Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 1985 Mar;40(3):238-45.
doi: 10.1159/000124080.

Effects of progesterone on hypothalamic and plasma LHRH

Comparative Study

Effects of progesterone on hypothalamic and plasma LHRH

J C Peduto et al. Neuroendocrinology. 1985 Mar.

Abstract

The hypothalamic action of progesterone on the regulation of LH secretion was investigated in a rat model ideally suited for the study of progesterone effects under conditions in which the animal is sensitive to progesterone but does not have an estrogen-induced gonadotropin surge. Immature female rats were ovariectomized at 26 days of age and treated for 4 days with a subphysiological dose of 0.1 microgram/kg/day estradiol followed by the injection of either 0.8 or 3.2 mg/kg progesterone at 9.30 a.m. on day 5. Serum LH levels were significantly depressed below control and pretreatment values 30 min after either dose of progesterone. At this time, 0.8 mg/kg progesterone administration resulted in a significant increase in MBH-LHRH and plasma LHRH levels. In contrast, the administration of the 3.2 mg/kg dose of progesterone did not result in an increase in MBH-LHRH levels. By 2 p.m., rats receiving 0.8 mg/kg progesterone, but not those receiving 3.2 mg/kg progesterone, showed a significant increase in serum LH concentration and this elevation was maintained at 4 p.m. The increase in serum LH levels was preceded by a rise in MBH-LHRH levels by 1 p.m., followed by a fall at 2 p.m. The LH rise was maintained during the rise and replenishment of the MBH-LHRH by 3 p.m. Between 2 and 3 p.m. the replenishment of MBH-LHRH levels was accompanied by a fall in POA-LHRH levels.(ABSTRACT TRUNCATED AT 250 WORDS)

PubMed Disclaimer

Publication types

LinkOut - more resources