Calcitonin gene-related peptide in human obesity

Plasma level of calcitonin gene-related peptide in patients with polycystic ovary syndrome and its relationship to hormonal and metabolic parameters

The aim of the study was to evaluate the plasma level of calcitonin gene-related peptide (CGRP) in patients with polycystic ovary syndrome (PCOS) and its relationship to hormonal and metabolic parameters. We also observed the effect of CGRP on testosterone (T) and estradiol (E(2)) release in cultured human granulosa cells. PCOS subjects (n=215) and matched healthy control women (n=103) at age of 22-38 years were enrolled in this study. We analyzed plasma CGRP concentrations, relationship of plasma CGRP with insulin resistance (IR), body mass index (BMI), luteinizing hormone/follicle-stimulating hormone (LH/FSH) ratio and T. The T and E(2) release levels of cultured human granulosa cells treated by CGRP were also measured. The results showed that plasma CGRP concentrations were significantly higher in women with PCOS than those of control subjects. In women with PCOS, there was a strong positive correlation between the plasma CGRP level with HOMA-IR, AUC-insulin, AUC-glucose, the ratio of LH/FSH and plasma T concentration. Human granulosa cells expressed CGRP receptor. Exogenous CGRP caused an elevation of T and E(2) released from the human granulosa cells. These findings suggest that CGRP may participate in the pathophysiological process of PCOS.

Migraine and obesity: epidemiology, possible mechanisms and the potential role of weight loss treatment

Migraine and obesity are two public health problems of enormous scope that are responsible for significant quality of life impairment and financial cost. Recent research suggests that these disorders may be directly related with obesity exacerbating migraine in the form of greater headache frequency and severity, or possibly increasing the risk for having migraine. The relationship between migraine and obesity may be explained through a variety of physiological, psychological and behavioural mechanisms, many of which are affected by weight loss. Given that weight loss might be a viable approach for alleviating migraine in obese individuals, randomized controlled trials are needed to test the effect of weight loss interventions in obese migraineurs. Large-scale weight loss trials have shown that behavioural interventions, in particular, can produce sustained weight losses and related cardiovascular improvements in patients who are diverse in body weight, age and ethnicity. Consequently, these interventions may provide a useful treatment model for showing whether weight loss reduces headache frequency and severity in obese migraineurs, and offering further insight into pathways through which weight loss might exert an effect.

Glucose-dependent insulinotropic polypeptide (GIP) induces calcitonin gene-related peptide (CGRP)-I and procalcitonin (Pro-CT) production in human adipocytes

CONTEXT

Increased plasma levels of glucose-dependent insulinotropic polypeptide (GIP), calcitonin CT gene-related peptide (CGRP)-I, and procalcitonin (Pro-CT) are associated with obesity. Adipocytes express functional GIP receptors and the CT peptides Pro-CT and CGRP-I. However, a link between GIP and CT peptides has not been studied yet.

OBJECTIVE

The objective of the study was the assessment of the GIP effect on the expression and secretion of CGRP-I and Pro-CT in human adipocytes, CGRP-I and CT gene expression in adipose tissue (AT) from obese vs. lean subjects, and plasma levels of CGRP-I and Pro-CT after a high-fat meal in obese patients.

DESIGN AND PARTICIPANTS

Human preadipocyte-derived adipocytes, differentiated in vitro, were treated with GIP. mRNA expression and protein secretion of CGRP-I and Pro-CT were measured. Human CGRP-I and CT mRNA expression in AT and CGRP-I and Pro-CT plasma concentrations were assessed.

RESULTS

Treatment with 1 nm GIP induced CGRP-I mRNA expression 6.9 ± 1.0-fold (P < 0.001 vs. control) after 2 h and CT gene expression 14.0 ± 1.7-fold (P < 0.001 vs. control) after 6 h. GIP stimulated CGRP-I secretion 1.7 ± 0.2-fold (P < 0.05 vs. control) after 1 h. In AT samples of obese subjects, CGRP-I mRNA expression was higher in sc AT (P < 0.05 vs. lean subjects), whereas CT expression was higher in visceral AT (P < 0.05 vs. lean subjects). CGRP-I plasma levels increased after a high-fat meal in obese patients.

