Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:Q86TM3 (cage)
 29,987 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study has evaluated insulin resistance under steady-state conditions using the glucose clamp technique. Euglycaemic clamp investigations were conducted at 4-5 different insulin levels (70-1600 mUl-1) in five malnourished cancer patients, four well-nourished Intensive Care Unit patients (ICU) and 11 well-nourished individuals. Whole body uptake of glucose was measured. In three cancer patients the flux of glucose across the leg was measured. Cancer patients had significantly reduced fasting insulin concentrations, while ICU patients had increased levels compared to controls. The fasting levels of glucose did not differ among the groups. Both insulin sensitivity and responsiveness were reduced by 50% in cancer and ICU patients. At insulin levels of 200-250 mUl-1, approximately 80% of the whole body glucose uptake could be accounted for by the peripheral tissues. This study confirms that insulin resistance is a significant metabolic alteration in cancer associated malnutrition. The results demonstrate both decreased insulin sensitivity and responsiveness.
 ...
PMID:Mechanisms of insulin resistance in cancer associated malnutrition. 353 64

Rats demonstrated that they can use deprivation-produced stimuli as discriminative signals for shock in three experiments that used observation of freezing behavior as the index of learning. In Experiment 1, one group was shocked under 24-hr, but not under 0-hr food deprivation. Another group received the reversed discrimination. Both groups froze more under their shocked than under their nonshocked deprivation level. Furthermore, freezing was greatest under a given deprivation level for the group shocked under that level. Behavior was shown to be a function of this learning during subsequent testing under other deprivation levels. In Experiment 2, rats discriminated between deprivation intensities approximating those encountered under free-feeding conditions, and behavior under other deprivation levels also depended on this learning. Experiment 3, using 6- and 23-hr food deprivation, showed that discriminative responding occurred in the absence of cues arising from the recent memory of food in the home cage. Generalization of discriminative control to cues produced by intubation of a high calorie load and to injection of insulin (Experiment 3A) provided evidence that animals learned about the interoceptive stimulus consequences of their deprivation states. The results encourage the view that learning about internal stimulus aspects of food deprivation plays a role in appetitive behavior.
 ...
PMID:Learning about deprivation intensity stimuli. 358 Jan 21

It has been suggested that the monokine tumor necrosis factor (TNF) (cachectin) is responsible for metabolic abnormalities frequently accompanying malignant neoplasms. The acute metabolic effects of TNF in patients with cancer were studied. Subcutaneous administration of recombinant human TNF led to a rise in the C-reactive protein level (4.4 +/- 1.2 mg/dL vs 11.6 +/- 1.8 mg/dL) and a reduction in the serum zinc level (12.9 +/- 0.8 mumol/L vs 7.3 +/- 0.8 mumol/L [79 +/- 5 mg/dL vs 48 +/- 5 mg/dL]) (values are the mean +/- SEM). Forearm efflux of total amino acids more than doubled after intravenous TNF injection, principally because of increases in release of the gluconeogenic amino acids alanine and glutamine. Concomitantly, the arterial levels of alanine, glutamine, and total amino acids fell, indicating that TNF also stimulated the uptake of amino acids by other tissues. The observed amino acid pattern cannot be explained solely on the basis of measured changes in cortisol, glucagon, or insulin levels. These findings are discussed in relation to known alterations of amino acid metabolism in cancer-associated cachexia.
 ...
PMID:The acute metabolic effects of tumor necrosis factor administration in humans. 368 16

Different microcalorimetric techniques have been compared for the assessment in vitro of the total metabolic activity of resting skeletal muscle. Human fibre bundles were suspended in Krebs-Ringer-phosphate buffer containing glucose and insulin and the heat evolution was continuously monitored for 2-6 h. Palmitate as substrate was also tested. The power signals declined rapidly when a static calorimetric method (A) was used. Two different perfusion methods (B, C) gave higher power values. Long-lasting steady states were observed with method C, where the sample was contained in a cage acting as a stirrer. Significant differences were found for fibre bundles from different human muscles as well as age- and sex-related differences. The heat production in samples from the rectus abdominis muscle (method B), 0.73 mW/g muscle wet wt., was significantly higher than for the obliquus internus muscle, 0.44 mW/g, and the vastus lateralis muscle, 0.55 mW/g, but not different from the heat production value of vastus medialis, 0.66 mW/g. In method C particularly, the fibre bundles are believed to be in adequate contact with the surrounding medium. With the use of a multi-channel calorimeter it is possible to perform up to four experiments simultaneously, e.g. involving the calorigenic effects of pharmacological substances. The technique provides a new approach for detailed studies of muscle metabolism in physiological and pathological conditions.
 ...
PMID:A microcalorimetric study of heat production in resting skeletal muscle from human subjects. 394 79

