Alpha and Luteinizing Hormone Beta Subunit Messenger Ribonucleic Acids During the Rat Estrous Cycle

Abstract

Alpha and LH beta subunit mRNAs were measured in pituitaries of 4-day cycling rats during the estrous cycle. A two-fold increase in alpha mRNA occurred between 0800-2000 h on diestrus, but alpha mRNA concentrations were stable during other days of the cycle. LH beta mRNA concentrations were low during estrus and metestrus (11-16 pg cDNA bound/100 micrograms pituitary DNA), but were elevated (27-30 pg) between 0800-2000 h on diestrus. A second increase in LH beta mRNA was observed on the afternoon of proestrus, prior to the onset of the LH surge with maximum values (45 pg) coincident with peak LH secretion. LH beta mRNA concentrations declined rapidly and had fallen to basal values by midnight on proestrus. These data show that alpha and LH beta mRNAs change in a similar manner during metestrus, diestrus and estrus, suggesting coordinate regulation of alpha and LH beta gene expression at these times. During the LH surge, however, LH beta mRNA alone is increased, suggesting that the LH beta gene can be differentially expressed at times when maximum LH secretion is occurring.

c-JUN Dimerization Protein 2 (JDP2) Is a Transcriptional Repressor of Follicle-stimulating Hormone β (FSHβ) and Is Required for Preventing Premature Reproductive Senescence in Female Mice

“…Gonadotrope cells in the anterior pituitary synthesize and secrete luteinizing hormone (LH) 2 and follicle-stimulating hormone (FSH) in response to pulses of hypothalamic gonadotropin-releasing hormone 1 (GNRH), which can be modulated by activin/inhibin and steroid feedback from the gonads. Gonadotropin hormones are heterodimers of a common ␣ subunit and a unique ␤ subunit.…”

“…Gonadotropin hormones are heterodimers of a common ␣ subunit and a unique ␤ subunit. Gonadotropin levels fluctuate 3-4-fold throughout the menstrual or estrous cycle, preceded by changes in the ␤ subunit transcription (1,2). Dysregulation of the tightly controlled gonadotropin levels leads to reproductive pathophysiology.…”

Serum Luteinizing Hormone, Prolactin, and Thyrotropin and Their Pituitary Subunit mRNA Levels during Proestrus in the Syrian Hamster

“…8,9). Furthermore, mRNA levels for LH subunits (a and |i) [7,8], FSH|! [8,10], and Prl [II) fluctuate over the estrous cycle in female rats and ewes.…”

“…Within the last few years, lutein izing hormone-releasing hormone (LHRH) and gonadal ste roid hormones have been shown to regulate translational and Received: December 31, 1990 Accepted after revision: May 28, 1991 postranslational events in the biosynthesis of anterior pituitary hormones of other animals |6 .8,9). Furthermore, mRNA levels for LH subunits (a and |i) [7,8], FSH|! [8,10], and Prl [II) fluctuate over the estrous cycle in female rats and ewes.…”

“…Furthermore, mRNA levels for LH subunits (a and |i) [7,8], FSH|! [8,10], and Prl [II) fluctuate over the estrous cycle in female rats and ewes. Presum ably, this occurs as a result of corresponding fluctuations in the neural and gonadal hormones which have been well documen ted to occur during this cycle [12][13][14][15].…”