CONCLUSION

GIP induces CGRP-I and CT expression in human adipocytes. Therefore, elevated Pro-CT and CGRP-I levels in obesity might result from GIP-induced Pro-CT and CGRP-I release in AT and might be triggered by a high-fat diet. How these findings relate to the metabolic complications of obesity warrants further investigations.

Body mass index and adult weight gain among reproductive age women with migraine

OBJECTIVE

To evaluate the cross-sectional relationship between migraine and pregravid obesity; and to assess the risk of adult weight gain among women with history of a pediatric diagnosis of migraine.

BACKGROUND

Obesity, comorbid with pain disorders including migraine, shares common pathophysiological characteristics including systemic inflammation, and derangements in adipose-tissue derived cytokines. Despite biochemical and epidemiological commonalities, obesity-migraine associations have been inconsistently observed.

METHODS

A cohort of 3733 women was interviewed during early pregnancy. We ascertained participants' self-reported history of physician-diagnosed migraine and collected self-reported information about pregravid weight, adult height, and net weight change from age 18 to the 3-months period before pregnancy. Using pregravid body mass index, we categorized participants as follows: lean (< 18.5 kg/m²), normal (18.5-24.9 kg/m²), overweight (25-29.9 kg/m²), obese (30-34.9 kg/m²), severely obese (35-39.9 kg/m²), and morbidly obese (≥ 40 kg/m²). Logistic regression procedures were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

After adjusting for confounders, relative to normal weight women, obese women had a 1.48-fold increased odds of migraine (OR = 1.48; 95% CI 1.12-1.96). Severely obese (OR = 2.07; 95% CI 1.27-3.39) and morbidly obese (OR = 2.75; 95% CI 1.60-4.70) had the highest odds of migraines. Women with a history of diagnosed pediatric migraine had a 1.67-fold higher odds of gaining ≥ 10.0 kg above their weight at age 18, as compared with non-migraineurs (OR = 1.67; 95% CI 1.13-2.47).

CONCLUSION

These data support earlier observations of migraine-obesity association among women, and extend the literature to include evidence of adult weight gain among women with a history of pediatric migraine.

Calcitonin gene-related peptide: A molecular link between obesity and migraine?

Epidemiological studies have begun to suggest obesity is a risk factor for chronic migraine, although no causal relationship has been established and risk factors for progression from episodic to chronic migraine remain unknown. The neuropeptide calcitonin gene-related peptide (CGRP) plays a important role in the pathophysiology of migraine. Here, the potential role of CGRP as a molecular link between obesity and migraine is reviewed. A mechanistic association is supported by several lines of evidence: 1) common markers are elevated in obesity and migraine, 2) adipose tissue secretes proinflammatory cytokines and adipocytokines that have been implicated in migraine pathophysiology and 3) elevated levels of CGRP have been found in plasma of obese individuals. We propose that CGRP released from trigeminal neurons may represent a biological link between obesity and migraine. Enhanced trigeminal CGRP production in obese susceptible individuals may lower the threshold necessary to trigger migraine attacks, leading to more frequent episodes and eventually to chronic migraine.

Plasma calcitonin gene-related peptide concentration is comparable to control group among migraineurs and tension type headache subjects during inter-ictal period

Calcitonin gene-related peptide (CGRP) is known to increase during acute attack of migraine and tension type headache (TTH). However, its concentration during inter-ictal period is not known. This may help us to understand the pathophysiology of these headaches. The objectives of this study are to find out the concentration of CGRP in plasma during inter-ictal period among migraineurs and TTH and to compare it with control group through cross-sectional study from headache clinic of a tertiary centre. Study sample comprised of three groups: migraineurs, TTH subjects as well as a healthy control group. Fifty subjects in each group were included after screening for the respective inclusion criteria and exclusion criteria. None of the subjects was blood relatives of other subject. Their venous blood was drawn and plasma was separated to be kept at −70°C. CGRP was analysed with commercially available ELISA kit. Data were analysed with the help of SPSS V 11.0 for Windows. Chi-square, independent sample t test and one-way ANOVA with post hoc Tukey and univariate regression were performed. Plasma CGRP concentration was not different among three diagnostic groups (F = 0.78; P = 0.49). Similarly, plasma CGRP concentration was not different among episodic TTH and chronic TTH groups (t = 0.32; P = 0.97) and comparison of episodic and chronic migraine groups also revealed similar results in this study (1.14 vs. 0.94 ng/ml; P = 0.23). The presence of aura did not affect the inter-ictal CGRP levels among migraineurs (F = 0.16; P = 0.85). In conclusion, this study suggests that migraine and TTH could be episodic disorders and subjects have comparable CGRP levels during inter-ictal period.

