Effect of insulin on the exaggerated glucagon response to arginine stimulation in diabetes mellitus

The effect of insulin on the glucagon response to intravenous arginine was studied in 8 juvenile type and 6 adult onset diabetics. In the juvenile type diabetics, concomitant administration of insulin significantly blunted the glucagon response from a mean maximal rise of 310 ± 54 pg/ml to only 184 ± 39 pg/ml (p<0.01), about the same as in nondiabetics. In the adult onset patients, however, insulin had no effect, the mean maximal rise being 250 ± 50 pg/ml without insulin and 307 ± 71 pg/ml with insulin (N.S.). This study demonstrates that in juvenile type diabetes concomitant administration of supraphysiologic quantities of insulin can reduce the exaggerated glucagon response to intravenous arginine to normal, whereas in the adult type group, it has no apparent effect.