Emotional reactivity and sympatho-adrenal activity in the rat (author's transl)

Using the open-field test, differences in emotional reactivity were shown in male rats of several albino strains. These behavioural differences were then investigated in relation to physiological differences. It was found that, under resting conditions, sympatho-adrenomedullary activity as estimated by urinary catecholamine excretion and adrenal catecholamine content is lower in the more emotionally reactive rats. The resting heart rate is correspondingly slower in these animals though they show the same noradrenaline cardiac concentration as the nonreactive rats. These data suggest that high defecating rats in the open-field exhibit a lower sympathetic tonus, possibly linked, however, with a higher parasympathetic tonus.     

Prevalence and progression of carbohydrate disorders in patients with pheochromocytoma/paraganglioma: retrospective single-center study

BackgroundCarbohydrate disorders are the most frequent metabolic disorders, affecting a significant proportion of patients with pheochromocytoma.ObjectiveA retrospective study assessed the prevalence and progression of carbohydrate disorders in 204 patients (92 men, 112 women) with histologically proven pheochromocytoma diagnosed in a single specialized tertiary center during a 40-year period (1978–2017). One hundred were followed-up after tumor removal.ResultsCarbohydrate disorders were diagnosed in 49.5% of cases: 30.4% with diabetes and, 19.1% prediabetes. Subjects with carbohydrate disorders had significantly greater age at diagnosis and higher 24-hour urine metanephrine and normetanephrine concentrations than those with normal glucose tolerance. One-third of patients with diabetes achieved good glycemic control under oral treatment (54% on metformin monotherapy). One-third of patients overall required preoperative insulin treatment. Postoperative follow-up (100 patients; 5-year mean duration) showed reduced prevalence of diabetes (13% vs. 33%; P = 0.0007) and prediabetes (12% vs. 24%; P = 0.027). Almost 60% of subjects initially diagnosed with carbohydrate disorders recovered normal glucose tolerance after surgery; these subjects had significantly higher preoperative urine metanephrine/normetanephrine levels than those with persistent diabetes/prediabetes. Correlation analysis revealed a moderate negative relationship between urine metanephrine/normetanephrine concentration and the outcome of the carbohydrate disorders (Spearmen's Rho = − 0.507; P = 0.013). There was no significant difference according to pre- or postoperative prevalence of obesity (15% vs. 16%; P = 0.845) or dyslipidemia (46% vs. 39%; P = 0.316).ConclusionsCarbohydrate disorders affect approximately 50% of pheochromocytoma patients; 30% develop overt diabetes, which may be the only clinical manifestation in some rare cases. Pheochromocytoma-related diabetes is more likely to affect patients with predominant adrenaline secretion. It is often easy to control and usually requires oral antidiabetic treatment. Reversibility of carbohydrate disorders depend on severity, preoperative metanephrine level, age and weight.     

Facteurs de la variation de la fréquence cardiaque maximale: hypothèse «enképhalinique

To try to explain the decrease in maximal heart rate under different situations (ie, chronic hypoxia, ageing, proteino-energetic malnutrition), cardiac concentration and flow of leucine-encephalin peptide in isolated and perfused hearts were studied in rats. The heart leucine-encephalin concentration which was 301 ± 60 fmol/g before perfusion, increased up to 543 ± 125 fmol/g after perfusion (1 h). The total release during perfusion was four times the initial concentration. Concerning the antagonism of leucine-encephalin on cardiotropic adrenergic effects on isolated cardiomyocytes, it is possible to propose this mechanism to explain totally or partially the decrease in maximal heart rate under particular situations.     

Alteration in sympathoadrenergic activity at rest and during intense exercise despite normal aerobic fitness in late pubertal adolescent girls with type 1 diabetes

