No description available.

The major aim of the experiments described in this thesis was to investigate the putative mechanisms that are involved in the control of B- endorphin (B-END) secretion into the peripheral blood of the Soay ram. In addition, the effect of 8-END and adrenocorticotrophin (ACTE1) on cortisol secretion was investigated. A series of experiments was carried out to assess the influence of season, photoperiod, melatonin implantation, pinealectomy, castration and testosterone replacement on B-END secretion. There were significant changes in the plasma concentrations of B-END related to season and photoperiod in rams kept outside and inside, respectively. In outdoor rams B-END levels were highest in autumn and lowest in winter; in indoor rams the levels were highest during short days and lowest during long days. Melatonin implantation in outdoor rams from May to August caused a significant increase in B-END secretion, indicating a melatonin-induced short-day effect inspite of the prevailing long days. Pinealectomy disrupted the seasonal cycle in B-END secretion. Castration and testostrone replacement in indoor rams did not influence B-END secretion. These results indicate that B-END secretion is strongly influenced by season and photoperiod (via melatonin from the pineal gland) and that testosterone plays no role in B-END secretion. In another series of experiments, the roles of arginine vasopressin (AVP), corticotrophin releasing factor (CRF), the synthetic glucocorticoid, dexamethasone (DEX) and the synthetic glucocorticoid antagonist, RU 486, in the control of the seasonal cycle in B-END secretion were investigated in spring, summer, autumn and winter. AVP and CRF given alone or in combination significantly stimulated 8-END secretion at all seasons and acted synergistically when given together. The responses were greater in summer and autumn than in winter and spring. DEX suppressed 8-END secretion at all seasons and the responses were also greater in summer and autumn. DEX also blocked the AVP-induced increase in 8-END secretion, indicating an action of DEX at the pituitary gland. RU 486 given in summer and winter significantly stimulated 8-END secretion only in winter, indicating a seasonal variation in the negative feedback action of endogenous glucocorticoids. In addition, ACTH, but not 8-END, significantly stimulated cortisol secretion at all seasons, with the greatest response in spring. These studies indicate that AVP, CRF and glucocorticoids are involved in the control of the seasonal cycle in 8-END secretion; and that ACTH rather than 8-END constitutes the " drive " to cortisol secretion. The roles of dopamine (DA) and endogenous opioid peptides (EOP) in the control of 8-END secretion were also investigated. The mixed DA antagonist, pimozide, significantly increased 8-END secretion under long and short days; with a greater effect under long days. The D2 agonist, bromocriptine, and the D2 antagonist, sulpiride, significantly decreased and increased, respectively, 8-END secretion both under long and short days. The opioid antagonist, naloxone, had no effect on 8-END secretion. These studies indicate that DA exerts an inhibitory control over 8-END secretion while the EOP play no role in 8-END secretion. Based on the current results and a survey of the relevant literature, a model is proposed in which AVP, CRF, glucocorticoids on one hand, and DA on the other hand, are involved in the control of the secretory activity of corticotrophs and melanotrophs in the pituitary gland. These central mechanisms are influenced by changes in photoperiod and other environmental factors to dictate the seasonal cycle in 6-END secretion in the Soay ram, which is low in winter and high in autumn. To fully assess the importance of AVP, CRF and DA in the seasonal control of 6-END secretion, it will be necessary to directly measure the concentration of these hormones in the hypophysial portal circulation of Soay rams at different seasons.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.

The purpose of this study was to investigate natural killer cell activity and the possible role of beta- endorphin in a natural model of autoimmune orchitis, the dark mink. An assay was developed to study natural killer cell activity in the mink and base-line levels of activity in this specie were determined. Natural killer cell activity was assessed in fertile mutation mink, primary infertile dark mink and secondary infertile Utah dark mink with autoimmune orchitis. The study included three sampling times: November, March and April. Natural killer cell activity was significantly lower in mink studied in April than it was in. mink studied in March or November, and there was a significant correlation of activity to fertility. The addition of beta-endorphin to natural killer cell cultures had no effect on activity. A preliminary study was done to determine concentration levels of beta-endorphin in mink plasma, pituitary, hypothalamus and testes. Measurable amounts were found in all tissue types studied. Although the number of samples was too limited to draw significant conclusions, there appears to be a trend toward lower beta-endorphin concentration, in pituitary tissue and plasma samples, of mink with autoimmune orchitis. Beta-endorphin levels did not appear to correlate with natural killer cell activity in the mink. Two assays, the natural killer assay and the blasto-genesis assay, were used to insure that the beta-endorphin preparation used in this study were active. Natural killer cell activity had been reported to be enhanced by the addition of beta-endorphin. In the present study natural killer cell activity of human peripheral blood mononuclear cells (PBMC) was enhanced in the presence of betaendorphin, suggesting that the peptide was active. In addition, the blastogenic response of human PBMC was enhanced by the addition of beta-endorphin to cultures in the present study.

