TABLE 1

Mean ± SE plasma epinephrine, norepinephrine, pancreatic polypeptide, growth hormone, and cortisol concentrations during low-dose stepped hyperinsulinemic euglycemic clamps (Eu), stepped hypoglycemic (4.7, 4.2, 3.6, and 3.0 mmol/l) clamps (Hypo), and stepped hypoglycemic clamps with tolbutamide 1.0 g/h (Hypo + Tolb) from 60 to 300 min*

Time (min)
P
−15060120180240300
Epinephrine (pmol/l)
 Eu130 ± 40120 ± 3595 ± 10115 ± 15130 ± 20130 ± 15145 ± 20
 Hypo85 ± 10110 ± 2085 ± 10100 ± 15145 ± 20670 ± 1901,500 ± 315
 Hypo + Tolb85 ± 1075 ± 1075 ± 1080 ± 10135 ± 10790 ± 2651,560 ± 2500.8956
Norepinephrine (nmol/l)
 Eu0.85 ± 0.090.77 ± 0.090.77 ± 0.120.84 ± 0.120.90 ± 0.150.93 ± 0.100.87 ± 0.08
 Hypo0.87 ± 0.120.74 ± 0.250.72 ± 0.090.82 ± 0.120.88 ± 0.120.96 ± 0.111.16 ± 0.15
 Hypo + Tolb0.87 ± 0.080.85 ± 0.100.95 ± 0.050.87 ± 0.090.93 ± 0.120.97 ± 0.111.16 ± 0.120.9537
Pancreatic polypeptide (pmol/l)
 Eu16 ± 416 ± 424 ± 1315 ± 413 ± 312 ± 214 ± 4
 Hypo25 ± 519 ± 419 ± 618 ± 416 ± 337 ± 1078 ± 18
 Hypo + Tolb30 ± 827 ± 528 ± 819 ± 324 ± 550 ± 12139 ± 160.0037
Growth hormone (pmol/l)
 Eu53 ± 1862 ± 2235 ± 1944 ± 18194 ± 66106 ± 4475 ± 26
 Hypo62 ± 3149 ± 1835 ± 1326 ± 449 ± 18362 ± 115340 ± 88
 Hypo + Tolb84 ± 3571 ± 2626 ± 035 ± 953 ± 31128 ± 44402 ± 1190.1324
Cortisol (nmol/l)
 Eu510 ± 45495 ± 60380 ± 55355 ± 45330 ± 40260 ± 25235 ± 25
 Hypo435 ± 60410 ± 60315 ± 50305 ± 40255 ± 35355 ± 50420 ± 50
 Hypo + Tolb430 ± 55390 ± 55335 ± 50330 ± 45275 ± 35255 ± 35410 ± 350.0386
  • *

    * To convert epinephrine to pg/ml, divide by 5.458; norepinephrine to pg/ml, divide by 0.005911; pancreatic polypeptide to pg/ml, divide by 0.239; growth hormone to ng/ml, divide by 44.15; cortisol to μg/l, divide by 27.59.

  • Hypo versus Hypo + Tolb.