Consequences of weight cycling in obese spontaneously hypertensive rats

1996 ◽  
Vol 270 (4) ◽  
pp. R864-R872 ◽  
Author(s):  
P. Ernsberger ◽  
R. J. Koletsky ◽  
J. S. Baskin ◽  
L. A. Collins
Keyword(s):  
Body Weight ◽  
Spontaneously Hypertensive Rat ◽  
Metabolic Efficiency ◽  
Rapid Weight Loss ◽  
Weight Cycling ◽  
Very Low Calorie Diet ◽  
Final Body Weight ◽  
Spontaneously Hypertensive ◽  
Calorie Diet ◽  
Ad Libitum

We mimicked human weight cycling in the obese spontaneously hypertensive rat (SHROB) model of genetic obesity. A 12-day very low calorie diet (VLCD; 16.7% of baseline calories) was alternated with 4-6 wk of ad libitum chow refeeding for three cycles. Control SHROB ate chow ad libitum. VLCD induced rapid weight loss, but during refeeding all the lost weight was regained. Final body weight was higher in cycled rats than in ad libitum controls (149 +/- 5 vs. 117 +/- 7% of initial baseline). Less weight was lost as a percent of starting body weight during each successive VLCD, which could not be explained by aging. At death, retroperitoneal fat pads were heavier in cycled SHROB than in ad libitum controls (62 +/- 3 vs. 44 +/- 4 g). During the first 2 days after each VLCD, cycled rats overate significantly relative to ad libitum controls (88 +/- 2 vs. 78 +/- 3 kcal/day), but cumulative food intake throughout the duration of the experiment did not differ (11.4 +/- 0.6 vs. 11.7 +/- 0.1 Mcal). Compared with ad libitum-fed rats, food efficiency (g body wt gain/kcal) was increased during each refeeding period. Weight cycling elevated blood pressure above the initial baseline throughout refeeding. Refeeding hypertension was abolished by ganglionic blockade with chlorisondamine. Thus weight cycling in SHROB exacerbates obesity, metabolic efficiency, abdominal fat accumulation, sympathetic activity, and hypertension.

Voiding behavior in awake unrestrained untethered spontaneously hypertensive and Wistar control rats

2021 ◽  
Author(s):  
Christopher L Langdale ◽  
Danielle J Degoski ◽  
Philip H Milliken ◽  
Warren M. Grill
Keyword(s):  
Body Weight ◽  
Water Consumption ◽  
Genetic Model ◽  
Spontaneously Hypertensive Rat ◽  
Infusion Pump ◽  
Bladder Capacity ◽  
In Vivo Studies ◽  
Spontaneously Hypertensive ◽  
Voided Volume

The spontaneously hypertensive rat (SHR), a genetic model of high blood pressure, has also been studied as a potential model of overactive bladder (OAB). In vivo studies confirmed the presence of surrogate markers of OAB, including detrusor overactivity (DO), increased urinary frequency, decreased bladder capacity and voided volume, and afferent hypersensitivity to bladder irritation. However, these observations were during awake cystometry (CMG) using implanted bladder catheters tethered to an infusion pump and artificially filled. We conducted studies in awake unrestrained untethered age-matched female SHR and Wistar rats to quantify naïve consumption and voiding behavior and the effect of capsaicin desensitization on consumption and voiding behavior. Food and water consumption, body weight, voiding frequency (VF), and voided volume (VV) were recorded. Rats were placed in metabolism cages for 24 h, up to twice a week, from 17 to 37 weeks of age. In SHRs, body weight, food, and water consumption were decreased compared to Wistars. However, after normalizing for body weight, only water consumption was reduced. Wistars exhibited a diurnal pattern of voiding behavior. Compared to Wistars, SHRs showed smaller VV and lacked a diurnal voiding pattern such that VV was similar during both light cycles. No difference in VF was observed after normalizing for water consumption. We observed no change in SHR voiding behavior following capsaicin desensitization, which was in contrast to a prior awake in vivo cystometry study describing increased VV and micturition interval in SHRs, and suggests that C-fiber activity may not contribute to bladder hypersensitivity in SHRs.