The vascular risk associations with migraine: relation to migraine susceptibility and progression

Migraine is a common disorder in which changes in cortical excitability, neuroinflammation and dysfunction of the vascular wall contribute to its pathophysiology. Repeated attacks of migraine over prolonged periods result in inflammatory arteriopathy of the cranial vessels. Several studies indicate that migraine is associated with special pattern of inflammatory markers and some adverse vascular risk factors including: increased levels of CRP, ILs, TNF-alpha and adhesion molecules which are markers of systemic inflammation, oxidative stress and thrombosis, increased body weight, high blood pressure, hypercholesterolemia, impaired insulin sensitivity, high homocysteine levels, stroke and coronary heart disease. Such comorbidities are not explained by bias but indicate possible shared underlying pathogenic mechanisms. Recent studies have shown involvement of cranial as well as peripheral vascular dysfunction with migraine indicating that migraine may be a local manifestation of a systemic disease rather than a primary brain phenomenon. The associated inflammatory process of migraine together with the associated adverse medical comorbidities exposes patients to endothelial vascular wall injury which further increases migraine susceptibility and progression as well as increases the risk for atherogenesis. The knowledge that migraine is a risk for vascular diseases raises important clinical implications, recommendations and future perspectives in migraine treatment and prevention.

Body mass index and headaches: findings from a national sample of US adults

The objective was to study the cross-sectional association between body mass index (BMI) and the prevalence of severe headaches or migraines in a national sample of US adults. We used data from 7601 men and women aged > or = 20 years who participated in the National Health and Nutrition Examination Survey 1999-2002. The age-adjusted prevalence of severe headaches or migraines during the previous 3 months was 34.0, 18.9, 20.7 and 25.9% among participants with a BMI < 18.5, 18.5 to < 25, 25 to < 30 and > or = 30 kg/m(2), respectively. After adjusting for a variety of covariates in a logistic regression model, those with a BMI < 18.5 kg/m(2)[odds ratio (OR) 2.01; 95% confidence interval (CI) 1.34, 3.02] or > or = 30 kg/m(2 )(OR 1.37; 95% CI 1.09, 1.72) had a significantly elevated OR for having a headache compared with participants with a BMI of 18.5-< 25 kg/m(2). BMI is associated with the prevalence of severe headaches or migraines in a non-linear manner.

TRPV1-null mice are protected from diet-induced obesity

We explored a role for the capsaicin receptor, transient receptor potential channel vanilloid type 1 (TRPV1), in the regulation of feeding and body mass. On a 4.5% fat diet, wild-type and TRPV1-null mice gained equivalent body mass. On an 11% fat diet, however, TRPV1-null mice gained significantly less mass and adiposity; at 44 weeks the mean body weights of wild-type and TRPV1-null mice were approximately 51 and 34g, respectively. Both groups of mice consumed equivalent energy and absorbed similar amounts of lipids. TRPV1-null mice, however, exhibited a significantly greater thermogenic capacity. Interestingly, we found that 3T3-L1 preadipocytes expressed functional calcitonin gene-related peptide receptors. Thus, these data support a potential neurogenic mechanism by which TRPV1-sensitive sensory nerves may regulate energy and fat metabolism.

Prevalence and characteristics of allodynia in headache sufferers: a population study

OBJECTIVE

The authors estimated the prevalence and severity of cutaneous allodynia (CA) in individuals with primary headaches from the general population.

METHODS

We mailed questionnaires to a random sample of 24,000 headache sufferers previously identified from the population. The questionnaire included the validated Allodynia Symptom Checklist (ASC) as well as measures of headache features, disability, and comorbidities. We modeled allodynia as an outcome using headache diagnosis, frequency and severity of headaches, and disability as predictor variables in logistic regression. Covariates included demographic variables, comorbidities, use of preventive medication, and use of opioids.

