Biomedical subjects

R Savard

Publications and source records attributed to R Savard.

At least 19 recordsLinked to original sources

PubMed2005

New Lactobacillus acidophilus isolates reduce the release of leptin by murine adipocytes leading to lower interferon-gamma production.

Leptin produced by adipocytes increases Th1-dependent immunostimulation and autoimmune diseases. Lactobacilli are known to promote or suppress Th1 responses according to the isolates. We have investigated whether the sensitivity of Suriss Jim Lambert (SJL) mice to Th1-dependent immune diseases, when compared with C57BL/6 mice, may be modulated by selected lactobacilli able to decrease leptin release by adipocytes. White adipocytes were isolated from both C57BL/6 and SJL mice and incubated with bacterial extracts from new CBA4P and TPA3P isolates of Lactobacillus acidophilus and L. rhamnosus 9595 (LR), or with conditioned media (CM) from lactobacillus-treated macrophages. Immunomodulation induced by supernatants of treated adipocytes was determined by metabolic activity of syngenic splenic lymphocytes. Leptin produced by adipocytes, tumour necrosis factor (TNF)-alpha and interleukin (IL)-1beta by macrophages, and IFN-gamma and IL-4 by lymphocytes were quantified by enzyme-linked immunosorbent assay (ELISA) tests. Results revealed that supernatants from CBA4P- and LR-treated adipocytes decreased the metabolic activity of lymphocytes from SJL mice, whereas adipocytes incubated with CM from CBA4P-treated macrophages showed no stimulation of lymphocytes. Such effects correlated with leptin levels. Lower levels of leptin were produced by adipocytes from SJL mice in the presence of CBA4P and LR extracts. Lymphocytes from SJL mice produced low levels of IFN-gamma when incubated with supernatants from CBA4P-treated cells. Such immunosuppressive effects were dependent on levels of TNF-alpha and IL-1beta produced by lactobacillus-treated macrophages. Taken together, these results suggest that the CBA4P isolate reduces levels of leptin in SJL mice, leading to lower IFN-gamma production. Therefore, the CBA4P isolate of L. acidophilus is a promising new probiotic strain for the control of Th1 inflammatory diseases.

Adipocytes↗

PubMed1999

Impact of a cholesterol enriched diet on maternal and fetal plasma lipids and fetal deposition in pregnant rabbits.

Pregnancy is associated with a hypercholesterolemic and a hyperlipidemic state. The totality of the essential fatty acids and 50% of the lipids needed by the fetus are transferred by the placenta from the maternal circulation. The hypothesis of this study is that an augmentation of the maternal plasmatic cholesterol is modifying the fetal lipids accumulation and development during rabbit pregnancy. To demonstrate the impact of a cholesterol enriched diet on plasma lipids during rabbit's pregnancy and on their fetus, we have established two groups: control and hypercholesterolemic rabbits (fed with a 0.2% cholesterol diet). Blood samples were collected before mating and at each trimester of pregnancy for analysis of lipid fractions and their lipoproteins. Plasma analysis shows that starting the 10th day of pregnancy the concentration of total-cholesterol and lipoproteins decreases for both groups. We have demonstrated that for the hypercholesterolemic group, concentrations of total-cholesterol (631%) and lipoproteins are significantly higher at the end of pregnancy than those for the control group. For both groups, after 20 days of pregnancy, triglycerides metabolism was biphasic showing a significant increase followed by a diminution in their concentration. In both groups, free fatty acids increases significantly at the end of the pregnancy (537.5% for the control group and 462.5% for the hypercholesterolemic group). Furthermore, the offsprings of hypercholesterolemic dams manifest a lower birth weight (15.5%) than those of control group. Our results demonstrate that a cholesterol enriched diet modifies greatly the fetal development and lipid metabolism during rabbit's pregnancy. These modifications could be useful for the understanding of the interaction between diet and fetal development in rabbit and probably during human pregnancy.

Animals↗

PubMed1999

Seasonal and diel transitions in physiology and behavior in the migratory dark-eyed junco.

