The effects of chronic (40%) food restriction from 6 weeks of age were studied in aging male Fisher 344 rats. When compared with 3-month-old, ad libitum fed rats, pineal N-acetyltransferase (NAT) activity had declined to less than 30% and pineal and serum levels of melatonin to 40% after 28 months ...

In order to study the regulation of food intake and correlated body energy metabolism, the effect of restricted feeding during the light period in female IVCS mice was investigated. Access to food and water was restricted (RF group) for 3 weeks only from 10:00 hr to 17:00 hr, and that ...

Male rats that exercise in running wheels have a longer average survival than freely eating sedentary controls but, in contrast to food-restricted sedentary controls of the same weight, show no extension of maximal life span (J. Appl. Physiol. 59: 826-831, 1985). To test the possibility that exercise may counteract a ...

The effect of food restriction (60% of an ad lib ration) for the first 14 days postpartum on serum progesterone levels and the duration of lactational diestrus was determined in rat dams nursing litters of eight pups. Food restricted dams showed a longer period of lactational diestrus than ad lib ...

This study examined patterns of consummatory behavior in normal and vasopressin-deficient rats under ad lib and food-restricted conditions. Differing patterns of intake of food, water, sucrose, and saccharin were found in the two groups. During the ad lib period, the normal rats gained more weight and ate significantly more food ...

Effects of 4-week food restriction and ethanol consumption on natural killer (NK) cell activity and carcass composition were evaluated. Female, C57BL/6 mice given water (H2O) or ethanol (20% w/v, ETOH) ad libitum were placed in one of three dietary groups: unrestricted (UNR), moderately restricted (MR, 2.2 g/day), or severely restricted ...

Accumulation of glycation products (as revealed by the thiobarbituric test and hexosyllysine assay) and the pigmented products (350 nm UV absorbance and 370ex/440em nm fluorescence) in aortal and skin collagen was investigated under the conditions of different nutritional regimes. Four groups of animals were tested: (1) ad libitum fed controls, ...

1. The interrelationship between food intake, body weight and oxygen consumption was analysed at 25 degrees C in growing rats. 3. The experiment was divided into two phases lasting four weeks each. During the first phase the animals were subjected to energy restriction and during the second phase they were ...

In the first experiment, the effects of food availability on growth and reproduction were assessed by placing male musk shrews on 3 different feeding schedules, i.e. fed ad libitum, fed 50% of the amount eaten by the ad-libitum controls or fed 25% of the amount eaten by the ad-libitum controls. ...

Foods rich in nucleic acids, which elevate serum uric acid levels, are restricted in the diets of hyperuricemic individuals. This restriction has been based on the amount of total dietary nucleic acids or all purines, assuming no differences in uricogenic effects of individual purines (adenine, guanine, hypoxanthine, and xanthine). However, ...

The effect of feeding schedules on the daily rhythm in spontaneous yawning activity was studied in high yawning (HY) Sprague-Dawley rats. If the animals are fed ad libitum and changed from a standard 12-12 light-dark (LD) illumination regime to constant light (LL), the normal predark circadian peak in yawning disappears, ...

The effect of severe food restriction on the histopathology of the gut following infection with epizootic diarrhoea of infant mice (EDIM) rotavirus was studied in mice. Over a period of 12 weeks, weanling mice were fed either 70 or 50% of the diet eaten by a control group on the ...

When caged in groups of three and fed ad libitum, dominant male mice survived longer than subordinate group members which again lived longer than males caged in groups of nine, among whom no rank order was established. In groups of nine the social structure was not affected when the food ...

Reducing dietary intake has been shown to be the most effective means for modulating aging processes in laboratory rodents. Dietary restriction has also been shown to be a modulator of membrane lipid peroxidation and cytosolic antioxidant status. In the present study, anti-radical action of dietary restriction was investigated further by ...

Lead (Pb) depresses growth in infants and young children. Our earlier studies using a weanling rat model of Pb exposure suggest that this Pb effect is due to depression of appetite. In the present study we examined whether this depression of appetite is consistent with a down-regulation of the appetite ...

Corpulent rats of the JCR:LA-corpulent strain spontaneously develop atherosclerotic lesions, occlusive thrombi and myocardial lesions. In addition to exhibiting a VLDL hyperlipidemia they are insulin resistant. Young male corpulent rats have significantly impaired rates of clearance of plasma glucose on an intravenous glucose tolerance test in comparison to lean rats ...

A study was conducted among mothers in a suburban community in Lagos to ascertain child feeding patterns during episodes of diarrhoea. Two hundred women with children of 6 to 36 months were selected randomly from 672 who were participating in a diarrhoea surveillance study. The vast majority restricted the consumption ...

