Lifelong reversal of the metabolic abnormalities of advanced diabetes in rats by whole-pancreas transplantation

Evidence suggests that metabolic abnormalities are responsible for the widespread microvascular complications of insulin-dependent diabetes mellitus (IDDM). Interest in endocrine pancreas replacement therapy, including pancreas transplantation, is based on the hope that such treatment will reverse the complications of IDDM by providing more precise metabolic control than conventional therapy. To determine if whole pancreas transplantation is capable of reversing well-established metabolic abnormalities of diabetes mellitus (DM) and maintaining strict metabolic control for life, we performed monthly metabolic studies for 2 years in 141 nondiabetic control rats, 273 diabetic control rats with alloxan-induced DM, and 267 diabetic rats that received syngeneic whole pancreaticoduodenal transplants 6, 9, 12, 15, 18, and 21 months after induction of DM with alloxan. Whole-pancreas transplantation in rats with long-standing DM permanently reversed the metabolic disorders. Elevated plasma glucose concentrations were permanently reduced to normal, depressed plasma insulin levels were permanently increased to normal, elevations of BUN and serum creatinine were permanently normalized, and there was a striking gain in body weight. Hyperglycemia during glucose tolerance tests was of lesser magnitude and shorter duration than normal, as a result of greater-than-normal plasma insulin levels. The only abnormality that persisted was hyperglucagonemia, but it did not interfere with control of hyperglycemia and is of unknown significance. These results indicate that whole-pancreas transplantation produces the most complete and sustained correction of the metabolic abnormalities of experimental DM of any available therapeutic modality.

Repeat surgery after disc excision

Sixty patients requiring repeat surgery after lumbar disc excision are reviewed. Thirty-one had had their initial surgery performed by the authors and represent a 5.9% frequency of repeat surgery after initial laminectomy for sciatica. Of the 60 patients, 49 suffered recurrent radicular pain, 20 suffered from back pain, and 8 had other problems (infection, extradural cysts, etc.). In patients with recurrent sciatica, perineural fibrosis and recurrent herniation were the most common problems; those patients with the latter pathologic condition responded most favorably to repeat surgery. Of 520 patients who had undergone disc excision, only 9 required secondary fusion.

Autonomic nervous system and adaptation to cold in man

The responses to cold hand test (blood pressure increase and tachycardia) and to a cold face test (blood pressure increase and bradycardia) were used to study the role of the autonomic nevrous system in cold adaptation in humans. The Eskimos (men, women, children) were shown to have a very weak sympathetic response to cold but the vagal response (bradycardia) was identical to that of white people. A group of mailmen from Quebec city living outdoors approximately 30 h/wk throughout the year was also studied. A significant decline in the cold pressor response and an enhanced bradycardia (cold face test) were observed at the end of the winter. Similarly the fall in skin temperature of the cheek was not as pronounced when the measurements were made in May compared to those made in October. A group of soldiers was also studied before and after an Arctic expedition. It was found that the bradycardia of the cold face test was also more pronounced after sojourning in the cold. These results indicate that repeated exposures to severe cold in men activate some adaptive mechanisms characterized by a diminution of the sympathetic response and a concomitant enhancement of the vagal activation normally observed when the extremities and the face are exposed to cold.