Haloperidol when applied intraperitoneally to cold-exposed febrile rabbits induces a strong hypothermic effect. This effect is due to the downward shift of the threshold central temperature for induction of cold thermogenesis and vasomotion. The shift occurs during the early phase of the fever and is less prominent during the late phase of the fever. The hypothermic effect of high doses of haloperidol can eliminate the increase of body temperature in febrile individuals.
Peptides ghrelin, obestatin and neuropeptide Y (NPY) play an important role in regulation of energy homeostasis, the imbalance of which is associated with eating disorders anorexia (AN) and bulimia nervosa (BN). The changes in ghrelin, obestatin and NPY plasma levels were investigated in AN and BN patients after administration of a high-carbohydrate breakfast (1604 kJ). Eight AN women (aged 25.4±1.9; BMI: 15.8±0.5), thirteen BN women (aged 22.0±1.05; BMI: 20.1±0.41) and eleven healthy women (aged 25.1±1.16; BMI: 20. 9±0.40) were recruited for the study. We demonstrated increased fasting ghrelin in AN, but not in BN patients, while fasting obestatin and NPY were increased in both AN and BN patients compared to the controls. Administration of high-carbohydrate breakfast induced a similar relative decrease in ghrelin and obestatin plasma levels in all groups, while NPY remained increa sed in postprandial period in both patient groups. Ghrelin/obestatin ratio was lower in AN and BN compared to the controls. In conclusions, increased plasma levels of fasting NPY and its unchanged levels after breakfast indicate that NPY is an important marker of eating disorders AN and BN. Different fasting ghrelin and obestatin levels in AN and BN could demonstrate their diverse functions in appetite and eating suppression., D. Sedláčková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The aim of this study was to ascertain whether repeated local cooling induces the same or different adaptational responses as repeated whole body cooling. Repeated cooling of the legs (immersion into 12 °C water up to the knees for 30 min, 20 times during 4 weeks = local cold adaptation – LCA) attenuated the initial increase in heart rate and blood pressure currently observed in control subjects immersed in cold water up to the knees. After LCA the initial skin temperature decrease tended to be lower, indicating reduced vasoconstriction. Heart rate and systolic blood pressure appeared to be generally lower during rest and during the time course of cooling in LCA humans, when compared to controls. All these changes seem to indicate attenuation of the sympathetic tone. In contrast, the sustained skin temperature in different areas of the body (finger, palm, forearm, thigh, chest) appeared to be generally lower in LCA subjects than in controls (except for temperatures on the forehead). Plasma levels of catecholamines (measured 20 and 40 min after the onset of cooling) were also not influenced by local cold adaptation. Locally cold adapted subjects, when exposed to whole body cold water immersion test, showed no change in the threshold temperature for induction of cold thermogenesis. This indicates that the hypothermic type of cold adaptation, typically occurring after systemic cold adaptation, does not appear after local cold adaptation of the intensity used. It is concluded that in humans the cold adaptation due to repeated local cooling of legs induces different physiological changes than systemic cold adaptation.