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The article traces the history of the "International Journal of Obesity" and the beginnings of medical journalism.

Background:Weight loss reduces energy expenditure, but the contribution of different macronutrients to this change is unclear.Hypothesis:We tested the hypothesis that macronutrient composition of the diet might affect the partitioning of energy expenditure during weight loss.Design:A substudy of 99 participants from the Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST) trial had total energy expenditure (TEE) measured by doubly labeled water, and resting energy expenditure (REE) measured by indirect calorimetry at baseline and repeated at 6 months in 89 participants. Participants were randomly assigned to one of four diets with either 15 or 25% protein and 20 or 40% fat.Results:TEE and REE were positively correlated with each other and with fat-free mass and body fat, at baseline and 6 months. The average weight loss of 8.1±0.65 kg (least-square mean±s.e.) reduced TEE by 120±56 kcal per day and REE by 136±18 kcal per day. A greater weight loss at 6 months was associated with a greater decrease in TEE and REE. Participants eating the high-fat diet (HF) lost significantly more fat-free mass (1.52±0.55 kg) than the low-fat (LF) diet group (P<0.05). Participants eating the LF diet had significantly higher measures of physical activity than the HF group.Conclusion:A greater weight loss was associated with a larger decrease in both TEE and REE. The LF diet was associated with significant changes in fat-free body mass and energy expenditure from physical activity compared with the HF diet. [ABSTRACT FROM AUTHOR]

Background:Osborne-Mendel (OM) rats are prone to obesity when fed a high-fat diet, whereas S5B/Pl (S5B) rats are resistant to diet-induced obesity when fed the same diet. OM rats have a decreased satiation response to fatty acids infused in the gastrointestinal tract, compared to S5B rats. One possible explanation is that OM rats are less sensitive to the satiating hormone, glucagon-like peptide 1 (GLP-1). GLP-1 is produced in the small intestine and is released in response to a meal. The current experiments examined the role of GLP-1 in OM and S5B rats.Methods:Experiment 1 examined preproglucagon mRNA expression in the ileum of OM and S5B rats fed a high-fat (55% kcal) or low-fat (10% kcal) diet. Experiment 2 investigated the effects of a 2 h high-fat meal after a 24 h fast in OM and S5B rats on circulating GLP-1 (active) levels. Experiment 3 examined the effects of exendin-4 (GLP-1 receptor agonist) administration on the intake of a high-fat or a low-fat diet in OM and S5B rats.Results:Preproglucagon mRNA levels were increased in the ileum of OM rats compared to S5B rats and were increased by high-fat diet in OM and S5B rats. OM and S5B rats exhibited a similar meal-initiated increase in circulating GLP-1 (active) levels. Exendin-4 dose dependently decreased food intake to a greater extent in S5B rats compared to OM rats. The intake of low-fat diet, compared to the intake of high-fat diet, was more sensitive to the effects of exendin-4 in these strains.Conclusions:These results suggest that though OM and S5B rats have similar preproglucagon mRNA expression in the ileum and circulating GLP-1 levels, OM rats are less sensitive to the satiating effects of GLP-1. Therefore, dysregulation of the GLP-1 system may be a mechanism through which OM rats overeat and gain weight. [ABSTRACT FROM AUTHOR]

Objective:A reduction in glycogen after the switch to an isoenergetic high-fat diet (HFD) might promote a compensatory increase in food intake to reestablish carbohydrate balance. We assessed the effect of an isoenergetic switch from a 49%-carbohydrate to 50%-fat diet on nutrient balance and ad libitum food intake. We hypothesized that carbohydrate balance would be inversely related to ad libitum energy intake.Methods:In 47 men and 11 women (22.6±0.4 years; 26.1±0.5 kg m–2), fuel balance was measured in a respiration chamber over 4 days. During the first day, an isoenergetic, high-carbohydrate diet was provided followed by a 3-day isoenergetic, HFD. At the end of this period and after 16 h of fasting, three options of foods (cookies, fruit salad and turkey sandwich) were offered ad libitum for 4 h. The relationships between post-chamber ad libitum intake and macronutrient oxidation and balance measured day-to-day and over the 4-day respiration chamber stay were studied.Results:After switching to a HFD, 24-h respiratory quotient decreased from 0.87±0.02 to 0.83±0.02 (P<0.0001) resulting in a 4-day cumulative carbohydrate, fat and protein balances of −183±368, 342±480 and 65±267 kcal, respectively. Cumulative energy balance (224±362 kcal per 4 days) did not influence ad libitum energy intake. However, we detected that 4-day carbohydrate balance was a positive and independent predictor of post-chamber ad libitum energy intake (R 2=0.10; P=0.01), whereas no significant influence of fat and protein balances was found.Conclusion:In response to an isoenergetic change from a high-carbohydrate to HFD, higher carbohydrate balance related to increased energy intake. [ABSTRACT FROM AUTHOR]

