Changes in total body calcium balance with exercise in the rat

1983 ◽  
Vol 55 (1) ◽  
pp. 201-204 ◽  
Author(s):  
A. D. LeBlanc ◽  
H. J. Evans ◽  
P. C. Johnson ◽  
S. Jhingran

The purpose of this study was to evaluate the effect of deconditioning on the total body calcium in rats. Two separate experiments were performed using female Sprague-Dawley rats, 187-266 days of age. Total body calcium was measured in experimental and control rats during and following several weeks of voluntary exercise. The slope from the least-squares fit of total body calcium with time was used to obtain an average calcium balance for each animal during each study period. In both groups the exercised rats had a significantly decreased calcium balance after cessation of exercise, whereas no significant change was seen in nonexercised controls. In both groups, the exercised animals gained calcium at a significantly greater rate than controls. Our findings indicate that while exercised rats may gain calcium at a faster rate compared with nonexercising controls, the rate of gain following cessation of exercise is less than the controls.

1976 ◽  
Vol 231 (4) ◽  
pp. 1090-1096 ◽  
Author(s):  
JG Kral

The lipostatic theory of regulation of adipose tissue mass was tested by a method for surgical reduction (adipectomy) of 24% of the total body fat of nonobese adult Sprague-Dawley rats, as judged from carcass analyses. The reduction persisted during an observation period of 12 wk without any evidence of altered food intake, weight gain, or compensatory hypertrophy or hyperplasia of adipose tissue compared with sham-operated controls. No changes were found in serum free fatty acids, glycerol, triglycerides, cholesterol, or insulin between adipectomized and control animals, implying an intact quantitative function of the remaining adipose tissue. It is concluded that the size of the adipocytes rather than the number is important for a presumed lipostatic regulation of adipose tissue mass in the adult male Sprague-Dawley rat.


1969 ◽  
Vol 62 (1) ◽  
pp. 11-20 ◽  
Author(s):  
Colum A. Gorman ◽  
James W. Anderson ◽  
Eunice V. Flock ◽  
Charles A. Owen ◽  
Khalil G. Wakim

ABSTRACT Thyroiditis was induced in Sprague-Dawley rats by repeated immunization with thyroid extract and Freund's adjuvant. Immunized and control animals were killed at intervals up to 6 hours after intravenous administration of 131I as iodide at 5, 8 and 10 weeks after the first injection. Radioiodinated compounds in the thyroid glands were identified chromatographically. Evidence of moderate thyroiditis was present (histologic appearance, gland weight, and protein-bound iodine-butanol-extractable iodine difference) but the rate of incorporation of radioiodide into thyroxine, the percentage of radioactivity in the gland as iodide, and the MIT/DIT ratio were not significantly different in immunized and control animals. The MIT/DIT ratio was found to vary with time after 131I administration in both immunized and control animals. These studies did not uncover a defect in organification of iodide in experimental thyroiditis similar to that described by others in humans with Hashimoto's thyroiditis.


2014 ◽  
Vol 40 (4) ◽  
pp. 421-424 ◽  
Author(s):  
Igor Bastos Polonio ◽  
Milena Marques Pagliareli Acencio ◽  
Rogério Pazetti ◽  
Francine Maria de Almeida ◽  
Bárbara Soares da Silva ◽  
...  

We assessed the effects of lodenafil on hemodynamics and inflammation in the rat model of monocrotaline-induced pulmonary hypertension (PH). Thirty male Sprague-Dawley rats were randomly divided into three groups: control; monocrotaline (experimental model); and lodenafil (experimental model followed by lodenafil treatment, p.o., 5 mg/kg daily for 28 days) Mean pulmonary artery pressure (mPAP) was obtained by right heart catheterization. We investigated right ventricular hypertrophy (RVH) and IL-1 levels in lung fragments. The number of cases of RVH was significantly higher in the monocrotaline group than in the lodenafil and control groups, as were mPAP and IL-1 levels. We conclude that lodenafil can prevent monocrotaline-induced PH, RVH, and inflammation.


2012 ◽  
Vol 27 (5) ◽  
pp. 301-305 ◽  
Author(s):  
Baohua Zhu ◽  
Chuanming Tong ◽  
Weitao Guo ◽  
Rong Pu ◽  
Guoping Zhang ◽  
...  