BACKGROUND: An impaired sympathoadrenergic response to hypoglycaemic episodes has been described in young Type 1 diabetic subjects. It is unknown if this altered response occurs with exercise, and if it could influence aerobic power. METHODS: Body composition (skinfold thickness), physical activity (questionnaire) and aerobic power (PWC170 and VO2max) were assessed in 19 post-menarcheal Type 1 diabetic (T1D) girls (13.3-18.2 years) and 19 healthy siblings. At rest and at each stage of the graded exhaustive exercise, plasma glucose, insulin, epinephrine and norepinephrine, were monitored via an intravenous catheter. RESULTS: Only when expressed per kilograms of body weight, was aerobic power impaired in T1D girls compared to controls, probably because they were overweight. Throughout exercise, plasma glucose remained stable while plasma insulin decreased in the healthy girls, whereas glucose diminished significantly with no change in plasma insulin in T1D girls. During exercise catecholamines increased in the same way in both groups. However, at rest and throughout all stages of exercise, norepinephrine levels were significantly lower by a mean difference of 1.2 nmol/L, while epinephrine levels were significantly higher by a mean difference of 0.14 nmol/L, in T1D girls compared to healthy girls. Heart rates of T1D girls were not affected by the sympathoadrenergic alteration. CONCLUSION: T1D adolescent girls display an altered sympathoadrenergic activity at rest and during intense exercise. Their reduced sympathetic activity, albeit probably compensated for by higher adrenomedullary responsiveness or sensitivity, does not affect their heart rate adaptations to exercise.     

Paragangliomas: clinical and secretory profile. Result of 39 cases

THIS RETROSPECTIVE STUDY AIMS: To define a clinical and secretory profile of paragangliomas extra-adrenal chromaffin tumors. METHODS: From 1971 throughout 2002, 39 paragangliomas have been observed in 38 patients (22 male, 16 female, average age 41,2 years). RESULTS: Four were located above the diaphragm, 35 were sub-phrenic (6 of the organ of Zuckerkandl), 32 secreted catecholamines, 23 were hypertensive (with only one without hypersecretion of catecholamines). Among 29 (131)I-metaiodobenzylguanidine scans (MIBG) reviewed, 20 tumors took up the radiopharmaceutical. The treatment was surgical in 35 cases with addition of external radiotherapy and MIBG in one case each; two patients died before any treatment. Two patients with persistent disease after surgery were successfully treated by surgery or MIBG. Histologically, 20 were malignant and 17 were seemingly benign. All exclusive dopamine secreting paragangliomas were malignant. Six patients relapsed two of which for a tumor initially classified as benign. The treatment of recurrences was surgical, by MIBG or by external radiotherapy. Nine patients had a family history of chromaffin tumor(s). The genetic survey made in five of these nine patients was positive in all cases.     

The shearing stress of baseball–spontaneous coronary artery dissection in a male athlete

The following is a case report of an atypical presentation of spontaneous coronary artery disease. In this case, a male with risk factors, precipitated by an emotional stress, presented to the emergency room with atypical chest pain. Cardiac catheterization revealed tapering of the mid-left anterior descending artery, consistent with non-atherosclerotic spontaneous coronary artery disease. However due to repeat chest pain, a repeat cardiac catheterization was performed, revealing 100% occlusion of the mid-LAD. This case represents an atypical presentation of a pathology that is frequently missed, and underreported. This is important to discuss in order to increase awareness, as the management and follow up are actually conservative.     

Modification de la lipolyse du tissu adipeux après un entraînement en endurance chez des sujets obèses

This study investigates the effect of a 3 month endurance training on in vitro adipose tissue lipolysis in 13 obese men (body mass index: 36.9 ± 1.3 kg/m²). Training decreased body fat mass percentage (P < 0.05), without body weight change. Lipolytic effects of epinephrine, isoproterenol (β-adrenoceptor agonist) and dobutamine (β₁-adrenoceptor agonist) were significantly increased (P< 0.05). Antilipolytic effects of α₂-adrenoceptor and insulin were significantly decreased (P < 0.05). Endurance training in obese men enhances adipose tissue lipolysis through β-adrenergic pathway, and decreases antilipolytic activity.     

Takotsubo cardiomyopathy or transient left ventricular apical ballooning syndrome

Takotsubo is a reversible cardiomyopathy, often triggered by a stressful event. It combines clinical features mimicking a myocardial infarction, transient apical ballooning of the left ventricle, normal coronary arteries and a small rise in troponin level. There is a striking female predominance with mean age ranging from 65 to 76 years among series. Preceding stressful event is documented in 50 to 100% of patients. The most common clinical presentation is an angor-like chest pain with ST-segment elevation on the electrocardiogram (70%). The prognosis is excellent even if serious complications may occur: pulmonary oedema, cardiogenic shock, transient dynamic intraventricular gradient, life-threatening arrhythmias. In-hospital mortality is in the range of 0 to 10%. The recurrence rate is low. The precise physiopathology of the syndrome remains unknown but catecholamine mediated myocardial stunning is the most favored explanation.