The aim of the study was to examine the determinants of oral glucose tolerance in 602 persons with impaired glucose tolerance (IGT) who participated in the Actos Now for Prevention of Diabetes (ACT NOW) study. In addition to the 602 IGT participants, 115 persons with normal glucose tolerance (NGT) and 50 with impaired fasting glucose (IFG) were identified during screening and included in this analysis. Insulin secretion and insulin sensitivity indices were derived from plasma glucose and insulin during an OGTT. The acute insulin response (AIR) (0–10 min) and insulin sensitivity (SI) were measured with the frequently sampled intravenous glucose tolerance test (FSIVGTT) in a subset of participants. At baseline, fasting plasma glucose, 2 h postprandial glucose (OGTT) and HbA1c were 5.8 ± 0.02 mmol/l, 10.5 ± 0.05 mmol/l and 5.5 ± 0.04%, respectively, in participants with IGT. Participants with IGT were characterised by defects in early (∆ I0–30/∆ G0–30 × Matsuda index, where ∆ I is change in insulin in the first 30 min and ∆ G is change in glucose in the first 30 min) and total (∆I0–120/∆G0–120 × Matsuda index) insulin secretion and in insulin sensitivity (Matsuda index and SI). Participants with IGT in whom 2 h plasma glucose was 7.8–8.3 mmol/l had a 63% decrease in the insulin secretion/insulin resistance (disposition) index vs participants with NGT and this defect worsened progressively as 2 h plasma glucose rose to 8.9–9.94 mmol/l (by 73%) and 10.0–11.05 mmol/l (by 80%). The Matsuda insulin sensitivity index was reduced by 40% in IGT compared with NGT ( p < 0.005). In multivariate analysis, beta cell function was the primary determinant of glucose AUC during OGTT, explaining 62% of the variance. Our results strongly suggest that progressive beta cell failure is the main determinant of progression of NGT to IGT. [ABSTRACT FROM AUTHOR]

Reinforced structures for aircraft fuselages are conventionally composed by base (skin) aluminium plates and reinforcement elements (stringers), joined by riveting operations. During the last decade more effective approaches for reinforced fuselage and wings, such as the Integrally Stiffened Panels (ISP), have appeared. These homogeneous reinforced structures are obtained in an integral form by extrusion, allowing for lower manufacturing costs. During service conditions, these structures can be subjected to extreme compressive loading conditions and, due to their slenderness and low weight, ISP design must account for a reliable determination of buckling loads. However, complexities of the cross-sectional geometrical shapes, together with the occurrence of elastoplastic non-linear effects prior or after buckling, completely impair the use of analytical tools, being the analysis by the Finite Element Method (FEM) imperative in a reliable design process. In the present work, the structural performance of ISP structures is assessed, accounting for buckling in the elastoplastic range, by means of numerical simulation with the Finite Element Method. Also, the buckling load-carrying capacity of multiple sets of reinforced structures, composed by a finite number of ISP and joined by friction stir welding (FSW) operations, is also studied. In doing so, it is possible to numerically infer about the influence of the presence of FSW zones in the overall stiffness and mechanical behaviour of ISP structures with complex cross-section geometries. [ABSTRACT FROM AUTHOR]

Obesity is a growing problem. In the broadest strokes, it is due to a small positive energy balance that persists over a sufficiently long time. Some forms of obesity develop independent of the type of diet that is eaten, whereas others are dependent on the diet. Among the former are individuals with leptin deficiency or genetic defects in the melanocortin 4 receptor. Most human obesity, however, occurs in the presence of highly palatable foods—fat and calorically sweetened beverages. The increase in obesity in the last 35 years has paralleled the increasing use of high-fructose corn syrup (HFCS), which first appeared just before 1970. Current soft drinks and many other foods are sweetened with this product because it is inexpensive and has useful manufacturing properties. The fructose in HFCS and sugar makes beverages very sweet, and this sweetness may underlie the relation of obesity to soft drink consumption. Fructose consumption has also been related to the metabolic syndrome and to abnormal lipid patterns. This evidence suggests that we should worry about our current level of fructose consumption, which has been increasing steadily for over 200 years and now represents over 10% of the energy intake of some people.International Journal of Obesity (2008) 32, S127–S131; doi:10.1038/ijo.2008.248 [ABSTRACT FROM AUTHOR]

