CARBOHYDRATE METABOLISM IN NEPHRITIS

RENAL EFFECTS OF HEMOGLOBIN INFUSIONS IN DOGS IN HEMORRHAGIC SHOCK

The immediate effects of treating hemorrhagic shock in dogs by replacing lost blood with 7 per cent hemoglobin solution were favorable, both on renal function and on general condition. However, subsequent transitory depression of the urea clearance for several days, shown by some of the treated animals, but not by untreated bled controls, indicates sufficient possibility of renal damage by the hemoglobin solution to prevent its recommendation at present as a blood substitute.

Aspects of glucose homeostasis in uremia as assessed by the hyperinsulinemic euglycemic clamp technique

A three-step hyperinsulinemic euglycemic clamp was performed in 14 nondialyzed uremic and ten age-matched healthy subjects. Nine of the uremics were restudied for a mean of 42 days (range, 21 to 88 days) after initiation of dialysis therapy. Insulin was infused at the following three rates: 0.5 mU X kg-1 X min-1, 2.0 mU X kg-1 X min-1, and 4.0 mU X kg-1 X min-1. Each dose was given for 120 minutes. Glucose uptake during the last 30 minutes of each clamp were consistently lower in uremic patients pre-dialysis than in controls (2.3 +/- 0.3 v 6.6 +/- 0.8 mg X kg-1 X min, 7.8 +/- 0.6 v 13.2 +/- 1.1 mg X kg-1 X min-1 and 9.6 +/- 0.7 v 15.5 +/- 1.0 mg X kg-1 X min-1, all P less than 0.001). Serum insulin levels were similar in the two groups, and blood glucose values during steady state were maintained at 79 +/- 2.77 +/- 2, and 77 +/- 2 mg/100 mL in uremic subjects and at 72 +/- 3, 73 +/- 2, and 75 +/- 2 mg/100 mL in healthy subjects. The insulin levels required to elicit half-maximal biological response in uremics (82 +/- 5 microU/mL) were markedly higher than in controls (54 +/- 8 microU/mL, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Glycaemic control in diabetic nephropathy

To investigate the quality of glycaemic control that is achievable in diabetic patients with persistent proteinuria and asymptomatic but declining renal function three matched groups of patients were studied. The first comprised diabetics with proteinuria receiving continuous subcutaneous insulin infusion; the second, diabetics without proteinuria receiving continuous subcutaneous insulin infusion; and the third, diabetics with proteinuria receiving conventional insulin treatment. Glycaemic control in patients receiving continuous subcutaneous insulin infusion was shown to be appreciably worse during the daytime in diabetics with proteinuria than in diabetics without proteinuria, although greatly superior to that in diabetics with proteinuria receiving conventional insulin treatment. The loss of glycaemic control in patients with proteinuria receiving continuous subcutaneous insulin infusion probably occurred as a response to daytime hypoglycaemia and a consequent reduction in the proportion of the total insulin dose given prandially. Difficulty in controlling blood glucose concentrations may be a factor in the failure of intensified insulin regimens to influence the progression of diabetic renal disease.

Metabolism of insulin in erythrocytes from renal failure patients on maintenance hemodialysis

Glucose tolerance does not improve to the normal level after dialysis; however, our studies showed that the insulin receptor binding to erythrocytes of nondiabetic patients with chronic renal failure (CRF) on hemodialysis was more than that in normal subjects. To understand this apparent anomaly in insulin receptor action and glucose metabolism, we investigated insulin degradation-a postreceptor event of insulin binding-in erythrocytes from CRF patients and compared it with that of normal subjects. We studied insulin degradation by erythrocytes from each of eight CRF patients and five normal subjects. The average hyperbolic insulin degradation curve for the CRF patients showed lower activity and a right-handed shift compared to the curve for the normal subjects. The average maximum degradation of insulin in the CRF patients was significantly lower than that of normal subjects. The number of erythrocytes required to produce 50% of maximum insulin degradation was significantly greater in these patients than that in the normal subjects. Furthermore, a linear correlation was observed between the duration of dialysis and maximum percent of insulin degradation in the CRF patients. Clinical implications of these findings are unclear at the present time. However, the insulin-degrading activity in erythrocytes may be reflective of that in other body tissues.

Plasma adenosine 3':5'--cyclic monophosphate response to glucagon in uremia

The effect of a single, intravenously administered dose of glucagon on plasma cyclic adenoside monophosphate (cAMP) was studied in seven normal subjects, ten patients with chronic renal failure (CRF), and ten patients with terminal renal insufficiency (TRI) receiving long-term haemodialysis treatment (HD). Ten minutes following glucagon administration, uremic patients displayed a significantly (P less than 0.0001) greater increase in cAMP than control subjects. Glucose levels after glucagon administration did not differ significantly between the normal and uremic groups, and lipolysis was less pronounced in the uremic patients than in the controls (P less than 0.003). These results could not be attributed to differences in serum insulin response. The findings demonstrate differences in the hepatic adenylate cyclase and cAMP response between normal and uremic subjects. These alterations in cAMP responsiveness may play a role in the pathophysiology of the metabolic disturbances associated with uremia.

Pattern of growth hormone response to insulin, arginine and haemodialysis in uraemic children

Plasma growth hormone (GH) concentrations after insulin and arginine stimulation were estimated in 11 dialyzed and 6 non-dialyzed children with chronic renal failure. Twenty healthy children served as controls. Plasma GH peak concentration and estimation of the total area under the plasma GH concentration-time curve by the trapezoidal rule were used to evaluate results. Elevated basal GH levels and an exaggerated response to the stimuli were seen in several of the patients. The causes of the abnormal GH secretion and the role of high GH levels in carbohydrate intolerance are discussed. No consistent pattern was seen in GH secretion during haemodialysis without glucose in the dialysate. In children undergoing haemodialysis with a fluid containing glucose, plasma GH fell considerably.

Factors in the differential rate of arteriosclerosis (AS) between long surviving renal transplant recipients and dialysis patients

In this study, the incidence of clinical and autopsy arteriosclerosis (AS) was studied in over 300 renal transplant patients (RTP) followed in our clinic up to 13 years post-transplant. Of 45 RTP followed a mean of 10.45 years, the incidence of clinical AS was 6% or 0.58% per year at risk. The incidence of death from AS was 2.2% over 10 years or 0.22% per year at risk. There was no apparent tendency for increase of the risk incidence with increasing time post-transplantation up to 13 years. This incidence of clinical and death-related AS in long term RTP contrasts sharply with a quite high incidence of both clinical and death-related AS in long-term dialysis patients as reported by Scribner's group and both the European and U.S. Dialysis Registry. Of our RTP surviving a decade or more, 77% have normal serum triglycerides and 92% are normotensive, again contrasting sharply with a 70-80% incidence of hyperlipidemia and a 60-80% incidence of hypertension in long-term dialysis patients. These studies suggest that the high rate of accelerated AS in dialysis patients is largely reversed by successful renal transplantation, probably due to a lowering of both blood pressure and hyperlipidemia in the long-term RT patients. Practically, these results suggest that the superior survival of transplant patients over dialysis patients already evident at 10 year mark will widen further during the second post-transplantation decade.

Renal dwarfism: A Record of Abnormalities in Carbohydrate Metabolism

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A Clinical, Pathological and Biochemical Study of Amyloid Nephrosis

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