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Updated: Aug 10, 2026

Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry
Published on: November 21, 2012
Effects of d-amphetamine on urinary metabolites of dopamine and norepinephrine in hyperactive boys
Abstract:
The authors measured the urinary metabolites 3-methoxy-4-hydroxyphenylglycol (MHPG) and homovanillic acid (HVA) in 21 hyperactive boys and 12 matched healthy boys. The hyperactive boys excreted lower amounts of MHPG than control boys. Hyperactive drug responders excreted lower amounts of HVA than control boys and hyperactive nonresponders. Drug responders with normal MHPG excreted low amounts of HVA and those with normal HVA excreted low amounts of MHPG. d-Amphetamine decreased MHPG in all drug responders and HVA in drug responders with normal HVA levels, although it tended to increase HVA in those with low HVA levels. The authors discuss their data in terms of the possible involvement of norepinephrine and dopamine in the etiology of hyperactivity in children.
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