Endocrinology, Vol 117, 2392-2396, Copyright © 1985 by Endocrine Society

ARTICLES

Estrogen decreases rat hypothalamic proopiomelanocortin messenger ribonucleic acid levels

JN Wilcox and JL Roberts

Ovariectomy and estrogen (E) or E plus progesterone treatment has previously been shown to alter both hypothalamic content and portal plasma levels of beta-endorphin. To determine if these changes were accompanied by changes in beta-endorphin synthesis, we used a RNA dot blot method to quantify proopiomelanocortin (POMC) mRNA levels in the arcuate nucleus-median eminence region of rats. Animals were bilaterally ovariectomized, implanted with Silastic capsules containing E or oil, and killed 1 or 3 days after implantation. Total nucleic acid was isolated from dissections of the arcuate-median eminence by proteinase-K/sodium dodecyl sulfate/phenol extraction, and POMC mRNA was quantified by dot blot analysis. Although 1 day of E treatment had no effect on hypothalamic POMC mRNA levels, 3 days of E treatment caused a significant reduction of approximately 40% of POMC mRNA levels relative to oil controls in two replicate experiments. These results suggest that the decreases in hypothalamic POMC peptide levels after E administration reported previously may be due to a decrease in POMC peptide biosynthesis resulting from a decrease in hypothalamic POMC mRNA.

This article has been cited by other articles:

				C. D. Foradori, R. L. Goodman, V. L. Adams, M. Valent, and M. N. Lehman Progesterone Increases Dynorphin A Concentrations in Cerebrospinal Fluid and Preprodynorphin Messenger Ribonucleic Acid Levels in a Subset of Dynorphin Neurons in the Sheep Endocrinology, April 1, 2005; 146(4): 1835 - 1842. [Abstract] [Full Text] [PDF]

				R. H. Mills, R. K. Sohn, and P. E Micevych Estrogen-Induced {micro}-Opioid Receptor Internalization in the Medial Preoptic Nucleus Is Mediated via Neuropeptide Y-Y1 Receptor Activation in the Arcuate Nucleus of Female Rats J. Neurosci., January 28, 2004; 24(4): 947 - 955. [Abstract] [Full Text] [PDF]

				S. Bouret, V. Prevot, D. Croix, A. Howard, E. Habert-Ortoli, S. Jegou, H. Vaudry, J.-C. Beauvillain, and V. Mitchell Expression of GalR1 and GalR2 Galanin Receptor Messenger Ribonucleic Acid in Proopiomelanocortin Neurons of the Rat Arcuate Nucleus: Effect of Testosterone Endocrinology, May 1, 2000; 141(5): 1780 - 1794. [Abstract] [Full Text] [PDF]

				B. N. Roy, R. L. Reid, and D. A. Van Vugt The Effects of Estrogen and Progesterone on Corticotropin-Releasing Hormone and Arginine Vasopressin Messenger Ribonucleic Acid Levels in the Paraventricular Nucleus and Supraoptic Nucleus of the Rhesus Monkey Endocrinology, May 1, 1999; 140(5): 2191 - 2198. [Abstract] [Full Text]

				Y. R. Smith, J.-K. Zubieta, M. G. del Carmen, R. F. Dannals, H. T. Ravert, H. A. Zacur, and J. J. Frost Brain Opioid Receptor Measurements by Positron Emission Tomography in Normal Cycling Women: Relationship to Luteinizing Hormone Pulsatility and Gonadal Steroid Hormones J. Clin. Endocrinol. Metab., December 1, 1998; 83(12): 4498 - 4505. [Abstract] [Full Text]

				A. E. Herbison Multimodal Influence of Estrogen upon Gonadotropin-Releasing Hormone Neurons Endocr. Rev., June 1, 1998; 19(3): 302 - 330. [Abstract] [Full Text]

				J. D. Graham and C. L. Clarke Physiological Action of Progesterone in Target Tissues Endocr. Rev., August 1, 1997; 18(4): 502 - 519. [Abstract] [Full Text] [PDF]

				S. Mani, J. Allen, J. Clark, J. Blaustein, and B. O'Malley Convergent pathways for steroid hormone- and neurotransmitter-induced rat sexual behavior Science, August 26, 1994; 265(5176): 1246 - 1249. [Abstract] [PDF]