Exogenous hyperglucagonaemia in insulin controlled diabetic rats increases urea excretion and nitrogen loss from...

In order to study the effect of hyperglucagonaemia on nitrogen metabolism in diabetes, zinc protamine glucagon 60 micrograms was injected subcutaneously 3 times daily for 4 weeks into streptozotocin diabetic rats (n = 5), adequately treated with long acting insulin. This raised the plasma concentration of glucagon to 725 +/- 125 (mean +/- SEM), which is not different from that found in portal blood of uncontrolled diabetic rats: 400 +/- 75 ng/l. The controls were 5 diabetic rats treated with insulin alone and 5 non-diabetic rats. Compared with control rats the nitrogen balance was reduced (p less than 0.05) and the nitrogen contents of carcass, heart, intestines, and kidneys were reduced by 15-30% (p less than 0.05) in the glucagon treated rats. The hepatic capacity of urea synthesis and the alanine elimination rate were determined in the 3 above-mentioned groups, and confirmed in 3 identical groups followed for only 2 weeks; and in addition in a group of glucagon treated diabetic rats, where the long acting glucagon was substituted by neutral insulin the last two days before investigation.(ABSTRACT TRUNCATED AT 250 WORDS)