RESULTS

Complete surveys were returned by 16,573 individuals. The prevalence of CA of any severity (ASC score >or=3) varied with headache type. Prevalence was significantly higher in transformed migraine (TM, 68.3%) than in episodic migraine (63.2%, p < 0.01) and significantly elevated in both of these groups compared with probable migraine (42.6%), other chronic daily headaches (36.8%), and severe episodic tension-type headache (36.7%). The prevalence of severe CA (ASC score >or=9) was also highest in TM (28.5%) followed by migraine (20.4%), probable migraine (12.3%), other chronic daily headaches (6.2%), and severe episodic tension-type headache (5.1%). In the migraine and TM groups, prevalence of CA was higher in women and increased with disability score. Among migraineurs, CA increased with headache frequency and body mass index. In all groups, ASC scores were higher in individuals with major depression.

CONCLUSIONS

Cutaneous allodynia (CA) is more common and more severe in transformed migraine and migraine than in other primary headaches. Among migraineurs, CA is associated with female sex, headache frequency, increased body mass index, disability, and depression.

Headaches in overweight children and adolescents referred to a tertiary-care center in Israel

OBJECTIVE

To assess the association between obesity and primary headaches in children and adolescents.

METHODS AND PROCEDURES

In a prospective study, the short-questionnaire version based on existing International Headache Society diagnostic criteria was administered. Two hundred and seventy-three children and adolescents (61% females) aged 9-17 years were assessed. One hundred and sixteen (42.5%) subjects were of normal weight, 45 (16.5%) were at risk for overweight (BMI >85th and <95th percentile for age and gender) and 112 (41%) were overweight (BMI >/=95th percentile). The outcome measures were prevalence of headaches, type of headaches, association between headaches and elevated blood pressure in overweight subjects.

RESULTS

Headache was reported in 39 (14.3%) subjects, with a similar rate in females (14.5%) and males (14%). Among 39 subjects with headaches, 20 (17.9%) were overweight, 7 (15.6%) were at risk for overweight and 12 (10.3%) were normal-weight children. Among females, 7.7% of normal-weight group suffered from headaches, compared with 14.8% of the at risk for overweight group and 20.3% of the overweight group (P for trend 0.04). Among males, the occurrence of headaches was similar in all three weight groups (P = 0.96). The occurrence of headaches increased from 10.6% among children aged 9-11 years to 21.8% in the 15-18 years age group (P < 0.05). In multivariate analysis, a significant independent risk for headaches was present in overweight females (odds ratio (OR) = 3.93, 95% confidence interval (CI) 1.28-12.1) and in adolescents aged 15-18 years (OR = 2.62, 95% CI 1.07-6.45). Elevated blood pressure was not independently associated with headaches. Of the 15 children with migraine, 12 were either at risk for overweight or overweight.

DISCUSSION

Overweight females had an almost fourfold excess risk of headaches when compared with normal-weight girls.

Modifiable Risk Factors for Migraine Progression

Migraine is a chronic-recurrent disorder that progresses in some individuals. Transformed migraine is the result of this progression. Since migraine does not progress in most patients, identifying the risk factors for progression has emerged as a very important public health priority. If risk factors can be identified, that might provide a foundation for more aggressive preventive intervention. Risk factors for progression may be divided into non-remediable (gender, age, race) and remediable categories. In this paper, we focus on several already identified remediable risk factors, including frequency of migraine attacks, obesity, acute medication overuse, caffeine overuse, stressful life events, depression, and sleep disorders. We present the evidence for each risk factor and discuss possible interventions to address them.

Effects of glucagon, insulin, amylin and CGRP on feeding

The roles of the pancreatic peptides glucagon, insulin, and amylin in the inhibitory control of feeding are reviewed. Calcitonin gene-related peptide (CGRP) is also included because it is structurally and functionally related to amylin and because known amylin and CRRP receptors are activated by both peptides. Glucagon-like peptide 1, in contrast, is structurally distinct from pancreatic glucagon and does not cross-react with glucagon receptors, so it is not considered. Several detailed reviews of the feeding effects of these peptides have appeared recently; where appropriate, these are cited rather than the primary literature.

