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The objective of this study was to estimate the prevalence of inadequate usual nutrient intake among female university students. This was a cross-sectional study in which 119 students at a public university in the State of Sao Paulo, Brazil, completed 3-day estimated food records. These were analyzed for nutrient content, and intake distributions were determined. Nutrient intake distributions were estimated using the National Research Council method. For nutrients for which an Estimated Average Requirement has been established, the Estimated Average Requirement cutpoint method was used to determine the proportion of students with inadequate intake. The students' food records indicated inadequate intakes of folate (99%), zinc (47%), and copper (33%). For approximately 95% of the students in this study, calcium was less than the Adequate Intake. The results showed the need for improvement in dietary choices to minimize the prevalence of inadequate intake of folate, zinc, copper, and calcium in this group.

Neuropeptide W (NPW) is an endogenous ligand for G protein-coupled receptor 7 (GPR7). There are two forms of the peptide, designated as neuropeptide W-23 (NPW23) and neuropeptide W-30 (NPW30). In the current study we found that intracerebroventricular administration of NPW23 increased c-Fos immunoreactivity (1R) in a variety of brain sites, many of which are involved in the regulation of feeding. In particular, we noted that c-Fos IR levels were increased in hypocretin-expressing neurons in the perifornical region of the lateral hypothalamus (LH). We then studied whether injection of NPW23 into the paraventricular nucleus of the hypothalamus (PVN) and the LH increased food intake over a 24-h time period. Intra-PVN injection of NPW23 at doses ranging from 0.1 to 3 nmol increased feeding for up to 4 h, and doses ranging from 0.3 to 3 nmol increased feeding for up to 24 h. In contrast, only the 3-nmol dose of NPW23 increased feeding after administration into the LH. Together, these data suggest a modulatory role for NPW in the control of food intake. ingestive behavior; c-Fos

Glucagon-like peptide-1(7-36)-amide (GLP-1) is postulated to act as a hormonal signal from gut to brain to inhibit food intake and gastric emptying. A mixed-nutrient meal produces a 2 to 3-h increase in plasma GLP-1. We determined the effects of intravenous infusions of GLP- 1 on food intake, sham feeding, and gastric emptying in rats to assess whether GLP-1 inhibits food intake, in part, by slowing gastric emptying. A 3-h intravenous infusion of GLP-1 (0.5-170 pmol*[kg.sup.-1]*[min.sup.-1]) at dark onset dose-dependently inhibited food intake in rats that were normally fed with a potency (mean effective dose) and efficacy (maximal % inhibition) of 23 pmol*[kg.sup.-1]*[min.sup.-1] and 82%, respectively. Similar total doses of GLP-1 administered over a 15-min period were less potent and effective. In gastric emptying experiments, GLP-1 (1.7-50 pmol*[kg.sup.-1]*[min.sup.-1]) dose-dependently inhibited gastric emptying of saline and ingested chow with potencies of 18 and 6 pmol*[kg.sup.-1]*[min.sup.-1] and maximal inhibitions of 74 and 83%, respectively. In sham-feeding experiments, GLP-1 (5 50 pmol*[kg.sup.-1]*[min.sup.-1]) dose-dependently reduced 15% aqueous sucrose intake in a similar manner when gastric cannulas were closed (real feeding) and open (sham feeding). These results demonstrate that intravenous infusions of GLP-1 dose-dependently inhibit food intake, sham feeding, and gastric emptying with a similar potency and efficacy. Thus GLP-1 may inhibit food intake in part by reducing gastric emptying, yet can also inhibit food intake independently of its action to reduce gastric emptying. It remains to be determined whether intravenous doses of GLP-1 that reproduce postprandial increases in plasma GLP-1 are sufficient to inhibit food intake and gastric emptying. satiety; dose-response; meal size; meal frequency

When neuropeptide Y (NPY) is administered centrally, meal-anticipatory responses are elicited. If an increase of endogenous NPY is a signal that heralds an imminent large caloric load, timed daily NPY injections may be expected to condition meal-anticipatory responses that facilitate ingestion. Rats received 4-h access to food beginning in the morning and then timed (1600 h), daily third-ventricular injections of NPY or saline for 7 days. On test day (day 8), animals received the conditioning drug (NPY or saline) or the opposite drug. Food was available immediately after injection on test day, and intake was measured. Rats conditioned with NPY and then given saline ate significantly more than rats conditioned with saline and then given saline; they ate the same amount as rats given NPY. Although they ate more, rats trained with NPY did not have changed plasma glucose, insulin, or ghrelin. These data suggest that NPY plays a role in mediating conditionable food-anticipatory responses that help to cope with the effects of large caloric loads. conditioning; learning; food intake

