Prostaglandin E2 receptor subtypes, EP1, EP2, EP3 and EP4 in human and mouse ocular tissues -: a comparative immunohistochemical study

The purpose of the present study was to compare the localization of prostaglandin E-2 receptor subtypes in normal human and mouse ocular tissues. Paraffin embedded sections of normal human and mouse (129 Sv/Ev) eyes were treated with EP1, EP2, EP3 and EP4 specific antibodies and subsequently incubated with Alexa Fluor secondary antibody (Ex/Em = 555/571) to detect the presence of EP receptor proteins. Fluorescence of the localized antibodies was visualized in a Carl Zeiss Microscope (Axiovert 200) and photographed using Carl Zeiss Axiocam camera. In mice EP, and EP3 receptor subtypes were only moderately expressed, EP3 receptor expression being almost negligible. In human cornea and iris ciliary body, EP1 and EP3 receptors were prominently expressed. EP4 receptor was expressed moderately in human and mouse ocular tissues. EP2 receptor was the most prominently and abundantly expressed receptor in both human and mouse ocular tissues. It is concluded that the pattern of the distribution of EP receptor subtypes in the ocular tissues are similar in human and mouse. Thus, 129 Sv/Ev strains of mice would make an appropriate animal model for studying the ocular pathophysiological roles of prostaglandin receptor agonists. (C) 2004 Elsevier Ltd. All rights reserved.