Abstract

The nature of the inhibitory action of mammalian prolactin on the development of bullfrog tadpoles was investigated. Tadpoles injected ip with 20 μg of thyroxine (T4) and 2 or 4 mg of ovine prolactin (NIH-P-S-7) underwent metamorphic changes in parallel with T4-injected controls. By contrast, tadpoles injected with 4 IU of bovine thyrotropic hormone (TSH) and either 4.0 or 0.4 mg of prolactin entered into developmental stasis after showing early signs of metamorphic climax, while TSH-injected controlscontrols completed the various metamorphic steps, including tail resorption. Histological examination of the thyroids of animals treated with both TSH and prolactin revealed an extremely high degree of hypertrophy and hyperplasia, with more pronounced depletion of the colloid than in TSH-injected controls. It is concluded that in these experiments prolactin acts at the level of the thyroid and that it has goitrogenic properties. (Endocrinology 81: 748, 1967)

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.