Attempts to understand ingestion have sought to understand the control of meals. The present study evaluated a meal definition that included prandial drinking (drinking-explicit meals). The spontaneous nocturnal intake of male Wistar rats was studied. The meal breakpoint was defined as the interval between feeding or drinking events providing the most stable estimate of meal structure. Alternative breakpoints derived from prevailing methodology, log-survivorship, or frequency histogram analysis of interfeeding intervals without respect to drinking were compared (drinking-naive meals). Threshold interfeeding intervals that accounted for drinking indirectly were evaluated as surrogate breakpoints (drinking-implicit meals). Definitions were compared by determining which criterion better conformed to predictions of satiety. Microstructural differences resulting from the definitions were also studied. Under the drinking-explicit definition, rats averaged nine or ten 13-min meals/night, during which they consumed food and water equally in duration (5-6 min) and quantity (2.3 g). Individual differences were observed in microstructure measures. Meals defined by drinking-informed, but not drinking-naive, methods were followed by the behavioral satiety sequence and by an initially low likelihood of resuming feeding that monotonically increased with time. The drinking-explicit definition uniquely revealed preprandial and postprandial correlations of similar magnitude. Under drinking-informed definitions, food restriction increased meal size, whereas drinking-naive definitions increased meal frequency. Drinking-implicit definitions provided workable approximations of meal frequency and size but inferior estimates of feeding duration, eating rate, and the preprandial correlation. Thus log-survivorship analysis is not appropriate for identifying meal breakpoints, and the consideration of drinking in meal definitions can provide a better estimate of meal structure. feeding or drinking; food-associated drinking; meal size or duration; eating rate; intermeal interval; behavioral satiety sequence; bout microstructure analysis; meal pattern analysis; satiation

We previously reported that [sup.2][H.sub.2]O can be used to measure rates of protein synthesis during prolonged steady-state conditions (Previs SF, Fatica R, Chandramouli V, Alexander JC, Brunengraber H, and Landau BR. Am J Physiol Endocrinol Metab 286: E665-E672, 2004). The underlying premise of our method is that following the administration of [sup.2][H.sub.2]O, [sup.2]H atoms in body water rapidly equilibrate with free alanine before it is incorporated into newly synthesized proteins. We have now directly examined whether [sup.2][H.sub.2]O can be used to measure the influence of a single meal on protein synthesis. In addition, we have compared the use of [sup.2][H.sub.2]O for measuring rates of protein synthesis in vivo vs. in cell culture. Using a rat model, we observed rapid equilibration between [sup.2]H in body water and free alanine; therefore we were able to study the response of protein synthesis to a single meal. We observed that ~50% of the plasma albumin that is synthesized over the course of 24 h is made within ~5 h after eating (in rats trained to eat a complete 24-h ration of food in a single meal). Contrary to what we observed in vivo, feeding (the replenishment of cell culture medium) does influence the use of [sup.2][H.sub.2]O for in vitro studies. In particular, since there can be slow equilibration of [sup.2]H between water and alanine in the cell culture medium, special consideration must be made to avoid underestimating the rate of protein synthesis in vitro. albumin turnover; nutritional status; stable isotopes; gas chromatography-mass spectrometry

Intermedin (IMD)/adrenomedullin-2 (AM2) is a novel peptide that was independently discovered by two groups. The 47-amino acid peptide is homologous to adrenomedullin (AM) and can activate both the AM and calcitonin gene-related peptide (CGRP) receptors. IMD should therefore have actions similar to those of AM and CGRP. Indeed, like AM and CGRP, intravenous administration of IMD decreased blood pressure in rats and mice. We demonstrate here that immunoreactive IMD is present in plasma as well as heart, lung, stomach, kidney, pituitary, and brain. Because IMD is present in brain and both AM and CGRP have potent central nervous system (CNS) effects, we examined the ability of IMD within brain to regulate blood pressure and ingestive behaviors. Administration of IMD into the lateral cerebroventricle of rats caused significant, long-lasting elevations in mean arterial pressure and heart rate. These elevations are similar to the effects of CGRP and significantly greater than the effects of AM. IMD-induced elevations in mean arterial pressure were inhibited by intravenous administration of phentolamine, indicating that IMD activates the sympathetic nervous system. Intracerebroventricular administration of IMD also inhibited food and water intake in sated and in food- and water-restricted animals. The effects on feeding are likely related to activation of the CGRP receptor and are independent of the effects on water intake, which are likely through the AM receptor. Our data indicate that IMD has potent actions within the CNS that may be a result of the combined activation of both AM and CGRP receptors. calcitonin gene-related peptide; heart rate; brain

Byline: Aydin Yagmurlu (1), Burhan Aksu (1), Meltem Bingol-Kologlu (1), Nurten Renda (2), Gulcin Altinok (3), Suat Fitoz (4), I. Haluk Gokcora (1), Huseyin Dindar (1) Keywords: Caustic ingestion; Esophageal stricture; Sphingolipids; Sphingosylphosphorylcholine; Wound healing Abstract: Using a new class of intracellular 2nd messengers to prevent stricture formation after caustic ingestion, sphingosylphosphorylcholine (SPC) has a wide spectrum of activity in cell growth regulation and signal transduction. Caustic esophageal burns were created with 15% NaOH in an experimental rat model. Control group animals (n=10) had esophageal burns with no treatment, whereas the SPC group (n=10) had esophageal burns gavaged with SPC for 7 days. Efficacy of treatment was assessed in 28 days by contrast esophagograms, histopathologic evaluation, and biochemically by tissue hydroxyproline (OHP) content. Contrast esophagograms demonstrated that SPC significantly prevented stricture formation. Obvious collagen deposition was present in submucosa, muscularis mucosa, and muscular layers in the control group compared with the SPC group. The damage to the esophageal wall on histopathologic examination was significantly lower in the SPC group (p&lt 0.05). Tissue OHP contents were significantly lower in the SPC-treated group (3.0+-0.1 ug/mg) compared with the control group (4.3+-0.2 ug/mg) (p&lt 0.05). We conclude that SPC improves healing following caustic esophageal burns. Furthermore, SPC is effective in preventing caustic esophageal strictures. These effects of SPC occur through its proliferative and specifically its remodeling effects on wound healing. Author Affiliation: (1) Department of Pediatric Surgery, Ankara University, School of Medicine, Gumus Cad. D-14.4 Konutkent--1 06530, Ankara, Turkey (2) Department of Biochemistry, Hacettepe University, Faculty of Medicine, Ankara, Turkey (3) Department of Pathology, Hacettepe University, Faculty of Medicine, Ankara, Turkey (4) Department of Radiology, Ankara University, School of Medicine, Ankara, Turkey Article History: Registration Date: 15/01/2004 Accepted Date: 17/12/2002 Online Date: 05/06/2004

