scholarly journals Hepatic carnitine palmitoyltransferase turnover and translation rates in fed, starved, streptozotocin-diabetic and diethylhexyl phthalate-treated rats

1987 ◽  
Vol 246 (3) ◽  
pp. 641-649 ◽  
Author(s):  
P S Brady ◽  
L J Brady
Keyword(s):  
Protein Synthesis ◽  
Mitochondrial Protein ◽  
Mrna Translation ◽  
Liver Weight ◽  
Diabetic Rats ◽  
Carnitine Palmitoyltransferase ◽  
Diethylhexyl Phthalate ◽  
Mild Diabetes ◽  
Streptozotocin Diabetic Rats

Hepatic carnitine palmitoyltransferase (CPT) turnover was studied in control and in non-ketotic hyperglycaemic streptozotocin-diabetic rats. The degradation constant (kd) and half-life (t1/2) did not appear to be altered by mild diabetes. The hepatic CPT (micrograms/g of liver) was not increased by the mild, non-ketotic, diabetes. However, the total hepatic CPT (micrograms/liver) was 37% greater in the diabetic animals, owing to the increased liver weight. This resulted from a 40% increase in the synthesis constant (ks). Hepatic CPT activity (total detergent-solubilized) and translation rates were measured in fed, starved (48 h), non-ketotic diabetic, ketotic diabetic and diethylhexyl phthalate (DEHP)-treated rats. CPT activity (m units/mg of mitochondrial protein) was not significantly increased with non-ketotic diabetes (44% increase, but non-significant), but was increased approx. 2-fold with starvation and ketotic diabetes, and 3.5-fold with DEHP treatment. CPT expressed as units/liver was increased non-significantly (23%) in non-ketotic and starved rats, similar to the turnover study, but was significantly increased with ketotic diabetes and with DEHP treatment. mRNA-translation activity for CPT was elevated in all states to a somewhat greater extent than was activity. It was concluded that protein synthesis as a product of increased CPT-mRNA translation activity is a major means of long-term regulation.

Altered response in renal blood flow and oxygen tension to contrast media in diabetic rats

2003 ◽  
Vol 44 (3) ◽  
pp. 347-353 ◽  
Author(s):  
F. Palm ◽  
P.-O. Carlsson ◽  
P. Hansell ◽  
O. Hellberg ◽  
A. Nygren ◽  
...  
Keyword(s):  
Blood Flow ◽  
Oxygen Tension ◽  
Blood Glucose Concentration ◽  
Diabetic Control ◽  
Diabetic Rats ◽  
Diabetic Patients ◽  
Medullary Blood Flow ◽  
Streptozotocin Diabetic Rats ◽  
Altered Response

Purpose: To investigate the effect of the contrast medium (CM) iopromide on renal microcirculation and oxygen tension in non-diabetic control and streptozotocin-diabetic Wistar Furth rats. Materials and Methods: Oxygen tension was measured with Clark-type microelectrodes and blood flow with laser-Doppler flow probes. In order to differentiate between an acutely increased blood glucose concentration and a long-term diabetic state, some of the non-diabetic control rats were intravenously infused with glucose. Results: CM decreased the medullary oxygen tension in control (non-diabetic normoglycemic) rats (∼35%) but not in diabetic rats. Medullary blood flow in control rats increased after CM administration and remained elevated, while it was unchanged in the diabetic rats. In response to CM, glucose-infused control rats responded similarly to control animals in medullary oxygen tension, but similarly to diabetic rats in medullary blood flow. Contrary to in control rats, medullary oxygen tension was unchanged in diabetic animals after CM administration. Conclusion: Streptozotocin-diabetic rats have an altered response to intravenous injection of the CM iopromide compared to non-diabetic rats. The unaltered medullary oxygen tension, seen in the diabetic group after injection of CM, suggests that non-hemodynamic mechanisms are responsible for the increased frequency of renal failure commonly seen among diabetic patients.

