To assess the effect of epidural block on plasma catecholamines and cortisol during labour and delivery, plasma epinephrine, norepinephrine and cortisol levels were determined in 26 healthy parturients, all of whom delivered vaginally (18 received a n epidural block, eight had meperidine 50 mg intramuscularly). We found a significant drop of plasma epinephrine and cortisol and no significant reduction of plasma norepinephrine 1 h after administration of epidural block compared to preblock values. Observing the data during the whole course of labour in correlation with cervical dilatation, in the control group, where the parturients received meperidine, all hormones rose progressively up to the moment of delivery. One hour after delivery the catecholamines returned to normal levels; cortisol returned more slowly. In the epidural group the increase of plasma epinephrine and cortisol was significantly inhibited but not that of norepinephrine.

High-intensity exercise leads to an increased risk of upper respiratory tract infections in athletes, which had been related to an exercise-induced impairment of neutrophil function. In this study, several indices of neutrophil function were analysed before and after a biathlon and the effect of oral vitamin C on neutrophil function was determined. Six athletes took 2 g vitamin C daily for 1 week prior to a biathlon and four athletes did not take any supplementation. Neutrophil phagocytosis was analysed by fluorescence microscopy and flow cytometry. Cytosolic calcium kinetics were assessed fluorometrically and neutrophil bactericidal ability was assessed by fluorescence microscopy. Reactive oxygen production was analysed by flow cytometry. Catecholamines were analysed by high-performance liquid chromatography. After high-intensity exercise there were significant reductions in the number of phagocytosed Escherichia coli per neutrophil and in neutrophil bactericidal ability. There was a significant exercise-dependent increase of catecholamines. There was no difference between the two groups of athletes. These results do not support the concept that vitamin C supplementation corrects neutrophil dysfunction after strenuous exercise.

To assess the effect of epidural block on plasma catecholamines and cortisol during labour and delivery, plasma epinephrine, norepinephrine and cortisol levels were determined in 26 healthy parturients, all of whom delivered vaginally (18 received an epidural block, eight had meperidine 50 mg intramuscularly). We found a significant drop of plasma epinephrine and cortisol and no significant reduction of plasma norepinephrine 1 h after administration of epidural block compared to preblock values. Observing the data during the whole course of labour in correlation with cervical dilatation, in the control group, where the parturients received meperidine, all hormones rose progressively up to the moment of delivery. One hour after delivery the catecholamines returned to normal levels; cortisol returned more slowly. In the epidural group the increase of plasma epinephrine and cortisol was significantly inhibited but not that of norepinephrine.

Rapid gastric emptying and exaggerated plasma concentrations of the insulinotropic hormone GLP-1 precede reactive hypoglycemia after oral glucose in gastrectomy patients. We suspected that the plasma volume drop associated with rapid gastric emptying (early dumping) would be accompanied by elevated plasma concentrations of norepinephrine. In order to study any relationship between postprandial norepinephrine, the enteroinsular axis, and plasma glucose, twelve patients with dumping syndrome and nine controls were studied. The plasma concentrations of norepinephrine, GLP-1, GIP, glucagon, insulin, and glucose were measured following a 1.5 g/kg lean body mass glucose meal. The early (0-30 min) integrated norepinephrine concentration was significantly higher in dumpers (22.1 +/- 3.8 nmol/ml/min) compared to controls (14.7 +/- 3.1 nmol/ml/min; P < 0.001) and correlated closely with the postprandial hematocrit increment (r = 0.71; P < 0.05). Early immunoreactivities of GLP-1, GIP, and glucagon peaked 30 min after glucose ingestion and were significantly higher in dumpers. Insulin peaked after 60 min and correlated with early GLP-1. In 11 of the patients glucose fell below baseline after a median interval of 120 min. Glucose at 120 min, when most of the nadirs occurred was lowest in patients with high early GLP-1 concentrations (r = 0.78; P < 0.001). Gel filtration chromatography of the dumpers' plasma revealed that pancreatic glucagon was detectable at time 0 and after 20 min, but not after 120 min. It is concluded that in dumpers pancreatic glucagon is augmented in the early postprandial period, probably through stimulation by catecholamines. At 120 min, when most of the hypoglycemias are encountered, pancreatic glucagon is no longer detectable, probably through inhibition by GLP-1.

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