Body mass, fat stores, activities of lipogenic and lipolytic enzymes, and plasma corticosterone were measured throughout seasonal and diel transitions from fall through spring encompassing the non-migratory stages of early and mid winter, the prealternate molt, and the spring migratory stage in captive dark-eyed juncos to determine the physiological mechanisms underlying adaptations for migration. On a seasonal basis, lipid enzymes and corticosterone varied little throughout the stages even though the birds underwent dramatic alterations in mass, fat deposition, behavior, and activation of the reproductive axis. By contrast, diel changes were found in lipogenesis, lipolysis, muscle lipoprotein lipase, and plasma corticosterone when comparing birds in the two phases of spring migration--active flight and resting, as during times of stopover. In these two phases of migration, coordination of the lipogenic and lipolytic systems appear to maximize storage of fatty acids during rest and delivery/utilization during flight. Diel patterns of corticosterone revealed fairly consistent peaks during the night time (23:00) throughout the nonmigratory period. The profile of this pattern altered during the migratory period with variation between the flight and resting phases. In sum, the results from these captive studies offer a new approach for studying the regulation of migratory physiology in free-living birds.

Adipose Tissue↗

PubMed1998

The lack of bimodality in the effects of endogenous and exogenous prostaglandins on fat cell lipolysis in rats.

The aim of this study was to investigate and clarify the role of prostaglandins (PG) on fat cell lipolysis in female rats. Incubations with adenosine deaminase (ADA) were used for the deamination of endogenous adenosine and increased basal (155%) and isoproterenol (10(-9) M) (348%) stimulation of glycerol release from adipocytes. Indomethacin and aspirin increased the effects of ADA while indomethacin further increased isoproterenol (with ADA) stimulation of lipolysis (p < or = 0.05). Exogenous PGE2 and PGI2 inhibited the isoproterenol and ADA stimulation of fat cell lipolysis (p < or = 0.05). The expected stimulatory effect of high concentrations of PGE2 and of low concentrations of PGI2 was not observed in the presence of ADA. Dose-response curves revealed that the inhibitory effects of PGs were reached at lower concentrations for PGE2 than for PGI2 (p < or = 0.05). In conclusion, this study showed that endogenous and exogenous PGs of adipose tissue only express an antilipolytic action on fat cell lipolysis. This effect appears to be highly significant when the beta-adrenergic pathway is stimulated. Our results also stress the need to control the antilipolytic effects of adenosine to study the regulation of fat cell lipolysis by PGs.

Adenosine↗

PubMed1997

Solution structure of neuropeptide tyrosine 13-36, a Y2 receptor agonist, as determined by NMR.

The three-dimensional structure of neuropeptide tyrosine (NPY) 13-36, a specific Y2 receptor agonist, has been investigated by two-dimensional 1H-NMR spectroscopy in solution. Analysis of the double-quantum-filtered correlation spectroscopy (DQFCOSY), total correlation spectroscopy (TOCSY) and nuclear Overhauser enhancement spectroscopy (NOESY) spectra provided a complete assignment of the proton signals. The interproton connectivities observed in the NOESY spectra comprised 166 intraresidue and 95 interresidue distance ranges which were used as constraints for molecular modeling by distance geometry, simulated annealing and energy minimization. The optimal structures are characterized by a helical C-terminal fragment Leu30-Tyr36 and a wide loop from Leu17 to Ser22. The structure of NPY 13-36 is analogous to the structure of NPY under the same solvent conditions. Comparison with other reported Y2 agonists suggests that the helical Leu30-Tyr36 fragment is the most critical for activity.

Animals↗

PubMed1997

Tissue-specific regulation of fat cell lipolysis by NPY in 6-OHDA-treated rats.

The effects of neuropeptide Y (NPY), peptide YY (PYY), [Leu31, Pro34]NPY, and NPY (13-36) on adipocyte lipolysis have been studied in subcutaneous (inguinal) and visceral (parametrial) rat adipose tissues. A 48-h fasting period and chemical sympathectomy were used to evaluate the regulation of Y1 and Y2 pathways in rat adipocytes. NPY, PYY, and [Leu31, Pro34]NPY significantly inhibited fat cell lipolysis by about 25% in both tissues (p < or = 0.05). This inhibition was achieved mainly through the Y1 pathway. No significant response to NPY (13-36) was observed, suggesting a lack of involvement of the Y2 pathway in the antilipolytic effect of NPY and PYY. The 48-h fasting period led to the loss of the Y1 inhibitory effect previously observed in control rats. On the other hand, the chemical sympathectomy induced a 35% increase of fat cell lipolysis (p < or = 0.05). The latter involved the Y2 pathway as stimulated by NPY (13-36), and was observed in the parametrial tissue exclusively. These results suggest that: a) rat Y receptors reported to exhibit Gi responses can also express Gs-like responses, and b) visceral and subcutaneous adipose tissues exhibit specific regulation of fat cell lipolysis.