PURPOSE: To investigate synergistic suppression of donor liver pre-perfusion with recipient serum (RS) and cobra venom factor (CVF) treatment on hyperacute rejection (HAR) following liver xenotransplantation. METHODS: Guinea-pigs (GP, n=24) and Sprague-Dawley rats (SD, n=24) were recruited. Before transplantation, serum was collected from SD rats and used for preparation of inactivated complements. GP and SD rats were randomly assigned into four groups (n=6), respectively: RS group, CVF group, RS+CVF group and control group. Orthotopic liver xenotransplantation was performed with modified two-cuff technique. The survival time and liver function of recipients, morphological and pathological changes in rat livers were investigated. RESULTS: There was no piebald like change in the recipient livers in all experiment groups. The survival time of recipients in all experiment groups was longer than that in control group (p<0.05). Moreover, the survival time in the RS+CVF group was markedly longer than that in the RS group (p<0.01) and CVF group (p<0.05). The serum ALT level in all experiment groups were lower than that in the control group (p<0.05). Furthermore, the ALT level in the RS+CVF group was significantly lower than that in the CVF group (p<0.05) and RS group (p<0.01). The histological damages were significantly improved when compared with the control group, and the histological damages in the RS+CVF group were milder than those in the remaining groups (p<0.05) CONCLUSION: Pre-perfusion of donor liver with recipient serum and cobra venom factor treatment can exert synergistic suppressive effects on the hyperacute rejection following liver xenotransplantation.


Author(s):  
Nurarita Fadila Zesiorani ◽  
Effionora Anwar

Objective: This study aims to formulate and characterize a transfersome apple peel extract, formulate it into a gel, and compare it with a control gelmade without transfersome.Methods: Both gels were evaluated, stability tested, and penetration tested using Franz diffusion cells on the skin of female Sprague-Dawley rats. Thetransfersome preparations were formulated with different concentrations of the active substance, quercetin: 0.5% (F1); 0.7% (F2), and 1.0% (F3).Results: Based on the characterization results, F1 was selected as the optimum gel formulation because it had spherical morphology, a Dmean volume of106.44±2.70 nm, a polydispersity index of 0.078±0.01, a zeta potential of −49.96±2.05 mV, and a drug efficiency entrapment percentage of 78.78±0.46%.The cumulative amount of quercetin that was penetrated with the transfersome gel was 1514.41±26.31 μg/cm2, whereas the penetration with thecontrol gel extract was 1133.62±18.96 μg/cm2. The cumulative percentages of the penetrated gel transfersome and gel extract were 78.40±1.89%and 49.89±0.88%, respectively. The fluxes of transfersome gel and control gel extract were 52.33±0.11 μg/cm²/hrs and 40.89±0.68 μg/cm²/hrs,respectively.Conclusions: Based on these results, it can be concluded that the gel with transfersome exhibited better penetration than the gel extract alone.


1994 ◽  
Vol 56 (1-4) ◽  
pp. 93-97 ◽  
Author(s):  
J.P. Morlier ◽  
M. Morin ◽  
G. Monchaux ◽  
P. Fritsch ◽  
J.F. Pineau ◽  
...  

Abstract To study the effect on lung cancer incidence of a long exposure to low levels of radon, 500 male 3-month-old Sprague-Dawley rats, were exposed to a cumulative dose of 25 WLM of radon and its daughters, 6 hours a day, 5 days a week, during 18 months. Exposure conditions were controlled in order to maintain a defined PAEC: 42 x 10-6 J.m-3 (2 WL), in the range of domestic and environmental exposures. Animals were kept until they died or given euthanasia when moribund. Mean survival times were similar in both irradiated and control groups: 828 days (SD = 169) and 830 days (SD = 137), as well as lung cancer incidence, 0.60% at 25 WLM and 0.63% for controls. The incidence of lung lesions was compared statistically with controls and those previously obtained at cumulative exposures of 25 and 50 WLM delivered over a 4-6 month period, inducing a significant increase of lung cancer, 2.2% and 3.8% respectively. Such a comparison showed a decreased lung cancer incidence related to a decrease in the dose rate for low levels of radon exposure.


1999 ◽  
Vol 86 (5) ◽  
pp. 1696-1701 ◽  
Author(s):  
Earl G. Noble ◽  
Albert Moraska ◽  
Robert S. Mazzeo ◽  
David A. Roth ◽  
M. Charlotte Olsson ◽  
...  