Lesion of the area postrema/nucleus of the solitary tract (AP/NTS) attenuates the anorectic effects of amylin and calcitonin gene-related peptide (CGRP) in rats

The area postrema/nucleus of the solitary tract (AP/NTS) region plays an important role in the control of food intake since it receives peripheral satiety signals via splanchnic and vagal afferents. Due to the lack of the blood brain barrier in this region, blood borne signals can directly be monitored in the AP/NTS. Furthermore, receptors for anorectic peptides such as amylin or calcitonin gene-related peptide (CGRP) have been found in the AP/NTS. It was therefore the aim of the present study to investigate the role of the AP/NTS region in mediating the anorectic effects of these peptides. Thermal ablation of the AP/NTS resulted in a significant reduction of the anorectic effects of IP injected amylin (5 microg/kg) and CGRP (5 microg/kg) in food deprived rats. The anorectic actions of CCK and BBS were also reduced by the AP/NTS lesion which agrees with previous studies. We conclude that the AP/NTS region is an important brain site for mediating the anorectic effects of amylin and CGRP. It remains to be clarified whether this effect is due to amylin and CGRP action on receptors within the AP/NTS region or peripheral receptors on afferent nerves projecting to the AP/NTS.

Evidence for a physiological role of central calcitonin gene-related peptide (CGRP) receptors in the control of food intake in rats

In the present study, we investigated the role of central calcitonin gene-related peptide (CGRP) and amylin receptors in mediating the anorectic effects of CGRP and amylin in rats chronically cannulated in the lateral brain ventricle. Intracerebroventricular (ICV) injection of the CGRP and amylin receptor antagonist CGRP(8-37) failed to influence the anorectic effects of peripherally injected CGRP and amylin. CGRP(8-37) alone, however, increased food intake in food deprived rats when administered 2 h before food presentation. Under the same experimental conditions, the more specific amylin receptor antagonists amylin(8-37) or AC 187 did not affect food intake. We therefore conclude, that CGRP is a physiological regulator of food intake within the central nervous system, acting at central CGRP receptors. Peripheral receptors, however, are likely to mediate the anorectic effects of peripherally administered amylin and CGRP.

Different influence of CGRP (8-37), an amylin and CGRP antagonist, on the anorectic effects of cholecystokinin and bombesin in diabetic and normal rats

Because previous studies had suggested that the anorectic effects of cholecystokinin (CCK) and bombesin (BBS) depend partly on the release of amylin or calcitonin gene-related peptide (CGRP), we investigated the influence of the amylin and CGRP receptor antagonist CGRP (8-37) on the anorectic effects of CCK and BBS in streptozotocin (STZ)-diabetic and nondiabetic rats. STZ-diabetic rats had significantly lower plasma amylin and insulin concentrations than nondiabetic control rats. Amylin (5 micrograms/kg or 2.5 micrograms/rat) injected IP at dark onset after 24-h food deprivation elicited an anorectic effect of similar extent in STZ-diabetic and control rats. Under similar conditions, CCK (0.25 and 2 micrograms/kg) and BBS (5 micrograms/kg) reduced food intake in both STZ-diabetic and nondiabetic rats. These effects were markedly attenuated by CGRP (8-37) (10 micrograms/kg) in non-diabetics but not in STZ-diabetic rats. It is concluded that part of the anorectic effects of CCK and BBS depend on the release of amylin from pancreatic B-cells.

Influence of meal composition on postprandial peripheral plasma concentrations of vasoactive peptides in man

In a randomized cross-over study healthy non-obese male human subjects received standardized isocaloric, isovolumetric meals consisting of either carbohydrate, protein or fat and a non-caloric control meal consisting of an equal volume of water. Peripheral venous plasma concentrations of calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP), and peptide YY (PYY) were measured pre- and postprandially. Plasma CGRP concentrations were lowered following the protein meal and following the fat meal, but remained unaltered after carbohydrate or water ingestion. Plasma VIP concentrations increased slightly following the carbohydrate meal and following water loading. The PYY concentrations increased after the protein and the carbohydrate meal and a slight rise was observed following fat ingestion. Water loading did not affect the plasma level of PYY. We conclude that the postprandial peripheral plasma concentrations of CGRP, VIP and PYY are dependent on the caloric meal composition. The VIP, but not the CGRP and PYY concentrations seem to be influenced by gastric distension. The physiological significance of the postprandial alterations in peripheral concentrations of these peptides is at present uncertain.