Adipocytes↗

PubMed1995

The effects of a selective alpha-1 adrenergic blockade on the activity of adipose tissue lipoprotein lipase in female hamsters.

Lipoprotein lipase, is an enzyme responsible for the hydrolysis of triacylglycerols at the surface of endothelial cells. Its regulation is not completely elucidated and seems, among other things, under the influence of the sympathetic nervous system. The adrenergic regulation of lipoprotein lipase activity is complex and the alpha 1 adrenergic pathway appears involved in this regulation. In the present study, adipose tissues of female hamsters are investigated following a single injection of doxazosin and phenylephrine and are compared to controls for the activity of lipoprotein lipase. After an acute treatment with a selective alpha 1 antagonist (doxazosin), lipoprotein lipase activity was decreased in the parametrial white adipose tissue and increased in brown adipose tissue (p < or = 0.05). Moreover, a treatment with phenylephrine, an alpha 1 adrenergic agonist, increased the activity of lipoprotein lipase, in the parametrial fat pad only. On the other hand, the activity of lipoprotein lipase in heart and in skeletal muscle was not modified by an alpha 1 stimulation or blockade. In this study, calcium and norepinephrine did not appear involved in the regulation of lipoprotein lipase activity. On the contrary, the increase of plasma glycerol after an acute treatment with doxazosin suggests that the lipolytic activity of white adipose tissue could be involved in the decrease of lipoprotein lipase activity in the parametrial white adipose tissue.

Adipose Tissue↗

PubMed1995

Site-specific effects of sympathectomy on the adrenergic control of lipolysis in hamster fat cells.

Regional variations in the response of adipose tissue to lipolytic stimuli have been suggested to be involved in the development of visceral adiposity-related morbidity and mortality. Moreover, studies in humans and in laboratory rodents such as hamsters have shown that the response of adipocytes to catecholamines depends on their anatomical origin. The aim of the present study was to investigate the relative involvement of the adrenal medulla and of the sympathetic nervous system on regional differences in the adrenergic control of lipolysis in isolated adipocytes from inguinal and epididymal adipose tissues. For this purpose, we carried out adrenal demedullation or chemical sympathectomy in hamsters. The results confirmed that epididymal adipocytes were significantly more responsive to to a beta-adrenergic stimulation than inguinal adipocytes (p < or = 0.05). This site specificity could originate at a step distal to receptors since tissues exhibited a similar number of binding sites for [125I]cyanopindolol. No significant regional differences were observed in the alpha2-adrenergic antilipolytic response, with the exception of the clonidine EC50. A 14-day sympathectomy significantly increased the beta-adrenergic lipolytic response only in inguinal adipocytes (p < or = 0.05), and increased the alpha2-adrenergic response only in epididymal adipocytes (p < or = 0.05). On the other hand, adrenal demedullation had no effect on both adrenergic pathways. These results suggest that the sympathetic tone of adipose tissues could be involved in the alpha2- and beta-adrenergic site-specific response in hamster fat cells. The 33% increase of the beta-response in inguinal fat cells and the 38% increase of the alpha2-response in epididymal fat cells also suggest that the sympathetic pathway favors the lipolytic activation of the epididymal adipose tissue.

Adipocytes↗

PubMed1994

Linoleic acid transport by human placental syncytiotrophoblast membranes.

The placenta syncytiotrophoblast is the site of exchange of nutrients, lipids and minerals between the mother and the fetus. In order to characterize the transport of fatty acids by the placenta, we purified bipolar syncytiotrophoblast brush border and basal plasma membranes from human placenta. These purified brush border and basal plasma membranes enriched 3-fold and 22-fold, respectively, in sodium/potassium-ATPase and 27-fold and 6-fold in alkaline phosphatase activity, compared with the placental homogenates. Fatty acid transport was performed at different fatty acid/albumin ratios to evaluate the optimal uptake conditions. The maximal transport efficiency, for linoleic acid bound to albumin by sonication, was obtained with a 6:1 fatty acid/albumin ratio in brush border and basal plasma membranes. The linoleic acid transport observed with brush border membranes followed Michaelis-Menten kinetics, with a Michaelis constant of 7.89 +/- 0.01 microM and a maximal incorporation rate of 30.80 +/- 6.39 pmol.mg-1.min-1. Linoleic acid transport was very low in basal plasma membranes and we obtained a Michaelis constant of 0.95 +/- 0.01 microM and a maximal incorporation rate of 1.62 +/- 5.06 pmol.mg-1.min-1. In order to show that linoleic acid accumulated within brush border and plasma membrane vesicles, and to eliminate the possibility of a non-specific binding of fatty acid to these membranes, we demonstrated by an osmolarity experiment, the decrease of the linoleic acid transport in brush border and basal plasma membranes obtained in the presence of 455 microM essential fatty acid at 23 degrees C for 180 min. The results presented in this study suggest that linoleic acid is transported significantly by syncytiotrophoblast brush border membranes and basal plasma membranes. Thus, it may represent a unidirectional transport from mother to fetus through the brush border membranes facing the mother, followed by transport at a slower rate through basal plasma membranes facing the fetus.

