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J Lindfeldt

Publications and source records attributed to J Lindfeldt.

10 recordsLinked to original sources

A randomized study comparing manual lymph drainage with sequential pneumatic compression for treatment of postoperative arm lymphedema.

We compared manual lymph drainage (MLD) with sequential pneumatic compression (SPC) for treatment of unilateral arm lymphedema in 28 women previously treated for breast cancer. After 2 weeks of therapy with a standard compression sleeve (Part I) with maintenance of a steady arm volume, each patient was randomly assigned to either one of two treatment regimens (Part II). MLD was performed according to the Vodder technique for 45 min/day and SPC was performed with a pressure of 40-60 mmHg for 2 hours/day. Both treatments were carried out for 2 weeks. Arm volume was measured by water displacement. Arm mobility, strength, and subjective assessments were also determined. Lymphedema was reduced by 49 ml (7% reduction) (p = 0.01) in the total group during Part I. During Part II, the MLD group decreased by 75 ml (15% reduction) (p < 0.001) and the SPC group by 28 ml (7% reduction) (p = 0.03). The total group reported a decrease of tension (p = 0.004) and heaviness (p = 0.01) during Part I. During Part II, only the MLD group reported a further decrease of tension (p = 0.01) and heaviness (p = 0.008). MLD and SPC each significantly decreased arm volume but no significant difference was detected between the two treatment methods.

Aged↗

Contribution of liver nerves, glucagon, and adrenaline to the glycaemic response to exercise in rats.

The contribution of hepatic sympathetic innervation, glucagon and adrenaline to the glycaemic response to exercise was investigated in rats. Hepatically denervated (LDX) or sham operated (SHAM) rats with permanent catheters were therefore submitted to swimming with or without infusion of somatostatin in combination with adrenodemedullation. Blood samples were taken for measurements of blood glucose, plasma free fatty acids (FFA), adrenaline (A), noradrenaline (NA), insulin and glucagon. Liver denervation by itself did not influence glucose levels during exercise. Infusion of somatostatin in SHAM animals, which inhibited the exercise-induced glucagon response, led to enhanced sympathoadrenal outflow (measured as plasma A and NA) and a reduced blood glucose during exercise, suggesting that glucagon serves as a powerful mediator of the glycaemic response during swimming. Infusion of somatostatin in LDX animals failed to enhance plasma NA levels and led to a more pronounced reduction in blood glucose levels. This indicates that liver nerves do contribute to the glycaemic response to exercise when glucagon secretion is suppressed. Reduced blood glucose levels after adrenodemedullation revealed that adrenal A is another important mediator of the glucose response to exercise. Infusion of somatostatin in adrenodemedullated SHAM or LDX animals was not accompanied with increased NA outflow, suggesting that adrenal A is necessary to allow the compensatory increased outflow of NA from sympathetic nerves. In conclusion, the study shows that pancreatic glucagon and adrenal A are the predominant factors influencing the glycaemic response to exercise, whereas a role of the sympathetic liver nerves becomes evident when glucagon secretion is suppressed.

Adrenal Medulla↗

Glucose homeostasis after peri-arterial hepatic denervation in partially hepatectomized rats.

Peri-arterial hepatic denervation did not change the low basal plasma glucose levels on the 1st post-operative day in partially hepatectomized animals. On the 2nd post-operative day, the denervated animals had significantly higher basal plasma glucose levels than innervated animals. Basal plasma insulin levels were similar in both resected groups, suggesting a relative hyperinsulinemia in the innervated group. Basal plasma glucagon levels were similar in all groups on the 1st post-operative day, but were significantly raised on the 2nd post-operative day in the two resected groups. After i.v. glucose (0.5 g/kg b.w.) on the 1st post-operative day, or glucagon (10 micrograms/kg b.w.) on the 2nd post-operative day, the absolute increments and eliminations of glucose and insulin were similar in all groups. We conclude that the hypoglycemia observed after partial hepatectomy is not only due to the evident loss of glycogen stores, but is also mediated by mechanisms dependent on the peri-arterial hepatic nerves, possibly through an effect on basal plasma insulin levels.

Animals↗

Evidence for an influence of the peri-arterial hepatic nerves on basal insulin-secretion in the rat.

We studied the in vivo sensitivity of isolated pancreatic islets to glucose and glucagon 1 week after in vivo micro-surgical denervation of the peri-arterial hepatic nerves in the rat. Basal insulin secretion (at 3.3 mM glucose) was significantly higher in denervated than in sham operated or control animals (137 +/- 27 microU/ml vs. 35 +/- 2 microU/ml, P = 0.004 and 58 +/- 15 microU/ml, P = 0.041, respectively). Also after stimulation with 13.3 mM glucose, insulin secretion was significantly higher in denervated cf. to sham operated animals (388 +/- 50 microU/ml vs. 211 +/- 6 microU/ml, P = 0.005), but not significantly vs. controls (273 +/- 41 microU/ml). In contrast, when the islets were stimulated with glucagon (10(-9)-10(-5) M) at basal glucose concentrations (3.3 mM), the increment of insulin secretion was not significantly higher in the denervated animals vs. control animals. Our findings indicate the existence of a neural control mechanism of basal insulin secretion from the pancreatic islets mediated through the peri-arterial autonomic hepatic nerves.