Peripherally administered calcitonin gene-related peptide decreases food intake in mice

Previously, calcitonin gene-related peptide (CGRP) decreased food intake when administered ICV but not when administered peripherally to rats. Amylin, which has a close structural homology to CGRP, reduced food intake administered IP at concentrations higher than those previously tested for CGRP. We examined the effects of higher doses of IP-administered CGRP on food intake. CGRP reduced food intake from 25 to 200 micrograms/kg in mice. CGRP did not reduce water intake and was not aversive in a two-bottle test. Using a lever press, CGRP was more effective at reducing milk consumption in prefed than in nonprefed mice. The effect of CGRP on food intake was not antagonized by the cholecystokinin A receptor antagonist, L364,718. These studies suggest a role for CGRP as a satiating factor.

Circadian anorectic effects of peripherally administered amylin in rats

The pancreatic peptide amylin (1 microgram/kg) injected intraperitoneally reduced cumulative food intake for up to 4 h in food-deprived (24 h) and non-deprived rats at various times of the day, i.e., at dark onset, in the middle of the dark phase, and at light onset. At none of these times did subdiaphragmatic vagotomy abolish the anorectic effect of amylin. Rather, vagotomy enhanced, by unknown mechanisms, amylin's anorectic effect in food-deprived rats at light onset and in the middle of the dark phase. In contrast to previous studies with older rats, amylin's anorectic effect was also observed when injected into nondeprived rats. The findings of the present study extend previous reports in that amylin's anorectic effect, not being abolished by abdominal vagotomy after intraperitoneal injection, can be elicited at different times of the day.

Resistance to aging-associated obesity in capsaicin-desensitized rats one year after treatment

Previous studies demonstrated reduced weight of abdominal white adipose tissue depots and of carcass fat in capsaicin-desensitized (Cap-Des) rats up to 8 months after treatment. The objective of the present study was to find out whether aging-associated obesity and hyperplasia of retroperitoneal white adipose tissue was prevented in older (13.5 months old) Cap-Des rats, one year after treatment with Cap (done when they were 1.5 months old). The prevalence of obesity is known to increase in rats by this age. Abdominal white adipose tissue depots weighed less in old Cap-Des rats, both epididymal (9% less) and retroperitoneal (30% less). The number of mature white adipocytes was 28% less in the retroperitoneal depot but was not significantly different in the epididymal depot. Adipocyte size was not different. Carcass fat was less, both total and as percent of body weight. Food intake was normal for their reduced body size. The exponential increase in retroperitoneal white adipose tissue weight characteristic of aging rats that are becoming obese was virtually absent in Cap-Des rats. We conclude that lack of function of capsaicin-sensitive afferent autonomic nerves, known to be destroyed in Cap-Des rats, results in an alteration in energy balance conducive to leanness. We suggest that the attenuated age-associated increase in circulating CGRP (derived mainly from capsaicin-sensitive nerves) in the Cap-Des rat results in a lower degree of aging-associated insulin-resistance, hence in a lesser degree of obesity.

Reduction of food intake in rats by intraperitoneal injection of low doses of amylin

The effect of amylin injected IP on food intake in rats of different age (7-9 weeks, 3 months, 15-18 months) was investigated. The possible site of amylin action was investigated using vagotomized rats. Lastly, the influence of food composition on amylin's effect was investigated. In 12-h food-deprived old rats, food intake was decreased significantly by amylin (1-10 micrograms/kg) when injected at the beginning of the dark phase. Although the anorectic effect of amylin occurred somewhat earlier at 10 micrograms/kg, no clear dose-response relationship was observed. The anorectic effect was most marked in the first 2 h after amylin injection and was compensated over 24 h. Amylin (1 and 5 micrograms/kg) did not reduce food intake in undeprived old rats. In young rats, amylin (0.1-1 microgram/kg) dose-dependently reduced food intake if rats were food-deprived for 24 h, but not when deprived for 12 h. Dissection of the common hepatic vagus branch did not block the anorectic effect of amylin (age of rats: 3 months). The effect tended to last longer in vagotomized rats. The anorectic effect of amylin did not depend on the presence of carbohydrates in the diet. Water intake was not affected by amylin in water-deprived rats. In conclusion, the anorectic effect of amylin was observed at much lower doses (minimal effective dose: 0.5 microgram/kg) than reported before. These doses are similar to anorectic doses of cholecystokinin, a physiological peripheral satiety agent.