary PRL release, not just via hypothalamic dopamine.

    Area of Science:

    • Endocrinology
    • Neuroendocrinology
    • Reproductive Endocrinology

    Background:

    • Thyroid hormones influence pituitary hormone secretion.
    • Dopamine is known to inhibit prolactin (PRL) release.
    • Previous research suggested thyroid hormones stimulate hypothalamic dopamine secretion to inhibit PRL.

    Purpose of the Study:

    • To investigate the effect of hyperthyroidism on prolactin (PRL) and thyroid-stimulating hormone (TSH) response to metoclopramide.
    • To determine if thyroid hormones directly inhibit PRL release at the anterior pituitary level.

    Main Methods:

    • Oral administration of metoclopramide, a dopamine receptor antagonist, to hyperthyroid and euthyroid subjects.
    • Measurement of PRL and TSH levels before and after metoclopramide administration.

    Related Experiment Videos

  • Assessment of the effect of metoclopramide on TRH-induced PRL and TSH release.

    • Main Results:

    • Metoclopramide significantly increased PRL levels in both hyperthyroid and euthyroid groups.
    • The PRL increase at 120 minutes was significantly lower in hyperthyroid subjects compared to euthyroid controls.
    • Metoclopramide did not restore normal PRL or TSH responsiveness to TRH in hyperthyroid patients.

    Conclusions:

    • Elevated thyroid hormone levels appear to directly inhibit PRL release at the anterior pituitary.
    • The findings challenge the sole reliance on hypothalamic dopamine stimulation for thyroid hormone's PRL inhibitory effect.
    • Hyperthyroidism impairs the pituitary's response to dopaminergic blockade, indicating a direct pituitary-level effect.