Schmerz gehört zu den Kardinalsymptomen einer Entzündung. Im Wesentlichen kann die Entstehung von Schmerz am Ort des Entzündungsgeschehens auf das Einwandern (Diapedese) von Leukozyten aus dem peripheren Blut-strom in das Gewebe zurückgeführt werden. Dort findet sowohl die Produktion von Zytokinen und Chemokinen statt, welche weitere Entzündungszellen rekrutieren und die Entzündungsreaktion verstärken, als auch die Freisetzung von Opioidpeptiden, die schmerzlindernd wirken. In Vorarbeiten der Arbeitsgruppe konnte eine Opioidfreisetzung aus neutrophilen Granulozyten nach Stimulation mit bakteriellen Antigenen oder Chemokinen \(in\) \(vitro\) nachgewiesen werden. Diese führen \(in\) \(vivo\) eine Antinozizeption herbei. Für neutrophile Granulozyten wurden der Chemokinrezeptor CXCR1/2 sowie der Formylpep-tidrezeptor als Signal-transmittierende Rezeptoren identifiziert. Über den klassischen Mechanismus der Exozytose gelangt das Beta-Endorphin somit in das Gewebe und interagiert mit Opioidrezeptoren auf primär sensorischen Nervenendigungen. \(in\) \(vivo\) äußerte sich die Freisetzung des Opioidpeptids in einer Anhebung mechanischer Schmerzschwellen, die durch den Opioidrezeptorantagonisten Naloxon aufgehoben werden konnten. Die Bindung, vornehmlich an MOP, führt zur Erniedrigung des cAMP-Spiegels, zur Hyperpolarisation der Nervenzelle und zur Verminderung von Schmerzschwellen. Im Mittelpunkt dieser Arbeit stehen Monozyten als führende Zellpopulation der späten Entzündungsphase. Es sollte untersucht werden, welche Rezeptoren eine Opioidfreisetzung aus Monozyten vermitteln sowie welche intrazellulären Signalwege involviert sind. Humane Monozyten wurden isoliert und \(in\) \(vitro\) mit dem bakteriellen Antigen Lipopolysaccharide (LPS) stimuliert. Dieses steht exemplarisch für mikrobielles Infektgeschehen und Entzündung. In den Zellüberständen wurde mittels ELISA die Beta-Endorphin-Konzentration ermittelt. Weiterhin wurden Opioidgehalt und -freisetzung in der nicht-klassischen CD14+CD16+ Monozytensubpopulation im Vergleich zu klassischen CD14+CD16- Monozyten analysiert. Zur weiteren Aufklärung des Rezeptors, welcher die Opioidfreisetzung vermittelt, wurde der niedermolekulare TLR4-Antagonist TAK-242 genutzt. Wir fanden eine Zunahme der Beta-Endorphin-Freisetzung nach Stimulation mit LPS im Vergleich zur unstimulierten Kontrolle. Eine Zugabe des TLR4-Inhibitors reduzierte die Beta-Endorphin-Freisetzung signifikant. TLR4 agiert somit als PRR für die Opioidfreisetzung aus Monozyten. CD14+CD16+ Monozyten enthalten einen geringeren Anteil an Beta-Endorphin und setzten dementsprechend weniger frei. Ihre Rolle als pro-inflammatorisch und ihre Beteiligung an der Genese inflammatorischer Krankheitsbilder wird dadurch gestützt. Die Signalkaskade, über die diese Freisetzung erfolgt, konnte durch den Einsatz von Rezeptorinhibitoren dahingehend entschlüsselt werden, dass eine Beteiligung des IP3-Rezeptors sowie von intrazellulärem Calcium wichtig ist. Ferner wurde evident, dass auch eine basale Freisetzung existiert, die über denselben Weg verläuft. Durch die Behandlung mit dem TLR4-Antagonisten TAK-242, der die Freisetzung von Beta-Endorphin \(in\) \(vitro\) unterdrückt, wird auch die analgetische Wirkung von LPS \(in\) \(vivo\) aufgehoben. TLR4 Agonisten sind daher potentielle alternative Analgetika, welche die endogene Schmerzkontrolle unterstützen könnten. Jedoch fließen viele Wechselwirkungen wie z.B. proalgetische Wirkungen von TLR4 in das komplexe Gefüge der Immunzellantwort ein. Diese wurden nicht weiter untersucht. Vor einer klinischen Anwendung müssten solche Effekte näher betrachtet werden. / Endogenous opioids from monocytes mediate tonic endogenous antinociception in the late phase of inflammation. Monocytes expressing TLR4 dose-dependently released \(\beta\)-END after stimulation with lipopolysaccharide (LPS) dependent on intracellular calcium. \(in\) \(vitro\) \(\beta\)-endorphin (\(\beta\)-END) content increased during human monocyte differentiation as well as in anti-inflammatory CD14\(^+\)CD16\(^-\) monocytes. Peripheral TLR4 acts as a counter-regulatory mechanism for inflammatory pain \(in\) \(vivo\), and increases the release of opioid peptides from monocytes \(in\) \(vitro\). TLR4 antagonists as new treatments for sepsis and neuropathic pain might unexpectedly enhance pain by impairing peripheral opioid analgesia.

