Background Opioid receptors and endogenous opioid peptides act not merely in the control of nociceptive pathways, indeed many reports demonstrate the consequences of opiates in sperm cell motility and morphology suggesting the need for these receptors in the modulation of reproduction in mammals. delta opioid receptor is certainly expressed being a doublet of 65 and… Continue reading Background Opioid receptors and endogenous opioid peptides act not merely in