A serodiagnostic test based on antigen 60 has been used to analyse the presence of IgG antibodies specific for mycobacteria, in the serum of the employees of a food supermarket. More than fourteen percent of the employees were seropositive, compared to 1.5% in a health adult population. The seropositives were ...

The mechanisms involved in the recovery of body fat and liver metabolism after food restriction and refeeding are not understood. This study's aim was to determine the need for hepatic neural input for the compensatory changes in food intake, body composition and hepatic lipogenic enzymes seen upon realimentation after energy ...

These studies focused on the phenomenon of "catch-up" pubertal development. Circulating levels of several hormones were characterized in 8-wk-old female rats whose growth and reproductive development had been blocked before puberty by restricting their food intake. Some of these females were fed ad libitum for 24 h to initiate rapid ...

Oxytocin is a hypothalamic neuropeptide with both centrally and peripherally directed pathways. Data from experimental animals indicate that oxytocin impairs consolidation of aversively conditioned behaviors and is released after feeding or experimental gastric distension. The authors report that the mean CSF oxytocin level of five underweight women with restricting anorexia, ...

Dietary restriction without malnutrition prolongs life and has a beneficial effect on age-related diseases and metabolic derangements. To test the effect of food restriction on ethane production rate, ethane exhalation was measured in rats with partial food restriction. Ethane production rate in room air in rats fed 60% of food ...

Maternal beliefs regarding diet during common childhood illnesses--diarrhea, fever, measles, cough and marasmus were determined in 143 rural mothers by using the interview technique. Some foods were preferred while others were restricted during episode of each illness, depending upon their 'hot' and 'cold', 'light' and 'heavy' and other characteristics, as ...

Some laboratory studies have suggested that whereas food restriction in animals leads to response alternation (behavioural flexibility), water restriction induces perseverative, stereotyped responding. Hooded rats, restricted to 1 hour per day access to either food or water, were tested on a radial-arm maze (using a procedure that eliminates algorithmic response ...

Long-term food restriction exerts an anti-aging action in rodents. The mechanism underlying its modulation of aging processes is unknown but changes in endocrine systems have been postulated as couplers of food restriction to aging. The effects of long-term food restriction on the serum concentrations of thyroid hormones were examined in ...

In addition to thyroid hormone, carbohydrate oxidation appears to influence the relative distribution of rodent cardiac isomyosin (V1, V2, V3), especially in diabetic, thyroid-deficient, and food-restricted animals. To determine whether metabolic variations within the myocardium itself contribute to cardiac isomyosin distribution, food-restricted rats (predominantly V3) were treated with oxfenicine, a ...

We measured the clearance rate of plasma kallikrein by the liver in three groups of rats: one recently weaned, and two seven weeks old (control and food-restricted groups). The clearance rates were similar in the three groups when expressed as units/g liver. The livers of the recently weaned and food-restricted ...

Restricting the food intake of rodents extends the median length of life and the maximum life-span. It also retards most age-associated physiologic change and age-associated diseases. Our research indicates that the ability to retard disease processes is not the major reason for the extension of life-span or for the retardation ...

The major difficulty in defining the mechanisms for the action of food restriction relates to its diversity and lack of specificity. In searching for the common factor(s) and commonality involved in such diversified effects, a cellular homeostasis mechanism is proposed. A study initiated in our laboratory strongly indicates that the ...

Food consumption, development of body weight, lifespan and incidence of spontaneous diseases and tumours were investigated in 3 groups of 96 male Han:SPRD rats each maintained in a longevity study from weaning up to their natural death. All rats were fed a commercial cereal-based diet. One group received food ad ...

Research on the metabolic control of feeding has been almost exclusively restricted to the study of laboratory rats. This poses no problem if all animals respond to metabolic challenges similarly; however, they do not. Unlike rats, Syrian, Turkish, and to a lesser degree, Siberian hamsters do not increase their food ...

A variety of physiological and behavioral parameters which relate to metabolism were continuously monitored in 18 month old female Fischer 344 rats which were maintained on either ad libitum or reduced calorie diets. Caloric restriction (CR) stimulated average motor activity per day, the duration of each feeding episode, food consumed ...

1. Male and female Wistar-strain rats were studied under either ad libitum or 23-hour food restriction conditions both with and without access to a running wheel. 2. Daily measures were taken of body weight, food consumption and wheel revolutions. 3. It was observed that food restriction was associated with decreased ...