Analysis of BP response and Ca2+ metabolism using the saturation kinetics model

1987 ◽  
Vol 253 (3) ◽  
pp. R501-R508
Author(s):  
N. Karanja ◽  
J. A. Metz ◽  
L. P. Mercer ◽  
D. A. McCarron
Keyword(s):  
Blood Pressure ◽  
Body Weight ◽  
Bone Density ◽  
Spontaneously Hypertensive Rat ◽  
Kinetics Model ◽  
Maximal Dose ◽  
Spontaneously Hypertensive ◽  
Rates Of Change ◽  
Saturation Kinetics ◽  
Serum Ionized Calcium

The provision of supplemental dietary calcium (dCa) lowers blood pressure (BP) in the spontaneously hypertensive rat (SHR). Whether calcium's antihypertensive effects can be expressed in the presence of potentially hypertensinogenic nutrients is not known. Furthermore, the amount of dCa required to attenuate hypertension in the SHR remains undetermined. Along with establishing the effects of dCa on BP under conditions of a high Na+ intake, we sought to define the lowest dose of dCa associated with the greatest attenuation in arterial pressure in the young SHR. Thirty-five 6-wk-old SHR were fed one of five diets containing either 0.1, 0.25, 0.5, 1.0, or 2.0% dCa. All diets contained 1.0% Na+. The rates of change (delta) in body weight, BP, and serum ionized calcium were determined between 6 and 20 wk of age. Bone density (BD) was measured only at 20 wk of age. The data were analyzed using the saturation kinetics model. Results indicate that the half-maximal dose (K50) of dCa needed to lower pressure is 0.67 +/- 0.18%, which is higher than the K50 for weight (0.23 +/- 0.18) and BD (0.36 +/- 0.22). It is concluded that supplemental dCa lowers BP despite a high Na+ intake. Furthermore, a dose of approximately 1.5 dCa is sufficient to attenuate the rate of hypertension in the young growing SHR.

scholarly journals Protocol for a randomised controlled trial of the combined effects of the GLP-1 receptor agonist liraglutide and exercise on maintenance of weight loss and health after a very low-calorie diet

BMJ Open ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. e031431
Author(s):  
Simon Birk Kjær Jensen ◽  
Julie Rehné Lundgren ◽  
Charlotte Janus ◽  
Christian Rimer Juhl ◽  
Lisa Møller Olsen ◽  
...  
Keyword(s):  
Weight Loss ◽  
Body Weight ◽  
Receptor Agonist ◽  
Controlled Trial ◽  
Good Clinical Practice ◽  
Study Groups ◽  
Very Low Calorie Diet ◽  
Low Calorie ◽  
Low Calorie Diet ◽  
Calorie Diet

IntroductionThe success rate of weight loss maintenance is limited. Therefore, the purpose of this study is to investigate the maintenance of weight loss and immunometabolic health outcomes after diet-induced weight loss followed by 1-year treatment with a glucagon-like peptide-1 receptor agonist (liraglutide), physical exercise or the combination of both treatments as compared with placebo in individuals with obesity.Methods and analysisThis is an investigator-initiated, randomised, placebo-controlled, parallel group trial. We will enrol expectedly 200 women and men (age 18–65 years) with obesity (body mass index 32–43 kg/m2) to adhere to a very low-calorie diet (800 kcal/day) for 8 weeks in order to lose at least 5% of body weight. Subsequently, participants will be randomised in a 1:1:1:1 ratio to one of four study groups for 52 weeks: (1) placebo, (2) exercise 150 min/week+placebo, (3) liraglutide 3.0 mg/day and (4) exercise 150 min/week+liraglutide 3.0 mg/day. The primary endpoint is change in body weight from randomisation to end-of-treatment.Ethics and disseminationThe trial has been approved by the ethical committee of the Capital Region of Denmark and the Danish Medicines Agency. The trial will be conducted in agreement with the Declaration of Helsinki and monitored to follow the guidelines for good clinical practice. Results will be submitted for publication in international peer-reviewed scientific journals.Trial registration number2015-005585-32

Pathogenesis of abnormal acid–base balance in the young spontaneously hypertensive rat

1988 ◽  
Vol 75 (1) ◽  
pp. 29-34 ◽  
Author(s):  
Philip A. Lucas ◽  
Bernard Lacour ◽  
Lydie Comte ◽  
Tilman Drüeke
Keyword(s):  
Body Weight ◽  
Spontaneously Hypertensive Rat ◽  
Intraperitoneal Administration ◽  
Urinary Sodium ◽  
Ammonium Ion ◽  
Spontaneously Hypertensive ◽  
Plasma Bicarbonate ◽  
Phosphate Excretion ◽  
Blood Ph ◽  
Acid Loading