The effect of physical training on insulin release and glucose utilization by perifused islets and on liver glucokinase activity was examined in rats that exercised spontaneously by running (in wheel cage) up to 4-6 mi/day for 36 +/- 4 days and in sedentary controls kept in standard cages. Perifusion of islets with 4 mM glucose resulted in comparable rates of insulin release from islets obtained from trained and sedentary control rats. In contrast, when the perifusion glucose concentration was raised to 10 mM, the biphasic increase in insulin release was 40-50% lower in the trained rats as compared with untrained rats. This decrease in glucose-stimulated insulin release occurred in the face of comparable rates of glucose utilization by islets from control and trained rats. Glucose phosphorylation by liver homogenates from trained rats was reduced at all concentrations of glucose examined (0.5-100 mM). The calculated glucokinase activity was diminished by 40%, whereas hexokinase activity was decreased by 15% in the livers from trained rats. We conclude that 1) hypoinsulinemia induced by exercise training is due to decreased sensitivity of the beta-cell to the stimulant action of glucose independent of changes in islet cell utilization of glucose, and 2) exercise training results in a diminution of liver glucokinase activity that may be a consequence of the hypoinsulinemia.
 ...
PMID:Influence of physical training on insulin release and glucose utilization by islet cells and liver glucokinase activity in the rat. 675 63

The opiate antagonist naloxone reduced the food intake induced in rats by acute injection of insulin. The suppression was most marked in the first hour after insulin injection. Insulin provoked less food intake when rats were tested in a novel environment compared with those tested in their home cage, but naloxone again significantly suppressed the intake in the first hour. Naloxone had no effect upon insulin-induced hypoglycemia.
 ...
PMID:Naloxone suppresses insulin-induced food intake in novel and familiar environments, but does not affect hypoglycemia. 705 Oct 49

Pancreatic A-cell function in the newly developed Otsuka Long Evans Tokushima Fatty (OLETF) strain of non-insulin-dependent diabetes mellitus (NIDDM) rats was examined in relation to the morphological changes in their islets and the plasma glucagon responses to insulin-induced hypoglycemia and an arginine test by chronological studies in seven male OLETF and seven male non-diabetic control Long Evans Tokushima Otsuka (LETO) rats each at 10, 16 and 24 weeks of age and eight male OLETF rats that were placed in a cage with a wheel for exercising from 5 to 24 weeks of age. The hormonal contents and morphological features of the pancreas of these rats were examined. After iv injection of insulin, the plasma glucagon level rose significantly from the basal level in OLETF rats at 10 weeks old, but little if at all in those of 16 and 24 weeks old. The pancreatic A cells of LETO rats of all age groups responded equally well to glucopenia. The areas under the response curves of plasma glucagon (sigma delta IRG) during the 90 min of insulin-induced hypoglycemia were 14496 +/- 7860 vs 9588 +/- 3930, 2257 +/- 3018 vs 9235 +/- 5447 (p < 0.05) and 826 +/- 985 vs 9707 +/- 2510 (p < 0.01) ng.min-1.l-1 in OLETF rats vs LETO rats of 10, 16 and 24 weeks old, respectively. The plasma glucagon responses during the arginine test were higher in OLETF rats than in LETO rats at 10 and 16 weeks but not at 24 weeks of age.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Plasma glucagon responses to insulin-induced hypoglycemia and arginine in spontaneous non-insulin-dependent diabetes mellitus (NIDDM) rats, Otsuka Long Evans Tokushima Fatty (OLETF) strain. 810 92

