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U Angerås

Publications and source records attributed to U Angerås.

31 records · Page 2Linked to original sources
PubMed1987

Protein degradation in skeletal muscle during experimental hyperthyroidism in rats and the effect of beta-blocking agents.

beta-Blocking agents are increasingly used in the management of hyperthyroid patients. The effect of this treatment on increased muscle protein breakdown in the hyperthyroid state is not known. In the present study, experimental hyperthyroidism was induced in rats by daily ip injections of T3 (100 micrograms/100 g BW) during a 10-day period. Control animals received corresponding volumes of solvent. In groups of rats the selective beta-1-blocking agent metoprolol or the nonselective beta-blocker propranolol was infused by miniosmotic pumps implanted sc on the backs of the animals. Protein degradation was measured in incubated intact soleus and extensor digitorum longus muscles by determining tyrosine release into the incubation medium. The protein degradation rate in incubated extensor digitorum longus and soleus muscles was increased by 50-60% during T3 treatment. Metoprolol or propranolol did not influence muscle protein breakdown in either T3-treated or control animals. The results suggest that T3-induced increased muscle proteolysis is not mediated by beta-receptors, and muscle weakness and wasting in hyperthyroidism might not be affected by beta-blockers.

Adrenergic beta-Antagonists↗
PubMed1986

The effect of beta-adrenergic blockade on the myopathic changes in experimental hyperthyroidism in rats.

Hyperthyroidism is frequently associated with myopathy. Beta-blocking agents, which are increasingly used in the treatment of hyperthyroidism, have been reported to have a possible beneficial effect on thyrotoxic myopathy. We have studied the myopathic changes in experimental hyperthyroidism in rats and the effect of the beta-blocking agents metoprolol and propranolol on these changes. During experimental hyperthyroidism, conversion of type 1 to type 2 fibres and accumulation of intracellular lipid, increased amounts of mitochondria, and reduced size of muscle fibers were noticed. None of these changes were prevented by metoprolol or propranolol. The results indicate that histochemical and morphological changes in skeletal muscle induced by thyroid hormone are not mediated by beta-receptors. The results of this investigation make dubious a beneficial effect of beta-blocking agents on thyrotoxic myopathy.

Adrenergic beta-Antagonists↗
PubMed1986

Effects of thyroid hormone and beta-blocking agents on plasma amino acids in rats.

Experimental hyperthyroidism was induced in rats by daily intraperitoneal injections of triiodothyronine (T3; 100 micrograms/100 g bw) for 3 days (short-term experiment) or by subcutaneous injections of T3 (30 micrograms/100 g bw) on alternate days during 6 weeks (long-term experiment). Control rats received corresponding volumes of solvent. Groups of rats were fed normal pellets or pellets enriched with the selective beta-1-blocker metoprolol (8.8 mmol/kg of diet) or with the non-selective beta-blocker propranolol (3.3 mmol/kg of diet). Plasma amino acids were determined 24 hours after the last T3 injection. In the short-term experiment, most individual amino acids were increased in T3-treated rats, also if beta-blocker had been given, but the increase in plasma concentration of some amino acids (valine, leucine, lysine and histidine) was prevented by propranolol. In the long-term experiment, several amino acids showed reduced plasma concentration during T3 treatment, also when the rats received beta-blocker. The plasma concentration of threonine, however, was normalized by propranolol during T3 treatment. The results indicate that metabolic alterations induced by T3 and producing changes in plasma amino acid concentrations are mainly unaffected by beta-blockade. However, as some plasma amino acid changes were prevented by propranolol but not by metoprolol, certain T3-induced metabolic derangements may be beta-2-receptor mediated.

Amino Acids↗
PubMed1985

Protein turnover in different types of skeletal muscle during experimental hyperthyroidism in rats.

Experimental hyperthyroidism was induced in rats by daily ip injection of triiodothyronine (T3; 100 micrograms/100 g body weight) during 3 or 10 days. Protein synthesis and degradation were measured in incubated soleus and extensor digitorum longus (EDL) muscles by determining rate of tyrosine incorporation into protein and release of tyrosine to the incubation medium respectively. Protein synthesis was unaffected by T3 administration during 3 or 10 days. Protein breakdown was significantly increased in soleus but unchanged in EDL in the 3-days experiment. Following administration of T3 for 10 days proteolysis was increased in both muscles. Weight of the soleus muscle was reduced after T3 for 3 days. After 10 days weight and protein content were reduced in both muscles. The study demonstrated that reduced muscle protein content following administration of T3 was the result of increased proteolysis, not decreased protein synthesis. The results further indicate that slow muscle (soleus) is more sensitive to the effects of thyroid hormone than fast muscle (EDL).

Animals↗
PubMed1985

Penetrating wounds of the neck. Experience from a Swedish hospital.

Stab wounds of the neck were retrospectively studied in 28 patients. Neck stabbings constituted 9% of all stab wounds recorded during the same period. Vascular injuries were most frequent, and the mortality rate was 14%. The management of neck stab wounds is discussed and three cases are presented to illustrate the difficulties and pitfalls. It is proposed that all wounds penetrating the platysma should be explored in general anaesthesia.

Adult↗
PubMed1984

Acute gastric hemorrhage secondary to wandering spleen.

A patient presenting with acute life-threatening upper gastrointestinal hemorrhage caused by a wandering spleen is reported. Emergency laparotomy revealed profuse gastric bleeding, large engorged varicose veins in the gastric wall, and a normal liver parenchyma. Gastroscopy after arrest of the hemorrhage showed varicose veins in the fundus without esophageal varices. Angiography revealed an ectopic spleen, occlusion of the splenic vein, and large venous collaterals in the gastric fundus. Elective splenectomy was performed. Wandering spleen as a cause of left-sided portal hypertension, also referred to as segmental splenic hypertension, is discussed.