Through a multiplex promoter spanning 218 kb, the phase II UDP-glucuronosyltransferase 1A (UGT1) gene encodes at least eight differently regulated mRNAs whose protein products function as the principal means to eliminate a vast array of steroids, heme metabolites, environmental toxins, and drugs. The orphan nuclear receptors pregnane X receptor (PXR) and constitutive androstane receptor (CAR) were originally identified as sensors able to respond to numerous environmentally derived foreign compounds (xenobiotics) to promote detoxification by phase I cytochrome P450 genes. In this report, we show that both receptors can induce specific UGT1A isoforms including those involved in estrogen, thyroxin, bilirubin, and carcinogen metabolism. Transgenic mice expressing a constitutively active form of human PXR show markedly increased UGT activity toward steroid, heme, and carcinogens, enhanced bilirubin clearance, as well as massively increased steroid clearance. The ability of PXR and constitutive androstane receptor and their ligands to transduce both the phase I and phase II adaptive hepatic response defines a unique transcriptional interface that bridges the ingestion and metabolism of environmental compounds to body physiology.

By using a combination of genetic, pharmacological, and anatomical approaches, we show that the melanocortin 4 receptor (MC4R), implicated in the control of food intake and energy expenditure, also modulates erectile function and sexual behavior. Evidence supporting this notion is based on several findings: (i) a highly selective non-peptide MC4R agonist augments erectile activity initiated by electrical stimulation of the cavernous nerve in wild-type but not Mc4r-null mice; (ii) copulatory behavior is enhanced by administration of a selective MC4R agonist and is diminished in mice lacking Mc4r; (iii) reverse transcription (RT)-PCR and non-PCR based methods demonstrate MC4R expression in rat and human penis, and rat spinal cord, hypothalamus, brainstem, pelvic ganglion (major autonomic relay center to the penis), but not in rat primary corpus smooth muscle cavernosum cells; and (iv) in situ hybridization of glans tissue from the human and rat penis reveal MC4R expression in nerve fibers and mechanoreceptors in the glans of the penis. Collectively, these data implicate the MC4R in the modulation of penile erectile function and provide evidence that MC4R-mediated proerectile responses may be activated through neuronal circuitry in spinal cord erectile centers and somatosensory afferent nerve terminals of the penis. Our results provide a basis for the existence of MC4R-controlled neuronal pathways that control sexual function.

GLP-1 receptor signaling contributes to anorexigenic effect of centrally administered oxytocin in rats. Am J Physiol Regulatory Integrative Comp Physiol 283: R99-R106, 2002. First published March 29, 2002; 10.1152/ajpregu.00008.2002.--The present study examined possible interactions between central glucagon-like peptide-1 (GLP-1) and oxytocin (OT) neural systems by determining whether blockade of GLP-1 receptors attenuates OT-induced anorexia and vice versa. Male rats were acclimated to daily 4-h food access. In the first experiment, rats were infused centrally with GLP-1 receptor antagonist or vehicle, followed by an anorexigenic dose of synthetic OT. Access to food began 20 rain later. Cumulative food intake was measured every 30 min for 4 h. In the second experiment, rats were infused with OT receptor blocker or vehicle, followed by synthetic GLP-1 [(7-36) amide]. Subsequent food intake was monitored as before. The anorexigenic effect of OT was eliminated in rats pretreated with the GLP-1 receptor antagonist. Conversely, GLP-l-induced anorexia was not affected by blockade of OT receptors. In a separate immunocytochemical study, OT-positive terminals were found closely apposed to GLP-l-positive perikarya, and central infusion of OT activated c-Fos expression in GLP-1 neurons. These findings implicate endogenous GLP-1 receptor signaling as an important downstream mediator of anorexia in rats after activation of central OT neural pathways. food intake; paraventricular nucleus of the hypothalamus; dorsal vagal complex

Principles for interactions among the multiple systems that influence food intake. Am J Physiol Regulatory Integrative Comp Physiol 283: R46-R53, 2002; 10.1152/ajpregu.00021.2002.--The widespread use of molecular biological has led to a pronounced increase in the number of signals that are now implicated in the controls of food intake and body weight. However, a complete understanding of the roles of these multiple signals requires that we assess how they interact with one another to alter ingestive behavior. Although many such experiments are being conducted, methods employed to delineate these interactions are often fraught with interpretive difficulties. The purpose of this article is to explore these difficulties and offer practical advice for minimizing these issues in experiments that seek to explore the important interactions among these signals. In particular, the issues of additive vs. nonadditive results, the use of sub- or suprathreshold dose combinations, and the choosing of multiple-dose analyses are all addressed. Furthermore, the possibilities of using intake measures other than cumulative intake and complementary nonbehavioral endpoints are encouraged. dose-effect curve; leptin; multiple-dose combination; obesity; peptide