The relative abundance and subcellular distribution of the GLUT-1 and GLUT-4 glucose transporter isoforms were determined in basal and insulin-stimulated adipose cells from wheel cage exercise-trained rats and compared with both age-matched sedentary controls and young cell size-matched sedentary controls. Exercise training increased total estimated GLUT-4 by 67 and 54% compared with age-matched and young controls, respectively. Total estimated GLUT-1 per cell was not significantly different among the three groups. Expressed per cell, plasma membrane GLUT-4 protein in basal adipose cells from exercise-trained and age-matched control rats was 2.5-fold greater than in young controls (P < 0.05) and was associated with higher basal rates of glucose transport in these cells (P < 0.02). In insulin-stimulated cells, plasma membrane GLUT-4 was 67% greater in the exercise-trained animals than young controls (P < 0.01), and 31% greater than in age-matched controls. Rates of glucose transport were correspondingly higher. In basal cells, low-density microsomal GLUT-4 from exercise-trained rats was approximately twofold greater than from age-matched controls and young controls. With insulin stimulation, GLUT-4 in low-density microsomes decreased to similar levels in all groups. We conclude that the total amount of GLUT-4 protein, but not GLUT-1, is increased in adipose cells by exercise training and that this increase in GLUT-4 is due primarily to an increase in intracellular GLUT-4.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Exercise training increases GLUT-4 protein in rat adipose cells. 833 13

This study was designed to examine the effect of non-weight-bearing conditions and the systemic influences of simulated microgravity on rat hindlimb muscles. For this purpose, rats were suspended (SUS) in a head-down position (45 degrees) with the left hindlimb non-weight bearing (NWB) and the right hindlimb bearing 20% of presuspension body mass (WB). Weight bearing by the SUS-WB limb was accomplished by using a platform connected to a rod in sleeve, cable, and pulley apparatus to which weight could be added. Rats (250-325 g) were assigned to SUS or cage control (CC) conditions for 14 days. The angle between the foot and leg for SUS-WB and CC remained similar (20-30 degrees) throughout the experiment while the SUS-NWB hindlimbs extended to approximately 140 degrees by day 12. On day 14, the soleus, plantaris, and gastrocnemius muscles from the SUS-NWB limbs exhibited significantly lower (P < or = 0.05) masses than presuspension mass values (29, 11, and 21%, respectively). Weight bearing by the SUS-WB limbs prevented the loss of mass by these muscles. In separate groups of SUS and CC rats, 2-deoxyglucose uptake during hindlimb perfusion was significantly higher in both SUS-NWB and SUS-WB hindlimbs at 24,000 microU/ml of insulin compared with CC for all the muscles examined (21-80%). In addition, extracellular space (ml/g) was significantly greater in the soleus muscles from both the SUS-NWB and SUS-WB hindlimbs (64%) compared with CC muscles.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Muscle glucose uptake in the rat after suspension with single hindlimb weight bearing. 833 32

Our knowledge of the effects of unweighting on skeletal muscle of juvenile rapidly growing rats has been obtained entirely by using hindlimb-suspension models. No spaceflight data on juvenile animals are available to validate these models of simulated weightlessness. Therefore, eight 26-day-old female Sprague-Dawley albino rats were exposed to 5.4 days of weightlessness aboard the space shuttle Discovery (mission STS-48, September 1991). An asynchronous ground control experiment mimicked the flight cage condition, ambient shuttle temperatures, and mission duration for a second group of rats. A third group of animals underwent hindlimb suspension for 5.4 days at ambient temperatures. Although all groups consumed food at a similar rate, flight animals gained a greater percentage of body mass per day (P < 0.05). Mass and protein data showed weight-bearing hindlimb muscles were most affected, with atrophy of the soleus and reduced growth of the plantaris and gastrocnemius in both the flight and suspended animals. In contrast, the non-weight-bearing extensor digitorum longus and tibialis anterior muscles grew normally. Earlier suspension studies showed that the soleus develops an increased sensitivity to insulin during unweighting atrophy, particularly for the uptake of 2-[1,2-3H]deoxyglucose. Therefore, this characteristic was studied in isolated muscles within 2 h after cessation of spaceflight or suspension. Insulin increased uptake 2.5- and 2.7-fold in soleus of flight and suspended animals, respectively, whereas it increased only 1.6-fold in control animals. In contrast, the effect of insulin was similar among the three groups for the extensor digitorum longus, which provides a control for potential systemic differences in the animals.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Spaceflight on STS-48 and earth-based unweighting produce similar effects on skeletal muscle of young rats. 833 44


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>