AIMS/HYPOTHESIS: Our hypothesis is that reducing release of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) with modafinil will enhance symptomatic and hormonal responses to hypoglycaemia. METHODS:Nine healthy men received, in random order, two 100-mg doses of modafinil or placebo, followed by an insulin clamp in which plasma glucose was either reduced stepwise to 2.4 mmol/l or was sustained at euglycaemia (four studies). Catecholamines, symptom scores and cognitive function were measured. RESULTS:Modafinil had no effect on the measured parameters during euglycaemia. During hypoglycaemia, autonomic symptom scores were significantly higher with modafinil (increase at lowest plasma glucose concentration 271.3+/-118.9 vs 211.2+/-80.4/40 min, p=0.019), and the heart rate response was increased (12,928+/-184 vs 6773+/-148 bpm/140 min, p=0.016). Deterioration in performance of two cognitive tasks was reduced: Stroop colour-word test (613+/-204 vs 2375+/-161/65 min, p=0.009) and accuracy of a simple reaction task (11.3+/-1.8 vs 9.4+/-3.7, p=0.039). CONCLUSIONS/ INTERPRETATION: We conclude that modafinil improves adrenergic sensitivity and some aspects of cognitive function at hypoglycaemia, possibly by reducing neuronal central GABA concentrations.
RCT Entities:
AIMS/HYPOTHESIS: Our hypothesis is that reducing release of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) with modafinil will enhance symptomatic and hormonal responses to hypoglycaemia. METHODS: Nine healthy men received, in random order, two 100-mg doses of modafinil or placebo, followed by an insulin clamp in which plasma glucose was either reduced stepwise to 2.4 mmol/l or was sustained at euglycaemia (four studies). Catecholamines, symptom scores and cognitive function were measured. RESULTS:Modafinil had no effect on the measured parameters during euglycaemia. During hypoglycaemia, autonomic symptom scores were significantly higher with modafinil (increase at lowest plasma glucose concentration 271.3+/-118.9 vs 211.2+/-80.4/40 min, p=0.019), and the heart rate response was increased (12,928+/-184 vs 6773+/-148 bpm/140 min, p=0.016). Deterioration in performance of two cognitive tasks was reduced: Stroop colour-word test (613+/-204 vs 2375+/-161/65 min, p=0.009) and accuracy of a simple reaction task (11.3+/-1.8 vs 9.4+/-3.7, p=0.039). CONCLUSIONS/ INTERPRETATION: We conclude that modafinil improves adrenergic sensitivity and some aspects of cognitive function at hypoglycaemia, possibly by reducing neuronal central GABA concentrations.
Authors: Linda Scoriels; Jennifer H Barnett; Praveen K Soma; Barbara J Sahakian; Peter B Jones Journal: Psychopharmacology (Berl) Date: 2011-09-10 Impact factor: 4.530
Authors: Maka S Hedrington; Stephnie Farmerie; Andrew C Ertl; Zhihui Wang; Donna B Tate; Stephen N Davis Journal: Diabetes Date: 2010-01-19 Impact factor: 9.461