High-intensity treadmill exercise increases the expression of a cardioprotective, inducible 72-kDa stress protein (SP72) in cardiac muscle. This investigation examined whether voluntary free wheel exercise training would be sufficient to confer a similar response. Male Sprague-Dawley rats were randomly assigned to either treadmill (TM-Tr) or free wheel (FW-Tr) training groups. By the end of the 8-wk training period, TM-Tr animals ran 1 h/day, 5 days/wk up a 10% grade, covering a distance of 8,282 m/wk. FW-Tr rats ran, on average, 5,300 m/wk, with one-third of the animals covering distances similar to those for the TM-Tr group. At the time of death, hearts of trained and caged sedentary control (Sed) animals were divided into left (LV) and right (RV) ventricles. Citrate synthase activity and the relative immunoblot contents of SP72, SP73 (the constitutive isoform of the SP70 family), and a 75-kDa mitochondrial chaperone (SP75) were subsequently determined. LV and RV did not differ on any measure, and SP73, SP75, and citrate synthase were not affected by training. Cardiac SP72 levels were elevated over fourfold in both ventricles of TM-Tr compared with RV of FW-Sed rats. Despite the animals having run a similar total distance, cardiac SP72 content in FW-Tr rats was not different from that in Sed animals. These data indicate that voluntary exercise training is insufficient to elicit an elevation of SP72 in rat heart and suggest that exercise intensity may be a critical factor in evoking the cardioprotective SP72 response.


1978 ◽  
Vol 235 (2) ◽  
pp. H242-H246 ◽  
Author(s):  
P. J. Baker ◽  
E. R. Ramey ◽  
P. W. Ramwell

Sex differences in the systemic depressor response to arachidonic acid (50 or 150 microgram/kg iv) were observed in intact and castrated anesthetized Sprague-Dawley rats. The rank order of responsiveness was: castrate males, castrate females, females, males; all four groups were significantly different (P less than 0.05) at the higher dose. Castrated males pretreated with testosterone (1 mg/kg sc) 5 or 7 days previously gave a response at the higher arachidonate dose levels that was of the same order as that obtained with intact males. Similar treatment of castrate males with androgen potentiated (P less than 0.05) the vasopressor action of norepinephrine (0.25 microgram/kg) on day 7 after the testosterone pretreatment. In contrast, treatment with depot estradiol (100 microgram/kg sc) in castrate males produced no significant change in the response to either of the vasoactive compounds on both days 5 and 7 after pretreatment. These data suggest that testosterone may be a significant factor in the development of sex differences in the cardiovascular systems of rats.


2007 ◽  
Vol 292 (5) ◽  
pp. F1490-F1500 ◽  
Author(s):  
Markus Schafflhuber ◽  
Nicola Volpi ◽  
Anke Dahlmann ◽  
Karl F. Hilgers ◽  
Francesca Maccari ◽  
...  

The idea that an osmotically inactive Na+ storage pool exists that can be varied to accommodate states of Na+ retention and/or Na+ loss is controversial. We speculated that considerable amounts of osmotically inactive Na+ are lost with growth and that additional dietary salt excess or salt deficit alters the polyanionic character of extracellular glycosaminoglycans in osmotically inactive Na+ reservoirs. Six-week-old Sprague-Dawley rats were fed low-salt (0.1%; LS) or high-salt (8%; HS) diets for 1 or 4 wk. At their death, we separated the tissues and determined their Na+, K+, and water content. Three weeks of growth reduced the total body Na+ content relative to dry weight (rTBNa+) by 23%. This “growth-programmed” Na+ loss originated from the bone and the completely skinned and bone-removed carcasses. The Na+ loss was osmotically inactive (45–50%) or osmotically active (50–55%). In rats aged 10 wk, compared with HS, 4 wk of LS reduced rTBNa+ by 9%. This dietary-induced Na+ loss was osmotically inactive (≈50%) and originated largely from the skin, while ≈50% was osmotically active. LS for 1 wk did not reduce skin Na+ content. The mobilization of osmotically inactive skin Na+ with long-term salt deprivation was associated with decreased negatively charged skin glycosaminoglycan content and thereby a decreased water-free Na+ binding capacity in the extracellular matrix. Our data not only serve to explain discrepant results in salt balance studies but also show that glycosaminoglycans may provide an actively regulated interstitial cation exchange mechanism that participates in volume and blood pressure homeostasis.


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