Objective:Following unblinding of the Diabetes Prevention Program (DPP) results, a 16-session lifestyle intervention program was offered to all study participants, including those who had initially been randomized to lifestyle treatment. This study compares the effects of the lifestyle program between participants who had previous exposure and those who had not.Design:A 16-session behavioral intervention was conducted in groups at each of the 27 DPP sites during a transitional (bridge) period from the DPP trial to the DPP Outcomes Study (DPPOS). Session participation for this 6-month behavioral weight loss program was confirmed by originally randomized treatment groups.Subjects and measurements:Independently assessed weight measurements were available within a 7-month period before and after the program for 2808 ethnically diverse participants.Results:Participants from the lifestyle group in the DPP were the least likely to attend a repeat offering of a 16-session behavioral weight loss program conducted in groups. Weight loss during the transitional lifestyle program was strongly related to the duration of attendance in the three groups that were participating in the program for the first time (metformin, placebo and troglitazone), but not related to amount of earlier weight loss.Conclusion:Individuals who were naive to the behavioral program lost a greater amount of weight and this was strongly related to their degree of participation. A second exposure to a behavioral weight loss program resulted in unsatisfactory low attendance rates and weight loss.International Journal of Obesity (2008) 32, 1537–1544; doi:10.1038/ijo.2008.134; published online 19 August 2008 [ABSTRACT FROM AUTHOR]

Objective:To identify differences in amount and distribution of fat and lean soft tissue in a cross-sectional study of subjects with and without type 2 diabetes and to determine whether any differences are affected by race/ethnicity or sex.Design and methods:Overweight and obese (body mass index, BMI25 kg m−2) Black, White and Hispanic men (490) and women (825) with type 2 diabetes ((mean±s.d.) age 58.5±6.6; BMI 35.3±5.3) who had a baseline dual energy X-ray absorptiometry whole-body scan at the time of enrollment in the Look AHEAD clinical trial, and 242 healthy controls, 91 males and 151 females (age 55.3±8.6 years, BMI 30.7±4.2 kg m−2) who were participating in unrelated research and were scanned on the same densitometers.Results:Adjusted for gender, age, race, clinical site and body size, total fat mass was smaller in persons with type 2 diabetes than in controls (−1.4±0.3 (s.e.); 34.5 vs 35.8 kg, P<0.001) while trunk fat was larger (1.3±0.2 (s.e.); 19.9 vs 18.6 kg, P<0.001) and leg fat was smaller (−1.5±0.2 (s.e.); 10.7 vs 12.3 kg, P<0.001). The arms of subjects with type 2 diabetes did not have significantly less fat compared to controls. Adjusted trunk lean mass was larger in type 2 diabetes by 0.6 kg (28.4 vs 27.8 kg, P<0.001) while leg lean was smaller by 0.5 kg (18.1 vs 18.6 kg, P<0.001).Conclusions:Type 2 diabetes is associated with less total fat, leg fat and leg lean mass and more truncal fat and lean mass than controls. The physiological processes producing these deviations in tissue distribution and their metabolic significance warrant further investigation.International Journal of Obesity (2008) 32, 780–787; doi:10.1038/sj.ijo.0803802; published online 29 January 2008 [ABSTRACT FROM AUTHOR]

High-cycle fatigue tests were carried out on a newly developed high-strength AA 2026 Al alloy, which was in the form of extrusion bars with square and rectangular cross sections, using a sell-aligning four-point-bend rig at room temperature, 15 Hz, and R = 0.1, in lab air. The fatigue strength of the square and rectangular bars was measured to be 85 and 90 pct of their yield strength, respectively, more than twice that of the predecessor to the 2026 alloy (the AA 2024 Al alloy). Fatigue cracks were found to be always initiated at large Ω′ (Al7Cu2(Fe,Mn)) particles and to propagate predominantly in a crystallographic mode in the AA 2026 alloy. The fatigue fractographies of the square and rectangular extrusion bars were found to be markedly different, due to their different grain structures (fibril and layered, respectively). Fracture steps on the crack face were found in both of these extrusion bars. Since the 2026 alloy was purer in terms of Fe and Si content, it contained much less coarse particles than in a 2024 alloy. This partially accounted for the superior fatigue strength of the 2026 alloy. [ABSTRACT FROM AUTHOR]

