TABLE 1

Criteria for defining change in [Ca2+]i in glucose-excited and glucose-inhibited neurons

Cell typeTreatment (mmol/l)Latency (min; means ± SD)Standard latency (min; means ± 1.5 SD)Percentage change in [Ca2+]i AUC (mean % ± SD)Minimum change in [Ca2+]i AUC (mean % − 1.5 SD)
Glucose-excited neurons2.5 G→0.5 G1.8 ± 1.64.256 ± 24↓20%↓
0.5 G→2.5 G2.9 ± 1.85.663 ± 20↑33%↑
2.5 G→+4 alloxan2.9 ± 2.05.958 ± 26↓20%↓
Glucose-inhibited neurons2.5 G→0.5 G2.8 ± 2.36.379 ± 13↑59%↑
0.5 G→2.5 G2.8 ± 2.26.175 ± 19↓46%↓
2.5 G→+4 alloxan2.8 ± 2.05.873 ± 17↑47%↑
  • Dissociated VMN neurons from 14- to 21-day-old rat pups were subjected to changing glucose (G) concentrations from 2.5 to 0.5 or 0.5 to 2.5 mmol/l in the presence or absence of 4 mmol/l alloxan. Latencies and changes in [Ca2+]i responses (AUC) were determined from the Ca2+ traces of a total of 108 individual glucose-excited or -inhibited and nonglucosensing neurons as described in research design and methods and illustrated in Fig. 1. Direction of arrows indicates decreased (↓) or increased (↑) [Ca2+]i.