Eur J Anat, 13 (1): 1-6 (2009)

Immunocytochemical evidence for the coexistence of aromatase P450 and estrogen receptor ? in the pituitary gland of the adult male rat

Carretero J., Hernandez R., Tapia M., Prieto D., Carretero M., Gutierrez S., Gonzalez R., Basco M., Gonzalez L., Herrero J.J., Rubio M., Blanco E., Vazquez R.

Department of Human Anatomy and Histology, Institute of Neurosciences of Castilla Y León, University of Salamanca, Spain; Department of Informatics, School of Education, University Pontificia of Salamanca, Spain; Department of Surgery, Faculty of Medicine, University of Salamanca, Spain; Instituto de Neurociencias de Castilla Y León, Facultad de Medicina, Avda. Alfonso X el Sabio s/n, E-37007 Salamanca, Spain

ABSTRACT In previous studies we demonstrated the immunocytochemical expression of aromatase in rat pituitary cells. The aim of the present study is to demonstrate the synthesis of the enzyme through the expression of the mRNA of the enzyme in pituitary cells by in situ hybridization and the relationship between the immunocytochemical expression of aromatase and estrogen receptor ? in adult male rats. In situ hybridization revealed that aromatase-mRNA is located in the cytoplasm of 41% of pituitary cells. By immunocytochemistry, different patterns of reaction for aromatase were found. Moreover, using immunocytochemistry and RT-PCR, all aromatase-positive tumors proved be estrogen receptor ?-positive tumors. The immunocytochemical coexistence of aromatase and estrogen receptor ? was found. These observations demonstrate the synthesis of aromatase in the pituitary gland and its functional ability to develop its estrogenic effects mediated by estrogen receptor ?.

Keywords: aromatase, estrogen receptor alpha, animal cell, animal tissue, article, controlled study, enzyme activity, enzyme synthesis, hypophysis, hypophysis cell, immunocytochemistry, in situ hybridization, male, nonhuman, rat, reverse transcription polymerase chain reaction