Albumins↗

PubMed1994

Calcitonin receptor in human placental syncytiotrophoblast brush border and basal plasma membranes.

The physiology of calcium transport through the placenta has not been studied thoroughly. In particular, the effect of calcaemic hormones on this process has never been reported. In this paper we questioned if calcitonin, a hypocalcaemic hormone, is also implicated in the regulation of calcium transport by one of the placental syncytiotrophoblast bipolar membranes. In order to investigate the implication of calcitonin on calcium transport, we first studied whether this hormone binds to any of these bipolar membranes, i.e. purified syncytiotrophoblast brush border (facing the mother) and basal plasma membranes (facing the fetus). The initiation of binding of human [125I]calcitonin to the two types of membranes was rapid and reached a steady state after 10 min of incubation at 37 degrees C. The number of binding sites and the affinity of these receptors for the hormone were studied for each type of membrane, with concentrations of [125I]calcitonin varying from 0.01 to 1.8 nM. Scatchard analysis revealed a single affinity binding site for human calcitonin with Kds of 0.83 +/- 0.09 nM and 0.67 +/- 0.26 nM for brush border and basal plasma membranes respectively. The maximal number of receptors was significantly different (p < 0.001) in the two membranes: Bmax of 66.64 +/- 9.15 fmol/mg protein for brush border membranes and 19.66 +/- 2.80 fmol/mg protein for basal plasma membranes. Competitive displacement of [125I]calcitonin with other ligands showed the following potencies between human calcitonin > salmon calcitonin > calcitonin gene-related peptides and segments analogues but no competition with some human calcitonin gene-related peptides fragments.(ABSTRACT TRUNCATED AT 250 WORDS)

Binding, Competitive↗

PubMed1994

Modulation of exercise-induced immunosuppression by dietary polyunsaturated fatty acids in mice.

The possible interaction between intense exercise, known to suppress the immune response, and nutritive factors, such as polyunsaturated fatty acids (PUFA), was examined in inbred female C57Bl/6 mice. The animals received for 8 wk either a natural ingredient diet or a diet supplemented with 10 g/100 g linseed oil containing over 50% of 18:3 (n-3) alpha-linoleic acid. Other groups received PUFA containing only traces of 18:3 (n-3) fatty acid; beef tallow, containing mostly 18:1 (n-9) saturated fat, safflower oil, an 18:2 (n-6) PUFA, and fish oil, containing longer chain (n-3) PUFA. Each dietary group was divided into two subgroups: sedentary diet controls and exercised animals. Exercise consisted of continuous swimming at high intensity until exhaustion. It was shown in three separate experiments that (1) the primary humoral response to sheep red blood cells, determined by the plaque-forming cell (PFC) assay, was affected by PUFA diet in sedentary animals in the order beef tallow > control diet > safflower oil > fish oil > linseed oil, and (2) the PFC response was suppressed by the exhaustive exercise, as compared to sedentary controls, except for animals fed 18:3 (n-3) linseed oil, where the normal response was noted. Phagocytosis of fluorescent microspheres by peritoneal macrophages, determined by flow cytometry, was significantly lower in exercised animals receiving the linseed oil diet, whereas other diets either increased or did not significantly change the macrophage phagocytic activity, compared to the sedentary diet controls. Spleen lymphocyte subsets were unchanged in exercised animals except for a marked shift from the lymphoid peak toward the erythroid peak. Generally, our data showed a marked immunomodulatory effect of 18-3 (n-3) alpha-linoleic acid on the exhaustive exercise-related immunosuppression, as compared to the effects of other selected PUFA.

Animals↗

PubMed1992

Vitamin B12 among parturients and their newborns and its relationship with birthweight.