1. We have previously reported reduced blood pH and plasma bicarbonate in young Okamoto–Aoki spontaneously hypertensive rats (SHR) compared with normotensive Wistar–Kyoto rats (WKY). Acid loading with 1.5% (w/v) NH4Cl as the sole drinking fluid produced identical falls in blood pH, the difference remaining significant. 2. The ability of SHR to excrete acid and alkaline loads was compared with that of WKY under metabolic cage conditions. The effects of such manipulations on urinary sodium, potassium, calcium and phosphate excretion were also determined. 3. No difference was found in the ability to excrete an acid load or to reduce urine pH. Neither total urinary ammonium ion nor titratable acid differed significantly between the strains under either baseline or acid-loading conditions. 4. Baseline urinary bicarbonate excretion was not significantly different between strains but intraperitoneal administration of NaHCO3 at 2.0 mmol/kg body weight resulted in enhanced excretion in the SHR (SHR vs WKY: 625.2±71.5 vs 381.8±40.6 μmol 24h−1 kg−1 body weight, P < 0.01, mean±sem). 5. No difference in urinary sodium or potassium excretion was observed between SHR and WKY, but basal calcium and phosphate excretion were reduced in SHR (P < 0.05). 6. Increased urinary bicarbonate excretion in the presence of significantly reduced plasma bicarbonate suggests reduced tubular reabsorption of bicarbonate, which may contribute to the mild metabolic acidosis in young SHR.

scholarly journals Very low-calorie diet in candidates for bariatric surgery: change in body composition during rapid weight loss

Clinics ◽  
2019 ◽  
Vol 74 ◽  
Author(s):  
Marcela Pires Serafim ◽  
Marco Aurelio Santo ◽  
Alexandre Vieira Gadducci ◽  
Veruska Magalhães Scabim ◽  
Ivan Cecconello ◽  
...  
Keyword(s):  
Bariatric Surgery ◽  
Weight Loss ◽  
Body Composition ◽  
Rapid Weight Loss ◽  
Very Low Calorie Diet ◽  
Low Calorie ◽  
Low Calorie Diet ◽  
Calorie Diet

The Herbal Medicine Tian Ma Gou Teng Yen Alters the Development of High Blood Pressure in the Spontaneously Hypertensive Rat

1989 ◽  
Vol 17 (03n04) ◽  
pp. 211-219 ◽  
Author(s):  
Ting-Xin Zhang ◽  
Yu-Fen Wang ◽  
John Ciriello
Keyword(s):  
Body Weight ◽  
Spontaneously Hypertensive Rat ◽  
Urine Volume ◽  
Herbal Therapy ◽  
General Development ◽  
Spontaneously Hypertensive ◽  
Hypertensive Rat ◽  
Food And Water Intake ◽  
Vasomotor Activity ◽  
Herbal Prescription

In this study. the effect of the herbal prescription Tian Ma Gou Teng Yen (TGY), which is traditionally used to treat certain diseases associated with elevated arterial pressure (AP), on the general development of hypertension was investigated in the spontaneously hypertensive rat (SHR). An aqueous extract of TGY was given orally (0.5 ml/100g body weight) to 5 week old SHR twice a day for six consecutive days followed by one day without herbal therapy. The herbal prescription was administered until the SHR were 16 weeks of age. Admininstration of TGY significantly altered the development and prevented hypertension in SHR. On the other hand, heart rat, body weight, food and water intake, and urine volume and electrolytes were not altered. These data suggest that the effect of TGY on AP was through an action of TGY on sympathetic vasomotor activity.

The effect of rate of weight loss on erythrocyte glutathione concentration and synthesis in healthy obese men

2002 ◽  
Vol 102 (5) ◽  
pp. 569-577 ◽  
Author(s):  
Peter FABER ◽  
Alexandra M. JOHNSTONE ◽  
Eileen R. GIBNEY ◽  
Marinos ELIA ◽  
R. James STUBBS ◽  
...  
Keyword(s):  
Weight Loss ◽  
Risk Factor ◽  
Oxidative Modification ◽  
Synthesis Rate ◽  
Rapid Weight Loss ◽  
Very Low Calorie Diet ◽  
Low Calorie ◽  
Low Calorie Diet ◽  
Calorie Diet ◽  
Obese Subjects

Obesity is commonly associated with a high incidence and prevalence of dyslipidaemia, cardiovascular disease and Type II diabetes. Interestingly, studies have also reported decreased antioxidant levels in obese subjects. This may constitute an independent risk factor in the pathogenesis of coronary artery disease as obese subjects would have a decreased capacity to prevent the oxidative modification of low-density lipoproteins, which is a mechanism suggested as central to the development of atherogenesis. As part of a study to investigate responses to weight loss, we have assessed the effects on GSH status of a decrease in body mass of 5%, either after 6 days of complete starvation or 11 days of a very low calorie diet (2.55MJ/day). There were significant differences between the two groups in the synthesis rate of erythrocyte GSH in response to weight loss. Both the fractional and the erythrocyte synthesis rate of GSH decreased significantly (P<0.01) in the starvation group by 22% and 16% respectively. In contrast, no change in synthesis rates was observed in the very low calorie diet group (P>0.05). Total erythrocyte concentration of GSH was unaffected by the weight loss within both groups. These results suggest that erythrocyte GSH synthesis is depressed in response to a very rapid weight loss induced by fasting. An acute reduction in GSH synthesis in response to a rapid weight loss may constitute a risk factor during periods of increased GSH demands.