The use of gene-based techniques to produce antinociceptive molecules has been actively investigated for treatment of neuropathic pain and trauma of central nervous system. Among the endogenous opioids, b-endorphin (b-EP) is the most potent one, which is derived from pro-opiomelanocortin (POMC). In addition to b-endorphin, POMC is also the precursor of many neuropeptides such as adrenocorticotropin hormone (ACTH), melanocyte-stimulating hormone (a-MSH), ¡Ketc. Appropriate administration of POMC gene is essential for the success of its clinical application. Thus, gene transfer approach seems to be suitable for continuous supply of b-endorphin to alleviate intractable pain. Recombinant adenovirus was used as gene delivery system for POMC because of its high titer, wide host range, and transduction efficiency. In the present study, we have generated and characterized the recombinant adenovirus encoding POMC (Ad-POMC) by PCR and western blot analysis, and detect the presence of opioid peptides including ACTH, a-MSH and b-EP by RIA and chemilluminiscent assay. GH3 cells infected with Ad-POMC showed significantly higher levels of ACTH, b-endorphin, and a¡VMSH comparing with cells of control groups. By using Ad-GFP, the optimal MOI for adenovirus vector to infect neuronal GH3 cells, glial C6 cells, hepatoma Hep3B cells, smooth muscle G8 cells, fibroblast CCD-965K cells, and endothelial EA.hy926 cells was determined at 50, 500, 50, 500, 500, and 200, respectively. The results of determining the efficiency of POMC processing in different types of cells after in vitro cell cultures gene delivery indicated that peripheral cells, though at a lower extent, are capable of cleaving POMC and releasing opioid peptides after POMC gene delivery like neuronal cells of central nervous system. In formalin test, the intrathecal POMC gene delivery significantly decreased the magnitude of the formalin-evoked flinching response phase 1 (P < 0.05) and phase 2 (P < 0.001) when compared with rats receiving saline or Ad-GFP. In conclusion, the intrathecal POMC gene delivery can produce effectively attenuation on the inflammatory pain response. So far, there have been various gene delivery studies confirming the potential role of POMC in antinociception. In the future, more experiments will be needed to characterize the effects of POMC expression on cellular lipid metabolism. This will enable us to evaluate the therapeutic potential of POMC on treatment of obesity.

No description available.