Animals↗

Influence of peri-arterial hepatic denervation on the glycemic response to exercise in rats.

Exercise is known to increase hepatic glucose production. Previous studies have suggested that the sympathetic nerves only marginally contribute to this process. This study examined whether increased catecholamine response or increased adrenoceptor sensitivity might have affected previous results showing no effect of hepatic denervation on the increased hepatic glucose production during exercise. Hepatic sympathetic denervated rats, sham-operated rats and control rats were forced to swim against a counter current for 15 minutes. Denervations and sham operations were performed 9 days prior to swimming. The results show that denervation did not affect the changes in levels of blood glucose, plasma FFA, and catecholamines before, during and after swimming. Furthermore, hepatic adrenoceptor sensitivity was not altered in denervated rats, since intravenous infusions of epinephrine (20 ng/min) and norepinephrine (50 ng/min) similarly changed blood glucose and plasma FFA levels in liver-denervated, sham-operated and control rats. Thus, the increase in blood glucose levels during intravenous infusion of epinephrine and norepinephrine in the respective groups was 1.2 +/- 0.3 and 1.0 +/- 0.3 mmol/l (liver-denervated rats), 1.6 +/- 0.4 and 0.7 +/- 0.3 mmol/l (sham-operated rats) and 1.3 +/- 0.3 and 0.8 +/- 0.3 mmol/l (control rats), respectively. After adrenodemedullation, however, the rise of glucose levels during swimming in liver-denervated and control rats was completely abolished. Thus, the glucose response to swimming with and without adrenodemullation was 0.1 +/- 0.4 and 1.7 +/- 0.4 mmol/l in liver-denervated rats (P < 0.01) and -0.2 +/- 0.4 and 2.2 +/- 0.2 mmol/l in control rats (P < 0.001), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenalectomy↗

Hepatic sympathetic denervation potentiates glucagon-stimulated glycogenolysis and hyperinsulinaemia in the rat.

The influence of hepatic nerves on glucagon-stimulated hyperglycaemia and hyperinsulinaemia was studied in rats. Using microsurgical techniques, hepatic sympathectomy (resulting in approximately 80% reduction of liver noradrenaline content) or hepatic vagotomy was performed. Glucagon (10 micrograms/kg b.wt.) was injected i.v. one week after the operative procedure. Plasma levels of glucose and insulin rose more rapidly and to a higher level in rats subjected to hepatic sympathectomy than in sham-operated or non-operated control animals. In contrast, hepatic vagotomy did not influence the plasma glucose or insulin response to glucagon. In conclusion, our findings suggest a role for the hepatic sympathetic nerves in glucagon-stimulated glycogenolysis and insulin secretion in the rat.

Animals↗

The effect of intraportal six-hydroxy-dopamine on hemorrhage after standardized liver trauma in rats.

Sympathetic denervation of the liver was accomplished by intraportal injection of 6-hydroxy-dopamine in rats. The animals were subjected to standardized liver trauma 1 week later. Blood loss and duration of bleeding from the cut raw surface were more than doubled in the denervated animals. Mean arterial blood pressure was significantly lower in the denervated animals, but stable during hemorrhage in both denervated and innervated animals. Platelet aggregation and the intrinsic coagulation system were not affected by the chemical denervation. Hepatic norepinephrine was almost eliminated by the denervation procedure. These findings suggest that the liver nerves at the porta hepatis should be preserved during hepatic resections.

Animals↗

Hepatic lipase activity increases after liver denervation in the rat.

We have investigated the effects of hilar denervation of rat liver upon the activity of hepatic lipase determined in tissue extracts. Denervated animals had an enzyme activity of 7.89 +/- 0.37 mU/mg protein, compared to 6.45 +/- 0.43 in sham-operated controls (mean +/- S.E.; P less than 0.05). We conclude that hepatic innervation may contribute to the regulation of hepatic lipase activity.

Animals↗

A microsurgical method for denervation of the liver in the rat.

The role of the nerves in the hepato-duodenal ligament should be of special surgical interest, since these nerves are often injured in hepatic and biliary tract surgery. We have developed a microsurgical procedure for liver denervation. All visible nerves were resected after staining. Norepinephrine values in central liver tissue of denervated rats were only 18% of the corresponding values in innervated liver tissue, indicating an appreciable degree of sympathetic denervation. No detectable immunoreactivity of gastrin, cholecystokinin, vasoactive intestinal polypeptide, substance P, somatostatin or enkephalin were found within resected hepatic nerves. The described denervation procedure is simple and reproducible. It can be used to obtain additional information about the nervous regulation of various liver functions.

Animals↗