Abstract

Rat hepatic prolactin receptor is regulated by sex steroids. A high level of the receptor was found in female rats but the level was nearly undetectable in males. Gonadectomy reduced the receptor level in females but increased the level in males. Administration of estradiol benzoate (0.05 μmoles/kg on alternate days subcutaneously for 9 days) to adult gonadectomized females increased the receptor level by 473% whereas the same treatment in adult gonadectomized males produced a more modest 276% increase. This sexually dimorphic pattern in the responsiveness to estrogen stimulation in adult rats appeared to be determined neonatally. Neonatal gonadectomy of male rats changed the hepatic response system to a more female pattern in adulthood. Replacement of testosterone (1.45 μmoles at days 1 and 3 after birth) to these neonatally gonadectomized male rats restored the male pattern. Diethylstilbestrol replacement (1.45μmoles at days 1 and 3 after birth) to the neonatally gonadectomized male rats showed the same effect as neonatally administered testosterone. Scatchard analysis revealed that the observed changes in binding are related to changes in binding capacity but not affinity. Desaturation by 4 M MgCl 2 indicated that the amount of endogenously bound hormone was negligible in our membrane preparations.

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.