Prolactin (PRL) induction of cyclooxygenase 2 (COX2) expression and prostaglandin (PG) production in hamster Leydig cells

作者：Eugenia Matzkin Maria; Ambao Veronica; Herminia Carino Monica; Paola Rossi Soledad; Gonzalez Lorena; Turyn Daniel; Campo Stella; Saul Calandra Ricardo; Beatriz Frungieri Monica

来源：Molecular and Cellular Endocrinology, 2012, 348(1): 33-46.

DOI：10.1016/j.mce.2011.07.029

• Prolactin
• Cyclooxygenase 2
• Prostaglandins
• Leydig cells
• Hamsters

Serum prolactin (PRL) variations play a crucial role in the photoperiodic-induced testicular regression-recrudescence transition in hamsters. We have previously shown that cyclooxygenase 2 (COX2), a key enzyme in the biosynthesis of prostaglandins (PGs), is expressed mostly in Leydig cells of reproductively active hamsters with considerable circulating and pituitary levels of PRL In this study, we describe a stimulatory effect of PRL on COX2/PGs in hamster Leydig cells, which is mediated by IL-1 beta and prevented by P38-MAPK and JAK2 inhibitors. Furthermore, by preparative isoelectric focusing (IEF), we isolated PRL charge analogues from pituitaries of active [isoelectric points (pI): 5.16, 4.61, and 4.34] and regressed (pI: 5.44) hamsters. More acidic PRL charge analogues strongly induced COX2 expression, while less acidic ones had no effect. %26lt;br%26gt;Our studies suggest that PRL induces COX2/PG5 in hamster Leydig cells through IL-1 beta and activation of P38-MAPK and JAK2. PRL microheterogeneity detected in active/inactive hamsters may be responsible for the photoperiodic variations of COX2 expression in Leydig cells.

• 出版日期2012-1-2