Key result
Both adenosine and insulin significantly increased glucose uptake compared with control (0.34 and 0.44 vs 0.23 mumol/min/g; P<0.05), with an additive effect when combined (0.54 mumol/min/g).
Absolute Event Rate: 0.54% vs 0.23%
p-value: p=< 0.05
Adenosine and insulin increase myocardial glucose uptake in normoxic rat hearts through distinct mechanisms, as demonstrated by their additive effects and differential sensitivity to the inhibitor phloridzin.
Should not change clinical glucose modulation in humans; leaves open translation of additive effects from rat models.
The effect of adenosine (ADO) and its interaction with insulin (I) on myocardial glucose uptake was evaluated in the normoxic isolated rat heart using 2-[3H]deoxyglucose. Isovolumic hearts were perfused at constant flow with a nonrecirculating bicarbonate buffer containing 5.5 mM glucose as the sole substrate. After a 30-min equilibration period, the glucose and extracellular ([14C]sucrose) tracers were infused for 15 min before initiation of the 15-min experimental period. Both 100 microM ADO and 4 mU/ml I significantly increased glucose uptake (GU) compared with control values (in mumol.min-1 x g-1: ADO = 0.34 +/- 0.03, I = 0.44 +/- 0.03, control = 0.23 +/- 0.02; P < 0.05). In combination, ADO and I produced an additive increase in GU (0.54 +/- 0.03; P < 0.05 vs. control). The mechanism of enhanced GU by ADO and I was investigated with the glucose uptake inhibitors phloridzin (PZ) and phloretin (PT), each of which has a unique site of action on the cell membrane. ADO-mediated GU was completely blocked by 3 mM PZ (ADO + PZ = 0.20 +/- 0.01; P = NS vs. control), but I-stimulated GU was unaffected (I + PZ = 0.38 +/- 0.03; P = NS vs. I). Only GU attributable to ADO was blocked by PZ infused with ADO and I (ADO + I + PZ = 0.43 +/- 0.03; P = NS vs. I). Both ADO- and I-mediated GU were inhibited by 100 microM PT.(ABSTRACT TRUNCATED AT 250 WORDS)
No takes yet. Share an insight, caveat, or question.
Angello et al. (1993) studied normoxic isolated rat heart. Adenosine and Insulin vs. control was evaluated on glucose uptake (mumol.min-1 x g-1) (p=< 0.05). Both adenosine and insulin significantly increased glucose uptake compared with control (0.34 and 0.44 vs 0.23 mumol/min/g; P<0.05), with an additive effect when combined (0.54 mumol/min/g).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: