Expression and Localization of Opioid Receptors in Male Germ Cells and the Implication for Mouse Spermatogenesis

Abstract

The presence of endogenous opioid peptides in different testicular cell types has been extensively characterized and provides evidence for the participation of the opioid system in the regulation of testicular function. However, the exact role of the opioid system during the spermatogenesis has remained controversial since the presence of the mu-, delta- and kappa-opioid receptors in spermatogenic cells was yet to be demonstrated. Through a combination of quantitative real-time PCR, immunofluorescence, immunohistochemistry and flow cytometry approaches, we report for the first time the presence of active mu-, delta- and kappa-opioid receptors in mouse male germ cells. They show an exposition time-dependent response to opioid agonist, hence suggesting their active involvement in spermatogenesis. Our results contribute to understanding the role of the opioid receptors in the spermatogenesis and could help to develop new strategies to employ the opioid system as a biochemical tool for the diagnosis and treatment of male infertility.

POMC: The Physiological Power of Hormone Processing

“…-Opioid receptors are expressed centrally in regions including the cortex, hippocampus, hypothalamus, and brain stem (292,293,301) and are widely expressed in peripherally tissues including pancreas (421), testis (126,432), ovary (432), and kidney (432). These receptors not only mediate analgesic effects, but can also play a role in the regulation of feeding behavior (as described below).…”

Mitragynine, an euphoric compound inhibits hERG1a/1b channel current and upregulates the complexation of hERG1a-Hsp90 in HEK293-hERG1a/1b cells

“…For each test sample, at least 20 cells were randomly selected from the 15 spots for quantitation. The green fluorescence intensity was quantified using ImageJ software (http://imagej.nih.gov/ij/) 72,73 . Intensity was represented as the “corrected total cell fluorescence” (CTCF) per area using the equation “CTCF/area = [Integrated density - (Area of selected cell × Mean fluorescence of background readings)]/Area of selected cell”.…”

Synergistic role of 5-azacytidine and ascorbic acid in directing cardiosphere derived cells to cardiomyocytes in vitro by downregulating Wnt signaling pathway via phosphorylation of β-catenin

“…Immunofluorescence analysis of control, Aza and Aza+AA treatment groups was performed as described above to check the difference in the expression levels of the following primary antibodies: CD 105, Nkx 2.5, GATA 4 and α-Sarcomeric actinin. To quantify the level of expression among control, Aza and Aza+AA treated CDCs, corrected total cell fluorescence (CTCF) of the cells was calculated using Image J software [ 26 , 30 ]. Formula for CTCF was as follows: CTCF/μm 2 = [Integrated density–(area of selected cell x mean fluorescence of background readings)] / Area of selected cell.…”