OBJECTIVE:To compare the estimation of body fat between bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DEXA) in overweight, African-American female adolescents.SUBJECTS:In total, 54 African-American adolescent female subjects were recruited for Study 1. Each adolescent's body mass index was greater than the 85th percentile and their average body fat was 45%according to DEXA. A total of 26 African-American adolescent female subjects were available for Study 2, and had an average body fat of 26%according to DEXA.MEASUREMENTS:Percent body fat was measured by DEXA and BIA. Seven different BIA equations were tested. Both sets of data were analyzed using Bland-Altman regression analyses, utilizing percent body fat measured by DEXA as the criterion.RESULTS:The Kushner equation provided estimates that were unaffected by body fat in both studies. Estimates were unbiased when applied to the exclusively overweight sample and biased when utilized with the separate sample of normal weight and obese girls. The remaining equations were biased, provided inconsistent estimates across body weight, or were biased and provided inconsistent estimates. Ethnicity-specific and ethnicity-combined equations performed similarly in the obese sample, but became more disparate when applied to a sample encompassing a wider body weight range. The limits of agreement between all BIA equations and the DEXA estimates ranged from 6 to 9%.CONCLUSION:The study suggests that the Kushner BIA equation is appropriate for use with African-American female adolescents across the weight spectrum, while the majority of BIA equations underestimated percent body fat as body fat increased.International Journal of Obesity (2005) 29, 594-602. doi:10.1038/sj.ijo.0802968 [ABSTRACT FROM AUTHOR]

BACKGROUND:: There is a continuing need to examine the relationship between diet quality and health in the population. The Healthy Eating Index (HEI) has been developed as a composite measure of diet quality by the US Department of Agriculture. OBJECTIVES:: The first objective was to use the HEI to assess the diet quality of a representative sample of the US population and population groups. The second objective was to examine the association between HEI and obesity. DESIGN:: Cross-sectional analysis of data from 10?930 adults who participated in the Third National Health and Nutrition Examination Survey. Sociodemographic, physical activity, dietary, and health data were used in the analysis. Diet quality was assessed with the HEI score, ranging from 0 to 100, based on 10 dietary criteria. A low HEI score indicates poor diet. RESULTS:: A majority of survey participants had a low HEI score. The percentage of individuals classified as having a poor diet varied by age, gender, race/ethnicity, income, and education. A low HEI score was associated with overweight and obesity. There was a graded increase in the odds ratio of obesity across the HEI category after adjusting for age, gender, race/ethnicity, physical activity, smoking, alcohol use, income, and education. CONCLUSIONS:: An index of diet quality, such as HEI, may provide a comprehensive assessment of diet in the population. Since the HEI is based on the US Dietary Guidelines, the use of these guidelines as a way to improve health should be emphasized. However, the overall effectiveness of these guidelines in disease prevention needs to be studied further. SPONSORSHIP:: None.European Journal of Clinical Nutrition (2004) 58, 1580-1586. doi:10.1038/sj.ejcn.1601989 Published online 19 May 2004 [ABSTRACT FROM AUTHOR]

