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Elevation of plasma glucagon concentration has been observed in starvation and illnesses associated with increased catabolism such as diabetes mellitus and severe infections. Thus, we examined plasma glucose, immunoreactive insulin (IRI, microunits per milliliter) and glucagon (IRG, picograms per milliliter) responses to a beef meal (1 g/kg body wt) and intravenous glucose (1.5 g/min for 45 min) in patients with chronic renal failure (CRF). After the beef meal (n = 6), plasma glucose did not change, IRI rose from 10.1+/-1.2 to 16.3+/-1.1 (P < 0.01), and IRG rose from a fasting value of 225+/-26 to 321+/-40 (P < 0.01) by 90 min (mean+/-SEM). Intravenous infusion of glucose in CRF patients resulted in significant elevations and prolonged disappearance of plasma glucose and insulin when compared to control subjects (P < 0.01). Glucose infusion failed to suppress elevated plasma glucagon concentrations to normal levels.6 wk of chronic hemodialysis in five patients resulted in normal plasma glucose and insulin responses to the same intravenous glucose load. In contrast, plasma glucagon concentration remained unchanged after hemodialysis and there was no correlation of plasma glucagon levels with carbohydrate intolerance.

Argon ions were accelerated to 1.17x10(10) electron volts in the Princeton Particle Accelerator. The synchrotron was tuned by use of a neon beam with a charge-to-mass ratio equal to that of the argon ions. The fully accelerated argon ions were detected by the observation of etched tracks in cellulose nitrate sheets and also by the use of scintillation counters. Predictions of the range and of the characteristics of argon tracks in plastics were confirmed.

Glucose reabsorption was measured in dogs in which sodium reabsorption was stimulated by obstruction of the thoracic inferior vena cava or inhibited by volume expansion with Ringer's lactate. Glucose reabsorption was much higher during periods of enhanced sodium reabsorption than during sodium diuresis. The relationship of glucose reabsorption to glomerular filtration rate was examined using data from animals that had fractional sodium excretion rates of less than 1%. Under this condition the relationship of glucose reabsorption to glomerular filtration rate is highly linear. When points obtained during sodium diuresis (C(Na)/GFR>0.1) are plotted on the same graph, glucose reabsorption at any given glomerular filtration rate is much less than during antidiuresis. Glucose reabsorption divided by glomerular filtration rate varies inversely with fractional sodium excretion. This study demonstrates that glomerular tubular balance for glucose exists in the dog and that this balance is changed when sodium reabsorption changes.

Nitrogen ions in charge states N(5+) and N(6+) have been accelerated in the Princeton Particle Accelerator to 4 and 7.4 billion electron volts (Gev), respectively. An external N(5+) beam of 1 x 10(6) particles per second has been obtained and focused to a 6-millimeter-diameter spot. The N(6+) beam was about 2 x 10(5) particles per second. The total charge-changing collision cross section of N(5+) in water vapor was determined as a function of ion energy. The improvement in vacuum necessary to increase the N(5+) beam at least tenfold was calculated. The N(6+) total cross section is probably smaller than that of N(5+) at the higher energies.