Psychoendocrine and metabolic reactions during standardized stressor exposure (color-word conflict test and forced mental arithmetics) were studied in ten psoriatic and ten matched healthy subjects. During resting conditions, the groups were similar with regard to psychologic and biochemical variables, except for plasma glucose, which was slightly elevated in the psoriatic group. During stressor exposure, the psoriatic group reported significantly higher strain levels. Blood pressure, pulse rate, plasma glucose, and urinary adrenaline excretion increased in both groups during exposure, with more pronounced increases of the latter two in the psoriatic group. Serum cortisol, prolactin, progesterone and urinary cortisol decreased in both groups during stressor exposure. The decrease in serum cortisol was more pronounced in the psoriatic group. Thus, no psychoendocrine differences were found between the healthy and psoriatic subjects during resting conditions. In contrast, during a standardized stressor exposure, psoriatic subjects reported higher levels of strain, which was accompanied by higher levels of urinary adrenaline and lower levels of plasma cortisol. These results fit the hypothesis that psoriatic patients perceive certain challenging situations as more stressful than do nonpsoriatic controls, and react accordingly in their differential psychoendocrine reaction pattern. Possible pathophysiologic implications of the different pituitary-adrenocortical and sympatho-adrenomedullary reactions in psoriatics submitted to stressor exposure are discussed.

The effect of various opioid or putative neurotransmitter peptides on histamine-induced itch and flare responses was studied in humans after intradermal injection. Significant enhancement of the histamine responses was induced by the stable methionine-enkephalin analogue FK 33-824, beta-endorphin and morphine. The putative neurotransmitters substance P and vasoactive intestinal polypeptide (VIP)--which moreover are potent histamine liberators--had no enhancing effect. The potentiation induced by FK 33-824 was induced neither by local pretreatment with Compound 48/80 to deplete the local stores of mast-cell-bound histamine, nor by oral pretreatment with indomethacin to inhibit prostaglandin formation in the skin. Thus, the enhancement did not seem to be due to histamine release or to prostaglandin formation and the mechanism of the effect remains to be shown. The specific morphine antagonist naloxone did not inhibit the potentiation by FK 33-824, which might indicate that ordinary opiate receptors were not involved. The results support the idea that pain and itch are qualitatively separate processes and suggest possible mechanisms of morphine-induced pruritus. The findings are of particular interest in view of recent reports on the presence of methionine-enkephalin in Merkel cells.

No abstract

In the present study a survey has been performed of the pain development and analgesic intake in 100 patients following elective oral surgery of impacted third molars in relation to preoperative assessment of personality characteristics. Our results show that no sex differences existed preoperatively concerning personality characteristics, concerning postoperative pain development or analgesic consumption. Fourteen patients reported no pain at all and 40 patients did not use any analgesics in the postoperative period. We also found a good correlation between total sum of pain scores and analgesic intake. Patients undergoing surgery in the morning reported a lower total sum of pain scores, reported pain at fewer occasions and tended to require less analgesics than patients being subjected to surgery in the afternoon. The patients who reported a total sum of pain scores in the upper percentile during the postoperative period rated their general health worse, as rated on the General Health (GH) questionnaire, and used more analgesics than did patients in the lower percentile. Also, patients not using any analgesics reported less symptoms of distress according to the GH scale as compared to patients using analgesics. In general, however, less than 10% of the variance in postoperative pain and consumption of analgesics could be explained by the preoperative factors studied.

No abstract