Vitamin B12 (Cobalamin) is an essential nutrient in the diet of humans, particularly during pregnancy, nevertheless very few epidemiological studies have been reported, particularly concerning variation factors. The purpose of this study is to assess the role of vitamin B12 on birthweight after taking into account potential confounders, such as obstetrical, socioeconomic, and biological factors which will be identified. This study was conducted on 188 single births occurring during a 5-month period in an obstetrical care unit in Paris. Vitamin B12 plasma levels and folate plasma levels of mothers and cords along with haematological parameters were measured. Social and obstetrical features of the mothers as well as their tobacco exposure and alcohol consumption were recorded. Cord blood vitamin B12 levels were highly correlated with maternal levels (r = 0.63, P less than 0.001) and were 2-3-fold higher. Three variation factors of vitamin B12 were identified: maternal age, ethnicity and tobacco exposure. Negative correlations between birthweight and vitamin B12 levels were observed only among the smoker group (r mothers = -0.46, P less than 0.05 and r cords = -0.42, P less than 0.05). After adjustment for ethnicity and parity, birthweight remained negatively linked to vitamin B12 in smokers. This relationship could suggest that the availability of vitamin B12 for fetal development depends on certain biological factors present only in mothers who smoked. We hypothesized this relationship could be explained, in part, by lipid metabolism, particular to smokers.

Adult↗

PubMed1991

A north-temperate migratory bird: a model for the fate of lipids during exercise of long duration.

Changes in deposition and the utilization of lipids during one night of migratory activity (nocturnal physical activity) were investigated in dark-eyed Juncos (Junco hyemalis) held in large outdoor aviaries. During vernal migration (May), captive Juncos were sampled at the beginning and conclusion of one night of nocturnal restlessness. Comparisons of variables were drawn with control samples collected from birds in March. Measurements included body weight, fat stored in subcutaneous depots (adiposity), adipose and muscle lipoprotein lipase activity, and fat cell lipolysis. During the migratory period, body weight and adiposity were increased over levels measured in the March birds (p less than 0.01). On the other hand, neither body weight nor adiposity were significantly altered as a result of nocturnal physical activity and no significant changes were observed in adipose lipoprotein lipase activity. Fat cell lipolysis was lower at the beginning than at the end of nocturnal physical activity while, the opposite was observed for muscle lipoprotein lipase activity (p less than 0.05). These results suggest that the amount of work of one night of nocturnal physical activity modifies both muscle lipoprotein lipase activity and fat cell lipolysis in an interrelated fashion. This phenomenon could act to direct a steady supply of fatty acids to the site of energy utilization, i.e., flight muscles.

Adipose Tissue↗

PubMed1990

Genetic effects in the response of adipose tissue lipoprotein lipase activity to prolonged exercise. A twin study.

Our laboratory has reported large inter-individual differences in the metabolic response of adipose tissue to prolonged exercise in humans. The present study investigated the contribution of heredity in the metabolic changes of adipose tissue to prolonged exercise in 11 monozygotic and 10 dizygotic pairs of male twins, 18 to 27 years of age, studied immediately before and after a 90 min bout of exercise. The sum of 7 skinfold thicknesses and percent of fat from underwater weighing were used as body fat indicators (BFI). Subcutaneous adipose tissue was excised and fat cell weight (FCW) determined. The activity of adipose tissue lipoprotein lipase (LPL) released with heparin was also measured. BFI and FCW were identical in both types of twins. As previously reported, LPL activity was increased by exercise (P less than 0.01) in both type of twins. The changes observed for LPL activity were more similar in monozygotic twins than in dizygotic twins resulting in a significant level of inheritance (P less than 0.05). A genetic component for LPL activity supports the hypothesis that adipose tissue LPL could be genetically determined not only in its basal activity but also in response to stresses such as exercise.

Adipose Tissue↗

PubMed1988

Site specific effects of acute exercise on muscle and adipose tissue metabolism in sedentary female rats.

The effects of endurance exercise on muscle, and adipose tissue metabolism were investigated. Female lean Zucker rats swam for two hours at high intensity. Three groups were examined: pre-exercise control (C), exercised (E) and 24 hours post-exercise (E-24). Exercise increased fat cell lipolysis in the inguinal depot (p less than 0.05) while no effect was detected in the parametrial depot. In contrast, parametrial pad lipoprotein lipase (LPL) activity decreased after exercise with 24 hours post-exercise values being reduced below E and C rats (p less than 0.05). Gastrocnemius LPL activity remained unchanged during exercise while heart LPL increased, E having higher values than C and E-24 (p less than 0.05). Gastrocnemius, but not heart, citrate synthase activity increased with exercise, with E-24 values increased compared to E and C (p less than 0.05). These results demonstrate that adipose tissue's response to exercise is site specific, and suggests a distinct physiological role for different adipose depots. Muscle LPL and citrate synthase activities were modified differently for gastrocnemius and heart, confirming the distinct metabolic response to exercise of these two muscles.