This review focuses on what is known about the effects of carbohydrate on food intake, the potential mechanisms mediating these effects, and the impact of different monosaccharides in humans. The inhibition of subsequent food intake associated with ingestion of carbohydrate appears to result primarily from gastrointestinal signals, including those generated by orosensory stimulation, gastric distension, and perhaps most importantly the interaction of nutrients with receptors in the small intestine. The latter is associated with the release of putative satiety hormones, including glucagon-like peptide-1 and amylin, and slowing of both gastric emptying and small intestinal transit (thereby prolonging gastric distension and increasing the time available for nutrient absorption). The effects of carbohydrate on food intake are dependent on the route of administration (i.e., oral, intragastric, or intraduodenal). Changes in blood glucose and insulin concentrations per se probably do not play a major role in the induction of satiety. Studies relating to the comparative effects of different monosaccharides/carbohydrates have yielded inconclusive results, probably in part owing to substantial differences in methodological approaches. Key Words: carbohydrate, food intake, gastrointestinal signals, glucagon-like peptide-1, satiety

We previously demonstrated that amylin inhibits food intake and gastric emptying in rats with half-maximal effective doses (E[D.sub.50]s) of 8 and 3 pmol*[kg.sup.-1]*[min.sup.-1] and maximal inhibitions of 78 and 60%, respectively. In this study of identical design, rats received intravenous infusions of salmon calcitonin (sCT), rat calcitonin (rCT), rat calcitonin gene-related peptide (rCGRP), and rat adrenomedullin (rADM) for 3 h at dark onset, and food intake was measured for 17 h or for 15 min and gastric emptying of saline was measured during the final 5 min. sCT, rCGRP, and rADM inhibited food intake with estimated E[D.sub.50]s of 0.5, 26, and 35 pmol*[kg.sup.-1]*[min.sup.-1] and maximal inhibitions of 88, 90, and 49%, respectively, rCT was not effective at doses up to 100 pmol*[kg.sup.-1]*[min.sup.-1]. sCT, rCGRP, rADM, and rCT inhibited gastric emptying with E[D.sub.50]s of 1, 130, 160, and 730 pmol*[kg.sup.-1]*[min.sup.-1] and maximal inhibitions of 60, 66, 60, and 33%, respectively. These results suggest that amylin and sCT may act by a common mechanism to decrease food intake, which includes inhibition of gastric emptying. calcitonin; calcitonin gene-related peptide; adrenomedullin; anorexia; potency

Midlife weight gain occurs in many species, suggesting that leptin signaling is impaired at middle age. To test this hypothesis, we measured changes in food intake and body composition in young (Y) and middle-aged (MA) C57BL/6 male mice infused subcutaneously with phosphate-buffered saline or leptin. Leptin-induced decreases in food intake and body fat were delayed in MA mice and associated with catabolism after longer treatment periods. Endogenous plasma leptin levels did not correlate with body fat in MA mice. Calorie restriction (CR) reduced body fat, plasma leptin, and insulin in MA mice to levels in Y mice but did not upregulate leptin sensitivity. CR mice did not respond to leptin doses that inhibited food intake in MA mice and reduced food intake and body fat in Y mice significantly below levels in CR mice. Plasma corticosterone was significantly higher in leptin-treated CR vs. MA mice. We conclude that MA C57BL/6 mice exhibit impaired leptin signaling and that CR, possibly by elevating glucocorticoids, impairs appetite control without improving the metabolic actions of leptin. weight gain; food intake; glucocorticoids; insulin; longevity

There has been much debate about the effect of postprandial glucose levels on diabetes outcomes and the necessity of treating postprandial hyperglycemia in patients with type 2 diabetes. Current recommendations [...]

Ingestive behavior and body temperature during the ovarian cycle in normotensive and hypertensive rats. Am J Physiol Regulatory Integrative Comp Physiol 282: R216-R225, 2002; 10.1152/ajpregu.00676.2000.--The relationship between ingestive behavior (eating + drinking) and core body temperature ([T.sub.b]) in naturally cycling female rats was compared in a normotensive strain (Sprague-Dawley; SD) and a hypertensive strain reputed to have chronically elevated [T.sub.b] (spontaneously hypertensive rats; SHR). [T.sub.b] (by telemetry) and ingestive behavior (automated recording) were quantified every 30 s. Ingestive behavior and [T.sub.b] were related on all days of the ovarian cycle in both strains, but the strength of that relationship was reduced on the day of estrus (E) compared with nonestrous days. Several strain differences in [T.sub.b] were found as well. In SHR, dark-phase [T.sub.b] was elevated on E, whereas SD remained at the lower nonestrous values. Fluctuations in dark-phase [T.sub.b] were correlated with ingestive behavior in both strains but had greater amplitude in SHR except on E. Short-term fasting or sucrose availability did not eliminate elevated dark-phase [T.sub.b] on E in SHR. We propose that estrus-related changes unique to SHR may indicate heightened thermal reactivity to hormonal changes, ingestive behavior, and general locomotor activity. spontaneously hypertensive rat; Sprague-Dawley rat; estrus; telemetry; feeding; drinking; fasting; sucrose