Labor may perhaps be the most painful a woman might experience, although characterized by large inter-individual variability. The perceived pain during labor is the result of diverse factors, i.e. her previous pain experiences, the analgesia she receives and maybe also her genes. The overall aim of this thesis was to investigate biological and psychological mechanisms underlying inter-individual differences in labor pain related behaviors. The mechanisms that characterize endogenous pain relief during labor are not fully understood, though it is known to be partly explained by the effects of β-endorphin (BE). BE plasma levels were followed longitudinally in a cohort of pregnant women and were found to remain unchanged between early and late pregnancy, although with a nadir in the beginning of the third trimester. Furthermore, women with low levels of BE in plasma at the end of the third trimester, required second line labor analgesia to a significantly higher extent than women with normal levels. In a population-based sample of 814 pregnant women we investigated if inter-individual differences in labor pain related behavior was influenced by the pain-protective single nucleotide polymorphism (SNP) combination of guanosine triphosphate cyclohydrolase (GCH1) and the opioid receptor µ-1 gene (OPRM1) A118G SNP. We identified a possible association between the pain-protective SNP combination of GCH1 and use of second line analgesia. No association was found between the OPRM1 and use of analgesia or labor pain related behavior. The association between self-rated antenatal depressed mood and anxiety in relation to pain behaviors and self-reported pain during labor was investigated. We found that depressed mood during pregnancy is associated with early arrival to the delivery department, whereas antenatal anxiety is associated with increased self-rated pain prior to labor analgesia.  In conclusion, although an increasing number of studies strongly suggest that genetic predisposition plays an important role in pain and pain-related mechanisms, GCH1 and OPRM1 has little to offer in terms of individual counseling on labor analgesia. To enable the future use of genetic variability for pre-labor testing and counseling, a number of different genes reflecting pain mediation pathways, involving biological and psychological mechanisms, need to be analyzed in combination.

Chronic abdominal pain is a major cause of patient morbidity in inflammatory bowel diseases (IBD). A balance of pro- and anti-nociceptive factors regulating colonic dorsal root ganglion (DRG) neurons, which synapse onto second order dorsal horn neurons, are known to regulate chronic pain but the mechanisms are poorly understood. This thesis examined whether neuroanatomical remodeling of DRG central nerve terminals underlies pro-nociceptive signaling and whether subsets of immune cells source the anti-nociceptive factor, β-endorphin. To examine pro-nociceptive mechanisms, acute and chronic dextran sulfate sodium (DSS) mouse models of colitis were established and substance P (SP; marker of nociceptor terminals) immunohistochemistry used to investigate changes in immunoreactivity of DRG terminals in the thoracic dorsal horn (segments T9-T13). SP immunoreactivity was increased in the dorsal horn (4 fold; P < 0.001) and central canal (P < 0.001) following chronic colitis. In contrast, SP immunoreactivity was unchanged in acute colitis. However, five weeks later SP immunoreactivity was increased both in the dorsal horn (4 fold; P < 0.01) and central canal (P < 0.001). In the cervical spinal cord, SP immunoreactivity was not increased following colitis, suggesting that changes seen in the thoracic level were specific to signaling from colonic DRG neurons. Immunoreactivity for the SP NK1 receptor on second order neurons was also examined and a significant increase in immunoreactivity was observed on post-synaptic second order cell bodies following chronic DSS. This could provide an additional mechanism for enhanced SP neurotransmission centrally. ii The source of the anti-nociceptive mediator, β-endorphin, during chronic DSS colitis was investigated using magnetic cell sorting and flow cytometry. The number of β- endorphin expressing CD4+ (2.4 fold; P < 0.05) and CD11b+ (2.6 fold; P < 0.05) cells in mice increased following chronic colitis. These findings suggest that during colitis there is a time-dependent increase of SP immunoreactivity in thoracic DRG central terminals, which could play a role in pro- nociceptive signaling in chronic inflammation. These actions may be balanced by anti- nociceptive factors such as β-endorphin which are found in subsets of immune cells. / Thesis (Master, Physiology) -- Queen's University, 2012-08-29 16:28:41.166

Aim of paper is to find out what effects do physical exercises have on the psychical part of the person. Theoretical part speaks about psychology and emotions from the psychical view, and also from the biological view. It speaks about the effect of sport, group mentality and the way people in a group perceive the sport. It also mentions biological processes in the body and the substances that are made during the physical exertion. Methodical parts speaks about how we will put out hypothesis to the test. That is how, where, how long and under what circumstances will we do our experiement, and how will we evaluate it. Conclution is made of results, which containt tables and graphs with collected data and their explanation in text, evaluation and personal comments. Annexes contain the prototype of the used questionnaire. Results showed, that theoretical hypothesis, that physical activities are beneficial for a human, and statistical hypothesis both proved correct, and statistical one in 83,3% of the cases.