Abnormal oesophageal function in patients with non-toxic goiter or enlarged left atrium, demonstrated by radionuclide transit measurements.

In 10 patients with enlarged atrium and in 29 patients with goiters and neck discomfort dynamic oesophageal scintigraphy was performed. The passage of water and capsules, containing 99mTc-pertechnetate, was studied with the patients in the supine and in the sitting positions. As a reference group we examined 35 healthy, age-matched volunteers. Mean transit time (MTT) was calculated, residual activity was expressed as a percentage of maximum activity, and the number of spikes in the curves was defined by visual analysis. Both in patients with enlarged left atrium and in those with large goiters the studies showed significantly prolonged MTT, increased residual activity, and a higher frequency of spikes, compared with healthy volunteers and with patients with small goiters. There was no relationship between symptoms and abnormal scintigraphic results. The passage of capsules was impaired only in cardiac patients. It is concluded that abnormal oesophageal function is often present in patients with enlarged left atrium and in patients with large, but not with small, goiters. Inhibition of oesophageal transit appears to be dependent on mechanical compression, but the nature of oesophageal impairment may vary with the level of compression. The frequent complaints of neck sensations in patients with goiters are probably not of oesophageal origin.

Kinetics of insulin disappearance from plasma in cortisone-treated normal subjects.

The effect of glucocorticoid excess on insulin disappearance from plasma was examined in eight normal men during cortisone treatment (50 mg orally twice daily for 4 d) and in the absence of any medication (control) in random order. Constant infusion of insulin (1-5 mU/kg/min) was used to achieve different levels of steady state plasma insulin concentrations; normoglycaemia was preserved by a glucose clamp technique. The experimentally determined data were compared using a previously validated model of saturation kinetics. The amount of glucose required to maintain normoglycaemia during the insulin infusions was significantly less in the cortisone study than in the control study, while the parameter estimates for the kinetics of insulin disappearance from plasma were unaffected by cortisone. Thus, insulin action and insulin kinetics in the steady state are dissociated in normal subjects rendered insulin resistant by short-term cortisone treatment.