Riediger, Thomas, Herbert A. Schmid, T. Lutz, and E. Simon. Amylin potently activates AP neurons possibly via formation of the excitatory second messenger cGMP. Am J Physiol Regulatory Integrative Comp Physiol 281: R1833-R1843, 2001.--Amylin is secreted with insulin from the pancreas during and after food intake. One of the most potent actions of amylin in vivo is its anorectic effect, which is directly mediated by the area postrema (AP), a circumventricular organ lacking a functional blood-brain barrier. As we recently demonstrated, amylin also stimulates water intake most likely via its excitatory action on subfornical organ (SFO) neurons. Neurons investigated under equal conditions in an in vitro slice preparation of the rat AP were 15-fold more sensitive to amylin than SFO neurons. Amylin ([10.sup.-11]-[10.sup.8] M) excited 48% of 94 AP neurons tested; the remaining cells were insensitive. The average threshold concentration of the excitatory response was [10.sup.-10] M and, thus, close to physiological plasma concentrations. Coapplication of the amylin receptor antagonist AC-187 reduced amylin's excitatory effect. Amylin-mediated activation of AP neurons and antagonistic action of AC-187 were confirmed in vivo by c-fos studies. Peripherally applied amylin stimulated cGMP formation in AP and SFO neurons, as shown in immunohisto-chemical studies. This response was independent of nitric oxide (NO) formation in the AP, while coapplication of the NO synthase inhibitors N-monomethyl-L-arginine (100 mg/ kg) and nitro-L-arginine methyl ester (50 mg/kg) blocked cGMP formation in the SFO. In contrast to the SFO, where NO-dependent cGMP formation seems to represent a general inhibitory transduction pathway, cGMP acts as an excitatory second messenger in the AP, since the membrane-permeable analog 8-bromo-cGMP stimulated 65% of all neurons tested (n = 17), including seven of nine amylin-sensitive neurons (77%). The results indicate that the anorectic effect of circulating amylin is based on its excitatory action on AP neurons, with cGMP acting as a second messenger. food intake; water intake; electrophysiology; nitric oxide; subfornical organ Received 12 March 2001; accepted in final form 27 July 2001

Aja, Susan, Shirin Sahandy, Ellen E. Ladenheim, Gary J. Schwartz, and Timothy H. Moran. Intracerebro-ventricular CART peptide reduces food intake and alters motor behavior at a hindbrain site. Am J Physiol Regulatory Integrative Comp Physiol 281: R1862-R1867, 2001.--Peptides from cocaine- and amphetamine-regulated transcript (CART) reduce food intake in rats when injected into the lateral ventricle. Hypothalamic and hindbrain sites important in the control of feeding contain CART-immunoreactive fibers. To further define the site of CART's anorectic action, we compared feeding and other behavioral responses to third or fourth ventricular (3V, 4V) CART-(55-102) in 6-h food-de-prived rats, both before and after cerebral aqueduct occlusion. 3V CART reduced the volume of Ensure consumed and resulted in fewer observations of eating and grooming within the 30-min test session. These reductions were significantly attenuated by aqueduct obstruction. 4V CART suppressed Ensure intake and resulted in decreased observations of feeding both with and without aqueduct blockade. 3V CART produced fiat-backed postures and movement-associated tremors that were prevented by aqueduct obstruction. 4V CART also produced these signs, both with and without aqueduct blockade. We conclude that the major hypophagic effect of intracerebroventricular CART is mediated at a hind-brain site. The association of CART-induced feeding suppression with altered motor behavior questions the specificity of intracerebroventricular CART for actions on feeding. cocaine- and amphetamine-regulated transcript feeding; hypothalamus Received 8 February 2001; accepted in final form 17 August 2001

This study was undertaken to determine whether casein, compared with its constituent amino acids, given at the onset of a meal, would influence intake due to cholecystokinin (CCK) or opioid activity. Male Sprague-Dawley rats (n = 80; 225 g) were given either premeal loads of casein or its constituent amino acids and treated with opioid or CCK antagonists in a 2 x 4 factorially designed experiment. During a 21-d period, rats were meal-fed by restricting access to food to 5 h/d. The rats were fed the AIN-93 diet with soy isolate substituted for casein as the dietary protein source. On d 7-21, rats were given oral premeal loads of 5 mL of a 50 g/L casein or constituent amino acid solution before meal-feeding. On d 14-21, 20 rats were injected intraperitoneally with one of the following treatments: saline, naltrexone (l mg/kg), naloxone methiodide (5 mg/kg) or lorglumide (1 mg/kg) before the premeal load and feeding. Antagonist treatments increased intake (P < 0.05) by 15.3% compared with saline treatment (7.82 vs. 9.02 g/d) in rats given premeal loads of casein. Intake of rats given premeal loads of amino acids was not influenced by antagonists. At 2 h after feeding on d 21, the rats were killed, bled and eviscerated. Effects of antagonists on stomach and intestinal mass, digesta contents and fecal output were also dependent on the type of premeal load, indicating that gastric retention of digesta due to casein was mediated by CCK and opioids. Body weight accretion, liver, and epididymal fat mass and blood concentrations of specific amino acids changed in the same manner as intake (P < 0.05). Serum insulin was greater (P < 0.05) in casein-treated rats and reduced (P < 0.01) by opioid antagonists. Satiety associated with premeal loads of casein is related to changes in gastrointestinal function of meal-fed animals and involves both opioid and CCK regulation. KEY WORDS: * intake * satiety * casein * opioids * cholecystokinin * rats