scholarly journals Glutamine and ketone-body metabolism in the gut of streptozotocin-diabetic rats

1988 ◽  
Vol 249 (2) ◽  
pp. 565-572 ◽  
Author(s):  
M S M Ardawi
Keyword(s):  
Small Intestine ◽  
Ketone Body ◽  
Ketone Bodies ◽  
Diabetic Rats ◽  
Glutamine Metabolism ◽  
Gut Mucosa ◽  
Streptozotocin Induced Diabetes ◽  
Streptozotocin Diabetic Rats ◽  
Short And Long Term

1. In short- and long-term diabetic rats there is a marked increase in size of both the small intestine and colon, which was accompanied by marked decreases (P less than 0.001) and increases (P less than 0.001) in the arterial concentrations of glutamine and ketone bodies respectively. 2. Portal-drained viscera blood flow increased by approx. 14-37% when expressed as ml/100 g body wt., but was approximately unchanged when expressed as ml/g of small intestine of diabetic rats. 3. Arteriovenous-difference measurements for ketone bodies across the gut were markedly increased in diabetic rats, and the gut extracted ketone bodies at approx. 7 and 60 nmol/min per g of small intestine in control and 42-day-diabetic rats respectively. 4. Glutamine was extracted by the gut of control rats at a rate of 49 nmol/min per g of small intestine, which was diminished by 45, 76 and 86% in 7-, 21- and 42-day-diabetic rats respectively. 5. Colonocytes isolated from 7- or 42-day-diabetic rats showed increased and decreased rates of ketone-body and glutamine metabolism respectively, whereas enterocytes of the same animals showed no apparent differences in the rates of acetoacetate utilization as compared with control animals. 6. Prolonged diabetes had no effects on the maximal activities of either glutaminase or ketone-body-utilizing enzymes of colonic tissue preparations. 7. It is concluded that, although the epithelial cells of the small intestine and the colon during streptozotocin-induced diabetes exhibit decreased rates of metabolism of glutamine, such decreases were partially compensated for by enhanced ketone-body utilization by the gut mucosa of diabetic rats.

scholarly journals Long-term effectiveness of oral vanadyl sulphate in streptozotocin-diabetic rats

Diabetologia ◽  
1993 ◽  
Vol 36 (3) ◽  
pp. 218-224 ◽  
Author(s):  
M. C. Cam ◽  
R. A. Pederson ◽  
R. W. Brownsey ◽  
J. H. McNeill
Keyword(s):  
Diabetic Rats ◽  
Streptozotocin Diabetic Rats ◽  
Vanadyl Sulphate

Protein synthesis in liver and small intestine in protein deprivation and diabetes

1981 ◽  
Vol 241 (3) ◽  
pp. E238-E245 ◽  
Author(s):  
M. A. McNurlan ◽  
P. J. Garlick
Keyword(s):  
Protein Synthesis ◽  
Small Intestine ◽  
Dietary Protein ◽  
Young Male ◽  
Diabetic Rats ◽  
Male Rats ◽  
Jejunal Mucosa ◽  
Protein Deprivation ◽  
Protein Pool ◽  
Streptozotocin Diabetic Rats

Protein synthesis (as a percent of the protein pool synthesized per day) has been measured in liver and small intestine of young male rats from the incorporation of 100 mumol [1–14C]leucine/100 g body wt into protein over 10 min. Dietary protein deprivation for 8 days depressed protein synthesis in liver (30%), jejunal mucosa (20%), and jejunal serosa (25%). In serosa, reduced levels of RNA relative to protein could account for altered synthesis; in liver and mucosa, the amount of protein synthesized per unit RNA was reduced. In liver of streptozotocin-diabetic rats protein synthesis was depressed 45%, whereas it was maintained in jejunal mucosa and serosa. Depressed synthesis in liver was accompanied by both a loss of RNA relative to protein and a reduction in the protein synthesized per RNA.

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