A robust algorithm for pull-calorimeters that provides a rapid response to changes in respiratory gas exchange has been implemented. Metabolic plateaus (over 20 min), such as that generated by steady treadmill exercise, can be measured accurately (< 2.0% error for an energy expenditure level of 16.7 kJ min(-1)). The time resolution for changes between plateaus can be accurately found with 1 min discrimination. Implementation required only software changes but no structural or instrumentation changes to the chamber. The algorithm was based on the one developed for the push-calorimeter at the Sahlgrenska Hospital in Sweden. The method utilises published equations for the rate of O2 consumption and CO2 production in the chamber, along with techniques for suppressing noise and identifying trends. Using the exact solution of the equations for steady state, the O2 concentrations from the preceding 30 min period are fitted to two connected exponential segments, of variable length, using the least-squares method. The smoothed O2 concentration and associated time derivative are then determined for the time point 15 min earlier and substituted into the respiration equations. The CO2 concentrations are subjected to the same analysis. The process is repeated every minute, and the newly computed rates of O2 consumption and CO2 production, as well as metabolic rate, are then presented. Gas injection tests proved that the chamber can respond instantaneously to a change from one steady state of respiration to another and correctly averages repeated changes in respiration with periods less than 15min (< 1.4% error for simulated, alternating O2 consumption levels of 0.81 min (-1) and 0.01 min). The successful integration of the algorithm into the Pennington chambers allows for traditional 24 h energy expenditure measurements and various metabolic experiments requiring rapid responses. [ABSTRACT FROM AUTHOR]

In ingot metallurgy (IM) alloys, the number of delay cycles following a single tensile overload typically increases from a minimum at an intermediate baseline stress intensity range, ΔK, with decreasing ΔK approaching threshold and increasing ΔK approaching unstable fracture to produce a characteristic 'U'-shaped curve. Two models have been proposed to explain this behavior. One model is based on the interaction between roughness and plasticity-induced closure, while the other model only utilizes plasticity-induced closure. This article examines these models using experimental results from constant amplitude and single overload fatigue tests performed on two powder metallurgy (PM) aluminum alloys, AL-905XL and A A 8009. The results indicate that the 'U'-shaped curve is primarily due to plasticity-induced closure, and that the plasticity-induced retardation effect is through-thickness in nature, occurring in both the surface and interior regions. However, the retardation effect is greater at the surface, because the increase in plastic strain at the crack tip and overload plastic zone size are larger in the plane-stress surface regions than in the plane-strain interior regions. These results are not entirely consistent with either of the proposed models. [ABSTRACT FROM AUTHOR]

Regenerated retinal ganglion cell (RGC) axons can re-form functional synapses with target neurons in the superior colliculus (SC). Because preterminal axon branching determines the size, shape and density of innervation fields, we investigated the branching patterns and bouton formation of individual RGC axons that had regrown along peripheral nerve (PN) grafts to the SC. Within the superficial layers of the SC, the regenerated axons formed terminal arbors with average numbers of terminal boutons that were similar to the controls. However, axonal branches were shorter than normal so that the mean area of the regenerated arbors was nearly one-tenth that of control arbors and the resulting fields of innervation contained greater than normal numbers of synapses concentrated in small areas of the target. Our results have delineated a critical defect in the reconstitution of retino-collicular circuitry in adult mammals: the failure of terminal RGC branches to expand appropriately. Because recent studies have documented that brain-derived neurotrophic factor (BDNF) can specifically lengthen RGC axonal branches not only during development in the SC but also within the adult retina after axotomy, the present quantitative studies should facilitate experimental attempts to correct this deficit of the regenerative response. © 1998 Chapman and Hall [ABSTRACT FROM AUTHOR]

Several lines of evidence support the hypothesis that derangements in the function of the autonomic nervous system play an important role in the development of hypothalamic obesity. Vagotomy below the diaphragm reverses the syndrome. In diabetic rats cured of their diabetes with transplants of fetal pancreatic tissue beneath the renal capsule, ventromedial hypothalamic (VMH) lesions do not produce the characteristic rise in food intake nor do they significantly increase serum insulin. These observations indicate that the hyperinsulinaemia following VMH lesions is the result of neural connections rather than from a circulating humoral factor released following VMH injury. The smaller salivary glands, reduced level of glucagon and impaired mobilization of fatty acids during stress in VMH lesioned rats point to reduced activity of the sympathetic nervous system. The impaired mobilization of fat from retroperitoneal depots in VMH lesioned rats during fasting is similar to the effect of sympathetic denervation of the retroperitoneal fat pad. Similarly, unilateral sympathectomy caused an increased weight gain in rats almost as much as unilateral VMH lesions but significantly less than in bilaterally lesioned rats. These studies with fasting and feeding implicate the VMH in the control of the sympathetic nervous system. When atropine and epinephrine were given to VMH lesioned rats, there was a significant depression in basal and glucose-stimulated levels of insulin. Finally when VMH lesions were placed after lateral hypothalamic lesions, the effect of the VMH lesions did not seem to be reduced, suggesting that the two effects are independent. A model dealing with the effects of VMH lesions is presented in an attempt to integrate these findings. [ABSTRACT FROM AUTHOR]