We examined the effect of daily consumption of dietary diacylglycerol (DG) oil on serum lipid concentrations in patients with diabetes whose serum triacylglycerol (TG) levels were persistently increased despite continuous nutritional counseling at the outpatient clinic. Patients (n = 16) were divided into DG and control groups (n = 8 each). DG was incorporated (target dose 10 g/d) by substituting DG oil (80 g DG/100 g oil) for the ordinary TG cooking oil used at home for 12 wk. The control group continued consuming ordinary TG cooking oil. Dietary records indicated that there were no differences between groups in total energy intake or percentage of energy from fat. In the DG group, TG intake decreased from 26.8 [+ or -] 9.3 to 15.7 [+ or -] 8.9 g/d, whereas DG intake increased from 0.3 [+ or -] 0.1 to 10.6 [+ or -] 3.9 g/d. No differences between groups were observed in body weight, total fat intake or total oil consumption throughout the study period. In the DG group, serum TG levels decreased 39.4% from 2.51 [+ or -] 0.75 mmol/L to 1.52 [+ or -] 0.28 mmol/L. Serum glycohemoglobin [A.sub.1c] (Hb[A.sub.1c]) concentration also decreased 9.7%. In contrast, there were no changes in these variables in the control group. Serum total and HDL cholesterol were not affected in either group. These results indicate that DG oil may be useful as an adjunct to the standard diet therapy of fat restriction in the management of diabetics with hypertriglyceridemia. KEY WORDS: * diacylglycerol * triacylglycerol * humans * diabetes * hypertriglyceridemia

Research has been conducted on the food intake seasonal pattern and the tissue energy status of the Antarctic echinoid Sterechinus neumayeri. Results indicate that the seasonality of the food intake does not affect significantly the energy status of these sea urchins.

The rate of food detection and the magnitude of temperature drops are higher in the oesophagus than in the stomach of captive penguins. Data indicate that the magnitude of temperature drops is positively correlated to the mass of a single, ingested prey.

Objective: To assess food behavior and determine nutritional intakes of various vegetarian populations in France. Design: A five-day self-administered food record which was mailed to members of the three principal French vegetarian organisations. Subjects: 145 subjects, aged 7-87 y; 94 classical vegetarians (19% of those contacted), 34 Hindu lactovegetarians (17% of those contacted) and 17 macrobiotic (34% of those contacted). Setting: The survey was conducted between March 1997 and July 1997 in France. Results: Vegetarianism in France is represented by three main classes of food behaviour: ovolactovegetarian (AAV), lactovegetarian (KRI) and macrobiotic (MMK). The geometric mean intakes ranged from 1952 kcal/d (KRI), 2051 kcal/d (MMK) to 2384 kcal/d (AAV) for males and from 1302 kcal/d (MMK), 1675 kcal/d (AAV) to 1804kca1/d (KRI) for females, after adjusting for age and BMI. The energy consumption in the MMK group was significantly lower than that in the AAV (P < 0.05) and KRI groups (P < 0.01), respectively. A difference among groups was observed for females (P = 0.0002), but not for males. The MMK group consumed less lipid than the other two vegetarian groups, 46 g/d for men and 38 g/d for women vs 80 g/d for men and 61 g/d for women in the AAV group and 93 g/d for men and 81 g/d for women in the KRI group, respectively. Differences with AAV and MMK were statistically significant (P < 0.001 for men and women for both groups). Mean protein consumption ranged from 60 g/d (AAV), 64 g/d (KRI) to 77 g/d (MMK) for males and from 46 g/d (MMK), 50 g/d (AAV) to 58 g/d (KRI) for females. Mean carbohydrate intakes ranged from 247 g/d (AAV), 321 g/d (KRI) to 338 g/d (MMK) in males and from 209 g/d (MMK), 228 g/d (AAV) to 242 g/d (KRI) in females. There were no significant differences in protein and carbohydrate intakes between the groups. Median calcium intakes ranged from 758.2 mg/d (MMK), 863 mg/d (AAV) to 989.3 mg/d (KRI) for the men and from 500.8 mg/d (MMK), 863 mg/d (AAV) to 934 mg/d (KRI) for the women. In the men, there was no differences in daily calcium intakes between the three vegetarian groups. However, we found a significant difference for women (P = 0.0041). The women in the MMK group presented significantly lower daily calcium intakes than the women in the AAV (P=0.013) and KRI (P=0.0032) groups. The AAV and KRI groups consumed dairy products supplying respectively 36% and 53% for the men and 39% and 59% for the women of total calcium against 0% for men and women in the MMK group. Median iron intakes ranged between 12.5 mg/d (KRI), 13.2 mg/d (AAV) and 22.5 mg/d (MMK) for the men and between 11.2 mg/d (KRI), 14.6 mg/d (AAV) and 16.9 mg/d (MMK) for the women. MMK (men P = 0.0172 and women P = 0.0131) and AAV (only in men P = 0.037) groups consumed significantly higher quantities of iron than did the KRI group. The heme iron median intake in males and females of the three vegetarian groups was very low (< 0.5%). Overall, the female vegetarians consumed 58.1 (MMK), 109 (AAV) and 127.4 (KRI) mg of vitamin C per day and the males 76.3 (MMK), 150.4 (AAV) and 150.4 (KRI) mg per day. Median vitamin B9 intakes ranged from 247.5 [micro]g/d (KRI), 312 [micro]g/d (MMK) to 390.4 [micro]g/d (AAV) for the men and from 188.3 [micro]g/d (MMK), 266.9 [micro]g/d (KRI) to 323.8 [micro]g/d (AAV) for the women. Vitamin B12 consumption ranged from 0.2 [micro]g/d (MMK), 1.5 [micro]g/d (AAV) to 1.7 [micro]g/d (KRI) in the women and from 0.6 [micro]g/d (MMK) to 1.0 [micro]g/d (AAV and KRI) in the men. No differences in consumption were observed in the males. On the other hand, the women in the MMK group consumed significantly less vitamin C and B12 than did the women in the AAV (P = 0.0006) and KRI (P=0.0396) groups, while it was at the limit of significance for the females (P=0.0715) for vitamin B9. Conclusion: Our results suggest that vegetarians have a better understanding of dietary requirements than does the general population. We observed that the more restrictive the vegetarian diet, the more likely were there to be deficiencies in minerals and vitamins, especially heme iron, diary calcium and vitamin B12 intakes. This was a particularly true for macrobiotic diets and especially for women, which represents a group at particular risk for mineral and vitamin deficiency. Sponsorship: The study was sponsored by a non-profit organisation (Vegetarian association, Center of Nutritional Information Research, Center of Meat Information) and was coordinated by the Center of Foch Research. Descriptors: vegetarian; food behaviour; nutritional intakes; 5-day diet records, Introduction Food choice behaviour enables us to ingest what we need in order to avoid nutrition-related deficiencies and pathologies (Louis-Sylvestre, 1987). However, certain factors, such as food fads and restrictive [...]

