The authors examined urinary levels of catecholamines and metabolites
during a 10-day period of heroin use in 9 subjects. Catecholamine and
metabolite excretion increased over baseline values on the first day of
heroin use, but markedly different patterns of change emerged later. In
contrast to the significant increase in normetanephrine and decrease in
metanephrine excretion in all 9 subjects during heroin use, only 4 subjects
showed an increase in 3-methoxy-4-hydroxyphenyl glycol (MHPG) excretion.
Moreover, it appeared that the increase in MHPG excretion in this subgroup
began on the day before heroin administration, which suggests the
possibility of an anticipatory or conditioned response.Abstract Teaser