The expression of specific calcium binding proteins is being used increasingly as a potential neuroanatomical marker for neurons with similar functions. In this study, the distribution of calbindin D28k in the superior colliculus (SC) of adult hamsters was examined by light and electron microscopy. Calbindin immunoreactivity was prominent in specific regions and laminae of the SC throughout its rostrocaudal extent, and was found to label horizontal, vertical and stellate cell types. In addition, calbindin label highlighted 'bridges' of neuronal processes in the intermediate layers. The most frequent calbindin-immunoreactive profiles seen in the electron microscope were dendrites, some of which were post-synaptic to apparent retinal ganglion cell axon terminals. Labelled axons and axon terminals were less frequently encountered. There was considerable overlap between the size distribution of calbindin D28k-immunoreactive neurons and that of GABA-immunoreactive or Nissl stained neurons in the SC. However, using a double fluorescent labelling technique, and examination of the tissue with confocal laser microscopy, no neurons were observed in the hamster SC that showed immunoreactivity for both calbindin and GABA. In this regard, the SC is similar to the mammalian lateral geniculate nucleus and the pretectum, but differs from the neocortex, where calbindin and GABA are colocalized. The demonstration in the SC, as well as other parts of the nervous system, of sub-populations of neurons that contain distinct calcium-binding proteins suggests that these neurons have different functional properties. Correlative studies may clarify the relevance of these cytoplasmic components as cell markers, as well as their different patterns of association with neurotransmitters and peptides. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Anaesthetists' Society Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rats were exposed for approximately 1 month to a single stimulus mounted on the home cage wall. During discrimination training, half of the Ss had the exposed figure as the positive stimulus and half the exposed figure as the negative stimulus. Control Ss had no pattern mounted on the wall. The results indicate that when the exposed figure was the positive stimulus, the Ss made significantly more errors than the control Ss. but when the exposed figure was the negative stimulus, the Ss made significantly fewer errors. These results are consistent with the exploratory literature, which suggests that exposure to a stimulus will reduce the invitational properties of that stimulus relative to a more novel stimulus and thereby will affect the probability of selecting one stimulus over another, at least for a period of time, in a discrimination task. [ABSTRACT FROM AUTHOR]

Copyright of Experientia is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A correction to the article "First versus repeat treatment with a lifestyle intervention program: attendance and weight loss outcomes," that was published in the 2008 issue is presented.

A foreword to "International Journal of Obesity" is presented.

The neuropeptides, monoamines and many drugs involved with modulating food intake and fat stores have reciprocal effects on sympathetic activity and thermogenesis. Both serotonin, acting through 5HT[sub1B/2C] receptors, and norepinephrine acting through β[sub2] and/or β[sub3] receptors reduce food intake and augment sympathetic activity. Neuropeptide Y, β-endorphin, orexin, galanin and melanin concentrating hormone all increase food intake and, where tested, reduce sympathetic activity. In contrast, a larger number of peptides including cholecystokinin, corticotrophin-releasing hormone/urocortin, enterostatin, leptin, CART and α-MSH reduce food intake and increase sympathetic activity. Nicotine, prostaglandin, dexfenfluramine and sibutramine also have this reciprocal effect on feeding and sympathetic nervous system (SNS) activity. Chronic administration of neuropeptide Y (NPY) can produce chronically increased food intake and obesity. This syndrome is similar to the ventromedial hypothalamus (VMH) syndrome and suggests that NPY must be acting as an inhibitory signal to stimulate a feeding system and inhibit sympathetic activity. The melanocortin receptor system may be particularly important in modulating food intake, because a transgenic mouse which does not express melanocortin-4 receptors is massively overweight. Adrenal glucocorticoids are important in obesity since adrenalectomy will reverse or prevent the development of all forms of obesity. The clinical importance of the sympathetic nervous system and food intake is emphasized by the inverse relation of sympathetic activity and body fat. The inhibition of food intake, lower body fat stores and higher energy expenditure in smokers also support this hypothesis. The reciprocal relationship between food intake and sympathetic activity is robust, suggesting that β receptors in the periphery and brain may be involved in the control of feeding and a reduction in food intake in humans... [ABSTRACT FROM AUTHOR]