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Horm Metab Res 2002; 34(8): 431-434
DOI: 10.1055/s-2002-33600
Original Basic

© Georg Thieme Verlag Stuttgart · New York

Effects of Dietary Cholesterol on Pyroglutamyl Aminopeptidase Activity in Mouse Frontal Cortex, Pituitary, and Adrenal Glands

M.  J.  Ramírez-Expósito 1 , M.  J.  García 1 , M.  D.  Mayas 1 , M.  P.  Carrera 1 , G.  K.  Tsuboyama 2 , J.  M.  Martínez-Martos 1
  • 1Unit of Physiology, Department of Health Sciences, Faculty of Experimental and Health Sciences, University of Jaén, Spain
  • 2Department of Psychiatry, The New York Hospital-Cornell Medical Center, Westchester Division, New York, USA
Further Information

Publication History

Received: 13 February 2002

Accepted after revision: 18 April 2002

Publication Date:
25 September 2002 (online)

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Abstract

Pyroglutamyl aminopeptidase (pGluAP) is an omega peptidase that hydrolyzes biologically active peptides, such as thyrotropin-releasing hormone (TRH), with neuronal and extraendocrine functions. We analyzed the effects of a cholesterol-enriched diet on soluble and membrane-bound pGluAP activity in frontal cortex, pituitary and adrenal glands of male and female mice using fluorimetric assays. Significant increases were observed in soluble pGluAP activity in the frontal cortex and adrenal glands in males and in the pituitary in females. Membrane-bound pGluAP activity was increased in the frontal cortex and pituitary of males and females after the mice were fed a cholesterol-enriched diet. These increases may produce changes in the metabolism of endogenous substrates, including TRH, which may be related to alterations in its neuromodulator functions and to the possible relationship between TRH and other neurotransmitter systems.

Key words

Thyrotropin-Releasing Hormone Degrading Ectoenzyme - Dietary Lipids - Sex Differences - Pyrrolidon Carboxypeptidase

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Dr. J. M. Martínez-Martos

Unit of Physiology · Faculty of Experimental and Health Sciences · University of Jaén, Paraje “Las Lagunillas” s/n

23071 Jaén · Spain ·

Phone: + 34 (953) 00 26 00

Fax: + 34 (953) 01 21 41

Email: jmmartos@ujaen.es