Adipose Tissue↗

PubMed1988

Site-specific adipose tissue LPL responses to endurance training in female lean Zucker rats.

The effects of endurance exercise training on adipose tissue have been investigated in female lean Zucker rats. Adult trained rats (TR) were followed throughout a swimming program of 5 wk and were compared with a littermate control sedentary group (SED). Data were collected on days 0, 14, 24, and 36 of the training program. Body weight gain and cumulative food intake were significantly lower in TR than in SED (P less than 0.05). Gastrocnemius citrate synthase activity was increased in TR by day 14 of training (P less than 0.05) and was followed by a second significant increase between days 24 and 36 (P less than 0.05). Although inguinal (ING), parametrial (PAR), and retroperitoneal (RP) cell sizes were decreased by the swimming program (P less than 0.05), adipose tissue lipoprotein lipase (LPL) activity was suppressed (P less than 0.05) by training during the first 24 days in PAR and RP depots only. Thereafter, PAR and RP LPL activities increased in TR animals (P less than 0.05) to reach values similar to SED at the end of the study. These results further establish the regionally specific response of adipose tissue metabolism to endurance training. They also suggest that, when fat cell triacylglycerol depletion reaches a smaller level, LPL activity could be involved in the process of stabilizing fat cell size.

Adipose Tissue↗

PubMed1987

Acute effects of endurance exercise on human adipose tissue metabolism.

In order to study the acute effects of exercise on adipose tissue metabolism, 27 sedentary male subjects, 18 to 27 years of age, performed a prolonged aerobic exercise test. Biopsies of adipose tissue were obtained from the suprailiac fat depot before and immediately after a 90-minute period of exercise on ergocycle at an average intensity of 88% of maximal heart rate. Fat cells, isolated by collagenase digestion, were measured for their glucose conversion into triglycerides and for lipolytic activity. Adipose tissue lipoprotein lipase activity released by heparin was also determined. Mean basal and insulin-stimulated glucose conversion into triglycerides decreased significantly with exercise (P less than .05) while adipose tissue lipoprotein lipase activity increased (P less than .01). Fat cell lipolysis increased during exercise only for its epinephrine-stimulated values (P less than .05). The total amount of work performed during the test was correlated only with changes in lipoprotein lipase activity (r = .42, P less than .05). Finally, the changes induced by exercise in lipoprotein lipase activity (r = .37, P less than .05) and insulin-stimulated glucose conversion into triglycerides (r = .61, P less than .01) were positively correlated with fat cell weight. These results indicate that adipose tissue metabolic activities are selectively influenced by endurance exercise. They also suggest that these metabolic changes are not closely coupled with the amount of work performed in a prolonged exercise bout.

Adipose Tissue↗

PubMed1986

Effects of exercise training on regional adipose tissue metabolism in pregnant rats.

To investigate the effects of intense exercise training on maternal adiposity and fetal development, normal lean Zucker (Fa/Fa) rats were divided into three groups: control nonpregnant (CNP), control pregnant (CP), and exercise-trained pregnant (TRP). Trained rats swam three continuous hours per day, 6 days/wk, throughout pregnancy. Food efficiency increased with pregnancy, the highest values being observed during the last trimester of the gestation period. On day 21, pup number, weight, and body composition were similar for CP and TRP. By day 21 of gestation, in both TRP and CP rats, inguinal adipose tissue weight, cell size, and lipoprotein lipase (LPL) activity increased; although TRP values were smaller (P less than 0.05). In CP rats, parametrial and retroperitoneal adipose tissue weights, cell size, and LPL activities increased throughout pregnancy, whereas TRP values were similar to CNP (P less than 0.05). Parametrial fat cell lipolysis showed, however, no effect of training. These results indicate that the extensive energy expenditure occurring during endurance training selectively reduced the dams' adiposity in a regionally specific fashion without any apparent alteration in pup development. The increased substrate utilization required by training during pregnancy did not, however, modify fat cell lipolysis but rather prevented lipid filling through suppression of LPL activity of some depots.

Adipose Tissue↗