Cholecystokinin revisited: CCK and the hunger trap in anorexia nervosa.

OBJECTIVE: Despite a number of studies in the past decades, the role of Cholecystokinin (CCK) in anorexia nervosa (AN) has remained uncertain. In this study a highly specific assay for the biologically active part of CCK was used in patients with bulimic as well as with the restricting type of AN who were followed over the course of weight gain. METHODS: Ten patients with restricting and 13 with bulimic AN were investigated upon admission (T0), after a weight gain of at least 2 kg on two consecutive weighting dates (T1), and during the last week before discharge (T2) from inpatient treatment in a specialized clinic. Blood samples were drawn under fasting conditions and 20 and 60 minutes following a standard meal (250 kcal). Data were compared to those of eight controls matched for sex and age. Gastrointestinal complaints of patients were measured by a questionnaire at each of the follow-up time points. RESULTS: At admission, AN patients exhibited CCK-levels similar to controls both prior to and after a test meal. Pre and post-meal CCK levels increased significantly after an initial weight gain but decreased again with further weight improvement. CCK release was somewhat lower in bulimic than in restricting type AN but both subgroups showed a similar profile. There was no significant association of CCK release to either initial weight or BMI, or their changes, but CCK levels at admission predicted gastrointestinal symptom improvement during therapy. CONCLUSIONS: Normal CCK profiles in AN at admission indicates hormonal responses adapted to low food intake while change of eating habits and weight gain results in initially increased CCK release (counteracting the attempts to alter eating behavior) that returns towards normal levels with continuous therapy.

Cognitive functioning during methadone and buprenorphine treatment: results of a randomized clinical trial.

Cognitive impairment in drug-dependent patients receiving methadone (MMP) maintenance treatment has been reported previously. We assessed cognitive functioning after at least 14 days of stable substitution treatment with buprenorphine (BUP) or MMP and after 8 to 10 weeks. We performed a randomized, nonblinded clinical trial in 59 drug-dependent patients receiving either BUP or MMP maintenance treatment and healthy normal controls (n = 24) matched for sex, age, and educational level. Thirteen patients dropped out of the study before the second testing was performed (BUP, n = 22; MMP, n = 24). A neuropsychological test battery was used to measure selective attention, verbal memory, motor/cognitive speed, and cognitive flexibility. In addition, subjective perceived stress was assessed with a questionnaire. Patients in both treatment groups performed equally well in all of the cognitive domains tested. Both BUP and MMP patients showed significantly improved concentration and executive functions after 8 to 10 weeks of stable substitution treatment. The control group achieved better results than the BUP and MMP groups in most cognitive domains, indicating cognitive impairment in the patients. Perceived stress did not show any significant change after 8 to 10 weeks of treatment, and no major differences were detected between the 3 groups. No effects of perceived stress on cognitive function were found. Our results indicate a cognitive impairment in patients receiving maintenance treatment with BUP or MMP compared with healthy controls. Selective attention improved in both patient groups during treatment. We propose that the improvement of attention may facilitate rehabilitation of drug-dependent patients.

Influence of microgravity on plasma levels of gastroenteropancreatic peptides: a case study.

BACKGROUND: No data are available about the short- or long-term influences of microgravity in space on the release of gastroenteropancreatic peptides, although these peptides are involved in the regulation of gastrointestinal functions. METHODS: Fasting plasma samples were gained during the EUROMIR-94 mission from a European Space Agency (ESA) astronaut who experienced no signs of space motion sickness in orbit. Plasma concentrations of nine gastroenteropancreatic peptides were measured with sensitive and specific radioimmunoassays. RESULTS: Fasting plasma levels of motilin, pancreatic polypeptide (PP), vasoactive intestinal peptide (VIP), and secretin were increased and plasma level of cholecystokinin (CCK) was decreased by acute exposure of the astronaut to microgravity. Chronic (4 wk) exposure caused an enhancement of plasma CCK, motilin, neurotensin, VIP, and insulin whereas plasma concentrations of PP, secretin, gastrin, and somatostatin showed no changes. During the 25-d stay on MIR station plasma levels of CCK, motilin, and neurotensin increased. Short-time body rotations caused an elevation of plasma levels of PP but decreased plasma motilin. CONCLUSIONS: As the influence of microgravity on the peptide levels was not uniform, an effect due to other factors (e.g., change in fluid balance or body weight) is unlikely. Moreover, adaptive changes of some peptides occurred during the stay in orbit. The release of PP and motilin seems to be very sensitive to rotation forces. These results have to be confirmed in more subjects in space to be able to link changes of gastroenteropancreatic peptide release to alterations of gastrointestinal functions.