EFFECTS OF CATECHOLAMINE DEPLETION ON ALERTNESS AND MOOD IN RESTED AND SLEEP-DEPRIVED NORMAL VOLUNTEERS

Alpha-methyl-para-tyrosine (AMPT), a tyrosine hydroxylase inhibitor, w as used to evaluate the physiologic role of central nervous system cat echolamines in modulating alertness and mood. Forty healthy males were randomized to one of four conditions: AMPT in a rested condition; AMP T plus 40.5 hours of total sleep deprivation; placebo plus sleep depri vation; or placebo in a rested condition. Repeated measures of alertne ss and mood revealed that treatment with AMPT or sleep deprivation inc reased sleepiness, and combined treatment produced greater sleepiness than either treatment alone. In contrast, although combined treatment with AMPT and sleep deprivation led to large increases in negative moo d, neither treatment alone produced consistent mood changes. These fin dings are consistent with the view that sleep deprivation is associate d with decreased functional catecholamine neurotransmission. Furthermo re, mood effects following sleep deprivation plus AMPT suggest that ca techolamines may be involved in mood changes during sleep deprivation.