The analgesic effects of leukocyte-derived opioids have been exclusively demonstrated for
somatic inflammatory pain, for example, the pain associated with surgery and arthritis …

Ability to perceive physiological pain is essential in protecting the individual from tissue
destruction. In contrast, pathological chronic pain is an expression of maladaptive alterations …

In peripheral inflamed tissue interactions between leukocyte-derived opioid peptides and
opioid receptors on sensory neurons lead to potent, clinically relevant inhibition of pain …

Classically, pain sensation or suppression has been attributed exclusively to neuronal
circuits. This review challenges this notion and presents an expanded concept about the …

This review summarizes recent findings on neuro-immune mechanisms underlying opioid-
mediated inhibition of pain. The focus is on events occurring in peripheral injured tissues …

Neuropathic pain is a debilitating consequence of nerve injuries and is frequently resistant
to classical therapies. T lymphocytes mediate adaptive immune responses and have been …

It is accepted that inflammatory mediators released from leukocytes contribute to the
generation of pain. However, it is less well known that immune cells also produce mediators …

Recent findings have suggested a significant involvement of the immune system in the
control of pain. Immune cells contain opioid peptides that are released within inflamed tissue …

It is recently become clear that activated immune cells and immune-like glial cells can
dramatically alter neuronal function. By increasing neuronal excitability, these non-neuronal …

Opioid receptors are widely expressed in the central and peripheral nervous system as well
as in numerous nonneuronal tissues. Both animal models and human clinical data support …