Effects of weight cycling in rats allowed a choice of diet

1993 ◽  
Vol 264 (1) ◽  
pp. R35-R40 ◽  
Author(s):  
G. W. Reed ◽  
G. Cox ◽  
F. Yakubu ◽  
L. Ding ◽  
J. O. Hill
Keyword(s):  
Body Weight ◽  
Body Fat ◽  
Dietary Fat ◽  
Fat Intake ◽  
Weight Cycling ◽  
Negative Effects ◽  
Percentage Body Fat ◽  
Dietary Fat Intake ◽  
Female Wistar Rats ◽  
Ad Libitum

We examined the effects of weight cycling, produced by bouts of weight loss and regain, on body weight, body composition, dietary fat intake, and energy efficiency. Three groups of adult female Wistar rats were followed for 116 days: control rats (n = 10) were allowed ad libitum access to three mixed diets with protein as a constant proportion of energy and fat provided at 10, 30, and 50% of energy; cycled rats (n = 10) had four bouts of food restriction (50% of baseline intake for 10 days) and refeeding (18-20 days of ad libitum access to the 3 mixed diets); maturity controls (n = 10) were treated identically to controls during the first two cycles and identical to cyclers during the final two weight cycles. At the end of the experiment, we could identify no negative effects of weight cycling on any of the measures taken, and in fact body weight and percentage body fat were lower in cyclers than controls. Dietary fat intake was not altered by weight cycling. In summary, weight cycling did not promote body weight or body fat gain.

Clinical Impact of a 6-Week Preoperative Very Low Calorie Diet on Body Weight and Liver Size in Morbidly Obese Patients

2013 ◽  
Vol 23 (10) ◽  
pp. 1624-1631 ◽  
Author(s):  
Jordán González-Pérez ◽  
Sofía Sánchez-Leenheer ◽  
Alfredo Rivas Delgado ◽  
Lizbeth González-Vargas ◽  
Mariana Díaz-Zamudio ◽  
...  
Keyword(s):  
Body Weight ◽  
Clinical Impact ◽  
Morbidly Obese ◽  
Obese Patients ◽  
Very Low Calorie Diet ◽  
Liver Size ◽  
Low Calorie ◽  
Low Calorie Diet ◽  
Calorie Diet

Estimation of body composition changes during weight cycling by bioelectrical impedance analysis in rats

1993 ◽  
Vol 74 (5) ◽  
pp. 2092-2098 ◽  
Author(s):  
J. Ilagan ◽  
V. Bhutani ◽  
P. Archer ◽  
P. K. Lin ◽  
K. L. Jen
Keyword(s):  
Body Composition ◽  
Body Weight ◽  
Bioelectrical Impedance Analysis ◽  
Subcutaneous Fat ◽  
Bioelectrical Impedance ◽  
Impedance Analysis ◽  
Weight Cycling ◽  
High Fat ◽  
Ad Libitum ◽  
Ad Libitum Feeding

The effects of body weight cycling (WC) in rats on body composition (BC) and feeding efficiency were studied. The usefulness of estimating BC by bioelectrical impedance analysis (BIA) was also examined. Female Sprague-Dawley rats were divided into high-fat ad libitum feeding, either noncycling or cycling, or restricted feeding (75% of control feed) cycling groups. Control rats were fed a regular laboratory ad libitum diet and did not cycle. All rats were killed at the end of week 61. A BIA unit was used at each stage of WC to obtain resistance and reactance readings. Final BC was determined by chemical analysis. On the basis of the final chemical analysis and BIA measurements, an equation was established and applied to estimate BC at each stage of WC: fat-free mass (g) = 0.38 x body wt (g) + 13.8 x [length (cm)2/resistance] + 70.9 (r = 0.95, P < 0.001). High-fat ad libitum feeding induced rapid body weight and fat gains as well as an elevated feeding efficiency and an internal fat-to-subcutaneous fat ratio, regardless of whether the rats cycled. This change in fat mass was clearly detected by the BIA. Although rats fed restricted diets had similar body weights as did control rats, they had a significantly higher internal fat-to-subcutaneous fat ratio. Thus, not only the amount of food but also the composition of the diet is important for proper weight management. The BIA method is capable of detecting the body fat mass change during WC.

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