The aim of this study is to provide clearer guidelines for rational, safe, and practical dietary restriction for use with monoamine oxidase inhibitors. Tyramine levels were assayed in over 100 of the controversial foods that have been associated with hypertensive reactions or reported to contain high levels of tyramine. Only ...

Metabolic rate (MR) is widely regarded as an important component of aging processes. Decreased MR has been suggested as a possible mechanism of the life-prolonging action of food restriction in rodents and recent reports show lowered plasma levels of tri-iodothyronine (T3), a regulator of MR, in food restricted rodents. In ...

Food restriction or decreasing the ratio of [Na+, K+] to [Ca++, Mg++] in the diet of female rats before conception favoured the production of female offspring. Seven days of food deprivation decreased uterine fluid GPC diesterase activity in female rats, whereas long-term food restriction (21 days), rather than decreasing the ...

Female hooded rats were ovariectomized and implanted with a single testosterone-filled Silastic tube or an empty tube. The tube size was one which allowed a release of testosterone at the high end of the mean normal serum testosterone concentration for intact females. Following a 7-day recovery period, all rats were ...

It is widely held that restriction of food intake leads to a decrease in metabolic rate, and this effect has been implicated as the mechanism by which food restriction retards aging in laboratory rodents. Data on which this belief is based were obtained mostly from studies of basal metabolic rate ...

To assess which membrane properties are modulated by the action of food restriction, characteristics of liver membrane structures of ad libitum-fed and food restricted Fischer 344 rats were analyzed over a wide age range. The results show that the yields of mitochondrial and microsomal membranes decreased in ad libitum-fed rats, ...

Chronic nephropathy involving glomerular sclerosis markedly progresses in severity with age in male Fischer 344 rats fed ad libitum. Restricting food intake by 40% almost totally prevents progression of these lesions. Restricting food intake by 40% without restricting protein intake is also highly effective although somewhat less so than food ...

Urinary excretions of creatinine (CR) and 3-methylhistidine (3-MeHis), and skeletal muscle mass (SKM) were measured in rats (male, Wistar, weighing about 290 g) fed a 20% casein diet ad libitum, rats restricted to 70% of the food intake of the ad libitum group, and rats deprived of food for 20 ...

Primiparous, post-partum mated BALB/c bom inbred mice were allowed to raise litters of 6 young until Day 22 of lactation: 11 of 25 females were restricted to 60% of food consumption of ad-libitum fed dams after stud male removal at Day 2 of lactation. Since weight gain of restricted females ...

The susceptibility of experimental rats to Aflatoxin B1, a well known hepatocarcinogen, during chronic food restriction was studied, using a few putative preneoplastic biochemical markers. Gamma-Glutamyl transpeptidase was the most sensitive among the various enzymes studied, at the dose of 10 micrograms/day/100 gm body weight of Aflatoxin B1 fed over ...

Calorie restriction results in an increased lifespan and reduced fecundity of rodents. In a natural environment the availability of food will vary greatly. It is suggested that Darwinian fitness will be increased if animals cease breeding during periods of food deprivation and invest saved resources in maintenance of the adult ...

The pattern of activity obtained in rats on a regimen of one hour access to food and water was compared to the activity pattern seen when immobilization stress was added to the same regimen. Food and water were provided at the same time of the day. Immobilization stress decreased the ...

The JCR:LA-corpulent rat is a congenic strain that, if homozygous for the cp gene, is obese with a very low-density lipoprotein hyperlipidemia and is insulin resistant. The male corpulent rats develop atherosclerotic lesions of the major arteries and myocardial lesions. Corpulent and lean male rats were induced through mild food ...

Glucose has been proposed as a mediator of aging processes by means of glycation reactions resulting in advanced glycosylation end-products, thereby altering protein and DNA function. Testing this provocative concept has a high priority in gerontologic research. In this study, food restriction of rats--a procedure which markedly retards aging processes--was ...

A Gompertz age-specific mortality rate model characterizing actuarial effects of food restriction in rats was developed based on mortality data from the study of Yu et al. (J. Gerontol. 40: 657-670, 1985). Results indicated that in the presence of adequate nutrition, food restriction reduces the aging rate parameter in a ...

The present work compares the effects of post-weaning crowding and those of food restriction on growth, body weight gain and the levels of several hormones, in male Sprague-Dawley rats. Crowding resulted in reduced food intake and diminished body weight gain. Rats daily receiving the same amount of food as that ...

Recent data referring to the influence of a restricted diet on the incidence of radiation-induced tumors and leukemia in rats and mice are reviewed. The incidence of tumors developing in rats exposed to total-body gamma irradiation was reduced from 93% to 35% in female rats and from 59% to 7% ...