Experiments were performed on six groups of rats to test the hypothesis that progressive increase in sham intake is concentration dependent. The rats were given five sham feeding tests with six different concentrations of sweetened condensed milk. The intake of concentrated solutions of milk was found to be limited by two negative feedback signals, while the intake of weak of concentrations was limited only by a nonlabile negative feedback signal. These results indicate that the hypothesis is wrong.

Research was conducted to determine whether intraperitoneal injection or intraportal infusion of 2-mercaptoacetate affects the hepatic membrane potential in rats in vivo. The liver cell membrane potential was measured in anesthetized Sprague-Dawley rats with the microelectrode method. Results were in agreement with the potentiostatic hypothesis, suggesting a connection between the hepatic membrane potential, afferent vagal activity and the control of food intake.

Leptin regulates energy balance through its actions in the brain on appetite and energy expenditure and also shares properties with cytokines such as IL-1. We report here that leptin, injected into rats intracerebroventricularly or peripherally, induces significant dose-dependent increases in core body temperature as well as suppression of appetite. Leptin failed to affect food intake or body temperature in obese (fa/fa) Zucker rats, which posses a defective leptin receptor. Furthermore, injection of leptin increased levels of the proinflammatory cytokine IL-1[Beta] in the hypothalamus of normal Sprague-Dawley rats. Central injection of IL-1 receptor antagonist (IL-1ra) inhibited the suppression of food intake caused by central or peripheral injection of leptin (60 and 84%, respectively) and abolished the leptin-induced increase in body temperature in both cases. Mice lacking (gene knockout} the main IL-1 receptor (80 kDa, R1) responsible for IL-1 actions showed no reduction in food intake in response to leptin. These data indicate that leptin actions in the brain depend on IL-1, and we show further that the effect of leptin on fever, but not food intake, is abolished by a cyclooxygenase inhibitor. Thus, we propose that in addition to its role in body weight regulation, leptin may mediate neuroimmune responses via actions in the brain dependent on release of IL-1 and prostaglandins.

High exposures to fluoride ([F.sup.-]) may occur in environments rich in [F.sup.-] from natural or industrial sources and from misuse of [F.sup.-]-containing dental care products, particularly by children. Both acute and chronic exposures to elevated levels of [F.sup.-] have negative effects on several calcium-dependent processes, including kidney glomerular and tubular function. We examined the effect of chronic [F.sup.-] ingestion on ATP-dependent 45Ca uptake by rat kidney membrane vesicles to characterize the mechanism by which high [F.sup.-] alters [Ca.sup.++] transport in the kidney. Twenty weanling female Sprague-Dawley rats were raised on low-[F.sup.-] (0.9 mg/L), semi-purified diet with a [Ca.sup.++] concentration of 400 mg/100g diet. Rats were divided into four groups and were fed ad libitum deionized water containing [F.sup.-] at 0, 10, 50, or 150 mg/L added as NaF for 6 wk. This consumption produced plasma [F.sup.-] levels of KEY WORDS: [Ca.sup.++]transport; fluoride; [Ca.sup.++]-pump; endoplasmic reticulum [Ca.sup.++]-pump; plasma membrane [Ca.sub.++] -pump; rats

A study was conducted to analyze the involvement of central corticotropin-releasing factor (CRF) receptors in the initiation of chronic response to acute stress in rats. Feed efficiency ratio was determined by dividing weight change during the experimental period by total volume of food consumed during the period. Results indicated that CRF receptors located in or near the hypothalamus mediate the acute responses to stress that lead to a permanent change in the hormonal or metabolic processes that determine body composition and weight.

