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Intestinal and placental calcium-binding proteins in vitamin D-deprived or -supplemented rats.
1978
Marche P. | Delorme A. | Cuisinier Gleizes P.
Unexpected regulation of hypothalamic neuropeptide Y by food deprivation and refeeding in the Zucker rat.
1992
Beck B. | Burlet A. | Nicolas J.P. | Burlet C.
Neuropeptide Y strongly stimulates food intake when it is injected in the hypothalamic paraventricular (PVN) arid ventromedian (VMN) nuclei. In Sprague-Dawley (SD) rats, NPY synthesis in the arcuate nucleus (ARC) is increased by food deprivation and is normalized by refeeding. We have previously shown that the obese hyperphagic Zucker rat is characterized by higher NPY concentrations in this nucleus. NPY might therefore play an important role in the development of hyperphagia. The aim of the present study was to determine if the regulation by the feeding state works in the obese Zucker rat. For this purpose, 10 weeks-old male lean (n=30) and obese (n=30) Zucker rats were either fed ad libitum, either food-deprived (FD) for 48 hours or food-deprived for 48 h and refed (RF) for 6 hours. NPY was measured in several microdissected brain areas involved in the regulation of feeding behavior. NPY concentrations in the ARC was about 50% greater in obese rats than in lean rats (p < 0.02) whatever the feeding state. In the VMN, NPY concentrations were higher in the lean FD rats than in the obese FD rat (p < 0.001). Food deprivation or refeeding did riot modify NPY in the ARC, in the VMN or in the dorsomedian nucleus whatever the genotype considered. On the other hand, food deprivation induced a significant decrease in NPY concentrations in the PVN of lean rats. This decrease was localized in the parvocellular part of this nucleus (43.0 +/-1.9 (FD) vs 54.2 +/- 2.1 (Ad lib) ng/mg protein; p < 0.005). Ad lib levels were restored by 6 hours of refeeding. These variations were not observed in the obese rat. The regulation of NPY by the feeding state in the Zucker rat was therefore very different from that described in the SD rats. Strain or age of the animals used might explain these differences. High NPY levels and absence of regulation in obese Zucker rats could contribute to the abnormal feeding behavior of these rats.
Show more [+] Less [-]Effects of exercise on immune functions of undernourished mice.
1992
Filteau S.M. | Menzies R.A. | Kaido T.J. | O'Grdy M.P. | Gelderd J.B. | Hall N.R.S.
Regular moderate exercise may modulate the response to a stressor and thus improve immune functions in conditions commonly associated with immunodepression and elevated levels of stress hormones. For example, anorexia nervosa patients, many of whom engage in regular aerobic exercise, generally have normal immune function and viral disease resistance in spite of their severe undernutrition. To test the hypothesis that exercise can prevent undernutrition-induced immunodepression, mice were fed a nutritionally complete, semi-purified diet, either ad libitum or in restricted quantities to induce 25% loss of initial weight over 3 weeks. Half the animals from each dietary group were run on a treadmill for 30 min/day, 5 days/week. Exercise had no effect on several measures of nutritional status. Spleen weight and blastogenic response to lipopolysaccharide were significantly increased by exercise in undernourished mice. In vivo antibody response to sheep red blood cells, and in vitro splenic responses to concanavalin A and phytohemagglutinin were not significantly affected by exercise. Serum corticosterone level was increased by food restriction and significantly decreased by exercise in the undernourished mice. Within a treatment group there were no significant correlations between serum corticosterone level and any immune system measure. Hypothalamic concentration of uric acid was increased in food restriction groups and concentration of norepinephrine was increased in exercise groups. The results suggest that regular exercise may help prevent undernutrition-induced immunodepression, possibly through modulation of the stress response.
Show more [+] Less [-]A new test for measuring diapause in the pink bollworm Pectinophora gossypiella Saunders.
1992
Salama M.S. | Miller T.A. | Schouest L.P. Jr.
An ELISA test was developed to assay for the presence of a protein, pectinophorin, that is expressed only in diapausing last instar larvae of the pink bollworm, Pectinophora gossypiella Saunders. Use of the test provides a good estimation of the percent of diapause larvae in populations of pink bollworm in cotton fields in California and Arizona. All plow down dates are chosen before the majority of larvae enter diapause so as to eliminate as many overwintering survivors as possible. These dates may now be determined more precisely for any given field by use of the new ELISA procedure.
Show more [+] Less [-]Study of fatty acids in atheroma induced in rabbits by an atherogenic diet with or without silicon I.V. treatment.
1988
Loeper J. | Goy J. | Fragny M. | Troniou R. | Bedu O.
Epidermal growth factor-like proteins in breast fluid and human milk.
1988
Connolly J.M. | Rose D.P.
Hypoxia and cold: influence on cellular oxygen consuming systems in guinea pig liver.
1980
Camba E. | Montestruque S. | Alvarez J.
Differential effect of acute and chronic ethanol on dopamine metabolism in frontal cortex, caudate nucleus and substantia nigra [in rats].
1980
Fadda F. | Argiolas A. | Melis M.R. | Serra G. | Gessa G.L.
Membrane lipids and ethanol tolerance in the mouse. The influence of dietary fatty acid composition.
1980
John G.R. | Littleton J.M. | Jones P.A.
Clonidine increases food and protein consumption in rats.
1980
Mauron C. | Wurtman J.J. | Wurtman R.J.