while for a long time it has been perceived that neonates and young children do not perceive pain as the adult, this notion had to be corrected on the basis of neurophysiological data and the ontogenisis of the nociceptive system. also, it has been demonstrated conclusively that neonates and the young infant perceive pain at a much lower nociceptive input which is largely due to a still immatur...

introduction: today nano-medicine tries to produce new drugs to reduce the dosage and side effects of their conventional forms. according to the interaction between zinc and opioidergic system activity, this study has investigated the effect of new kind of zinc supplement, nano zinc oxide (nzno), in compared to its conventional form (czno), in presence and absence of opioidergic system activity...

the prognosis of the neoplastic diseases depends not only on the biogenetic characteristics of cancer cells but also on the immunological response of patients, which may influence the biological features of cancer cells themselves as well as the angiogenic processes. moreover, the immune system in vivo is under a physiological psychoneuroendocrine (pne) regulation, mainly mediated by the brain ...

opium is one of the oldest herbal medicines currently used as an analgesic, sedative and antidiarrheal treatment. the effects of opium are principally mediated by the μ -,κ- and δ-opioid receptors. opioid substances consist of all natural and synthetic alkaloids that are derived from opium. most of their effects on gastrointestinal motility and secretion result from suppression of neural activi...

one of the main components of the stress system is hypothalamus- pituitary-adrenal (hpa) axis. acute activation of µ-opioid receptors increases the activity of the hpa axis, leading to release of acth and corticosterone. glucocorticoids can change behaviors, depend on age but there were no evidences about the interaction between age, opioid system and glucocorticoids. in this experiment, effect...

A. The endogenous opioid system and natural reinforcement 1383 B. The endogenous opioid system and drugs of abuse 1387 C. Perspectives: extending studies to animal models of drug addiction 1393 IV. Genetic Manipulation of the Opioid System, Reinforcement, and Drug Dependence 1393 A. Opioid receptor knockout mice 1393 B. Opioid peptide knockout mice 1394 C. Conclusion 1395 D. Perspectives: towar...

background: opioid drugs are the most effective drugs for the treatment of moderate to severe pain. rates of opioid use are influenced by a variety of factors. the aim of this study was to determine the pattern of use of parenteral opioid drugs in hospitalized patients in a referral teaching hospital. methods: in a retrospective study, required data were extracted from medical records of adult ...

the catastrophic effects of opioids use on public health and the economy are documented clearly in numerous studies. repeated morphine administration can lead to either a decrease (tolerance) or an increase (sensitization) in its behavioral and rewarding effects. morphine-induced sensitization is a major problem and plays an important role in abuse of the opioid drugs. studies reported that mor...

background and objectives cannabinoids which are active compounds of marijuana show some pharmacological effects similar to the opioids. there are also functional interactions between both cannabinoid and opioid systems. in this study we investigated the role of cannabinoid receptors in central amygdala and its interaction with opioid system.   methods in the present study, we investigated the ...

The endogenous opioid system includes three major families of peptides: dynorphins (derived from pre-proenkephalin B), endorphins (derived from pre-proopiomelanocortin), and enkephalins (derived from pre-proenkephalin A). Multiple species of opioid peptides are derived from these major precursors and many of them possess potent cardiovascular properties. Opioid peptides and opioid receptors, of...