A study was conducted to analyze the effects of orchiectomy and testosterone replacement on the association between meal number and size and changes in resulting feeding patterns in male rats. The feeding indexes were examined separately for 24 hours for light-phase and dark-phase feeding. Results indicated that androgens immediately influence the meal number-to-meal size relationship and that the influence of testosterone on food intake may also occur partially through a nongenomic effect.

Underreporting of habitual food intake can be explained by underrecording and/or undereating. This study was designed to discriminate between the two errors mentioned, by measuring energy and water balance. Twenty-four lean female dieticians were recruited as subjects. Energy intake and water intake were measured for 1 wk with a weighed dietary record. Energy expenditure was estimated from measurements of resting metabolic rate, and measured physical activity with a triaxial accelerometer for movement registration. Water loss was estimated with deuterium-labeled water. Energy balance was determined by measuring the change in body mass over a nonrecording week (preceding the recording week) and over the recording week. Mean energy and water intake were 8.5 [+ or -] 1.0 MJ/d and 2.3 [+ or -] 0.5 L/d. The change in body mass in the nonrecording week was 0.1 [+ or -] 0.6 kg and in the recording week -0.6 [+ or -] 0.8 kg (paired t test; P = 0.02), indicating 16% undereating. Recorded water intake plus calculated metabolic water closely matched measured water loss (r = 0.93; P = 0.0001), which indicated a high recording precision. In conclusion, in the studied group of highly motivated lean women, there was 16% underreporting of habitual food intake, which could be explained by undereating. KEY WORDS: energy-intake; water-intake; energy-balance; water-balance; women

Conjugated linoleic acid rapidly and significantly reduces fat accumulation and increases protein accumulation at relatively low doses without compromising food intake. This was gleaned from an experiment in which mice were subjected to conjugated linoleic acid feeding to determine a dose of the acid that would have effects on body composition without affecting energy intake. Results show that higher doses of conjugated linoleic acid substantially increased carcass protein content without suppressing energy intake.

The changes in feeding patterns underlying decreased food intake near the end of life of rats are described. The nine male rats whose meal patterns associated with age-related decline in food intake exhibited a similar pattern of decreased food intake. While they ate smaller meals, there was no difference in the number of meals they ate per day. Their selection of preferred diets was not affected by rapid weight loss.

Infusion of angiotensin II into the brain ventricles stimulated both water intake and sodium chloride intake in baboons. The infusion of the angiotensin-receptor antagonist losartan by the same route inhibited the water intake after water deprivation. The infusion of ZD-7155 inhibited the sodium chloride intake after sodium depletion. The peripheral administration of captopril also reduced the sodium chloride intake after sodium depletion.

Experiments were performed to test the hypothesis that an inverse relationship occurs between food intakes and increasing loads of nutrients into the gut or instilled into the stomach because higher loads of nutrients contacted longer lengths of small intestine to excite additive feedbacks from more and more sensors along the bowel. Results showed that food intake was inhibited by intestinally perfused nutrients along the proximal and distal segments of the intestine.

The origin and onset of hyperphagia in the Zucker fatty (fa/fa) rat were determined by studying the ingestion in preweanling rats independent of the dam. Results showed that fa/fa rats ingested significantly more than their lean littermates as early as day 12. While the experiment indicates that hyperphagia in fa/fa pups occurs between the ages P9 and P12, other stimulus may result in different emergence of hyperphagia in fa/fa rats.

The consequences of enterostatin in rats that were adapted to either a high-fat (HF) or high-carbohydrate/low-fat (HC) diet and then exposed to either HF or HC diets were investigated. Results showed that chronic intake of dietary fat is needed for enterostatin action and that chronic ingestion of fat starts a postingestion metabolic, endocrine or neurochemical change that is needed for the biological response to enterostatin.

Lesions of the most posterodorsal aspects of the amygdalia in female rats cause hyperphagia and moderate obesity. Rats with amygdaloid lesions did not increase their daily food consumption whn their powdered diet was diluted with 25 or 50% nonnutritive bulk. Findings, when taken into account with the previous observation that identical lesions cause hyperinsulinemia, show that the amygdala is involved in both the homeostatic regulation of food intake and the choice of macronutrients.

Inhibition of a signal that generates positive energy balance involving neuropeptide Y (NPY) projection from arcuate nucleus to paraventricular nucleus is a possible mechanism for leptin action. It is hypothesized that reduced NPY activity is needed for the satiety and thermogenic effects of leptin. Findings showed that repletion of NPY in the paraventricular nucleus by specific NPY microinjection reverses the feeding-inhibitory and thermogenic effects of centrally administered leptin.

Six men and six women were given a medium fat maintenance breakfast on day 1 and a high-fat breakfast on day 2 to determine the effect of isoenergetically-dense doses of dietary 1-monoglyceride or triglyceride on appetite and meal-to-meal energy intake in man. Results showed that fat type had no significant effect on food or energy intake at lunch or throughout the rest of the day. This suggests that a large dose of 1-monoglyceride or triglyceride added to a breakfast meal has the same effect on hunger, appetite or feeding behavior as triglyceride.