Acute Disease↗
PubMed1984

Protein metabolism in skeletal muscle tissue from hyperthyroid patients after preoperative treatment with antithyroid drug or selective beta-blocking agent. Results from a prospective, randomized study.

Protein metabolism in skeletal muscle tissue was studied in three groups of patients undergoing thyroid surgery: group I (n = 8), hyperthyroid patients preoperatively treated with an antithyroid drug and T4; group II (n = 8), hyperthyroid patients preoperatively treated with the beta 1-selective adrenoreceptor blocking agent metoprolol; group III (n = 5), euthyroid patients operated on for nodular goiter or adenoma. The study was prospective and hyperthyroid patients were randomly allocated to one of the two preoperative regimens. During operation a biopsy was taken from the sternohyoid muscle and rates of protein synthesis and degradation were measured in incubated muscle tissue. Clinical improvement was equal in the two groups of hyperthyroid patients during preoperative treatment but serum T3 concentrations remained elevated in patients treated with metoprolol. Thus, these patients were biochemically hyperthyroid at the time of operation. The rate of protein degradation was significantly higher in hyperthyroid patients treated with metoprolol than in patients of groups I and III. A significant positive correlation was found between serum T3 and rate of protein degradation in skeletal muscle. Protein synthesis rates were similar in the three groups of patients. This study demonstrated for the first time increased proteolysis in skeletal muscle tissue from patients with high serum T3 concentrations. The results indicate that changes of skeletal muscle protein metabolism in hyperthyroid patients are not normalized by beta 1-blockade despite the fact that this treatment effectively controlled symptoms and signs of hyperthyroidism.

Adrenergic beta-Antagonists↗
PubMed1984

The possible role of circulating catecholamines in the control of gastric function in health and duodenal ulcer disease.

The relation between gastric acid secretion and plasma concentrations of adrenaline, noradrenaline, dopamine and gastrin was investigated in normal volunteers, adrenalectomized subjects and patients with duodenal ulcer (DU) during digestion and in response to insulin and modified sham feeding (MSF). Basal plasma noradrenaline concentrations were significantly higher in DU patients than in normals whereas basal plasma adrenaline and dopamine concentrations were low in both groups. Basal acid output was similar in the two groups. Insulin markedly increased plasma adrenaline in controls but had no discernible effect in adrenalectomized subjects. Still, there was no difference between acid secretion in the two groups. Insulin, but not MSF, caused a marked increase in plasma catecholamine concentrations in DU patients whereas the acid responses were the same. The significantly increased plasma noradrenaline concentration in DU patients was normalized 6 weeks after highly selective vagotomy but tended to return to the preoperative value 1 year postoperatively. Our results suggest that endogenously released adrenaline might affect gastric function only when present in extremely high plasma concentrations. The pathophysiological role of noradrenaline in DU disease remains obscure.

Catecholamines↗
PubMed1983

Primary anorectal malignant melanoma.

Eleven patients with primary anorectal melanoma were analyzed retrospectively. Clinical symptoms and signs were rather unspecific; bleeding in nine, a palpable mass in five, and local pain in three patients. Two patients had the tumor diagnosed accidentally. In all patients the primary tumor was in an advanced stage. A summary of the histopathological characteristics is given in all patients. Six patients were subjected to abdominal perineal resection, four to local excision, and one to a colostomy followed by radiotherapy. All patients developed metastatic disease after a median time of 10 months. The median survival time was 14 months after both abdominal perineal resection and local excision. One patient is still alive after 11 years. Pertinent data form the literature are given.

Adult↗
PubMed1983

The role of catecholamines in the control of gastric acid secretion during insulin hypoglycaemia and modified sham feeding.

The modified sham feeding procedure has been advocated to replace the insulin test as the method of choice for the assessment of denervation after vagotomy. One of the reasons for this changing attitude is the assumption that insulin hypoglycaemia causes non-cholinergic stimulation of acid secretion, possibly mediated via the sympatho-adrenal system. This study has therefore compared the effects of these two different tests on acidity and release of catecholamines into the circulation in 7 duodenal ulcer patients 6 weeks after highly selective vagotomy. It was found that insulin, but not modified sham feeding, caused a marked increase in plasma adrenaline and noradrenaline concentrations whereas gastric acid secretion was of a similar magnitude in the two tests. The results suggest that the increased plasma catecholamine levels during insulin hypoglycaemia do not influence gastric acid secretion in duodenal ulcer patients.

Adult↗
PubMed1982

Effects of food on plasma catecholamine and gastrin levels in patients with duodenal ulcer and normal volunteers.

Changes in plasma concentrations of adrenaline, noradrenaline, dopamine and gastrin in response to a standard meal were studied in 6 normal volunteers and 8 patients with chronic duodenal ulcer (DU) disease. Before the meal plasma gastrin and noradrenaline, but not adrenaline or dopamine, were higher in DU patients than in the controls. Food induced significant increments in plasma gastrin and noradrenaline concentration in both groups, whereas plasma adrenaline and dopamine levels remained unchanged. Plasma gastrin and noradrenaline concentrations were higher in DU patients than in the normal controls both during and after the meal. The results do not support the hypothesis that adrenaline is involved in the pathogenesis of duodenal ulcer disease, whereas the role of the increased plasma noradrenaline concentrations in this disease remains unclear.

Adult↗