Abnormalities in neuroendocrine function and sympathetic nervous system activity appear to be present in primary
anorexia nervosa. Hypothalamic
catecholamines are involved in control of endocrine function and
norepinephrine is released from sympathetic nerve endings. Because of possible abnormalities in
catecholamine metabolism, plasma levels of
norepinephrine and urinary excretion of
homovanillic acid and 3-methoxy-4-hydroxyphenyl glycol were studied in female patients with primary
anorexia nervosa before and after significant clinical improvement and compared with normal female volunteers. During the phase of the disease in which
body weights were more than 20--25% below ideal, patients' blood pressures and pulse rates, plasma levels of
norepinephrine, and 24-h urinary excretion of 3-methoxy-4-hydroxyphenol glycol and
homovanillic acid were lower than those of a group of normal volunteers. After
weight gain, these parameters increased to near-normal levels. At no time was plasma
dopamine-beta-hydroxylase activity abnormal. The results suggest that abnormalities in
catecholamine metabolism in primary
anorexia nervosa are caused by
starvation, and that neuronal functions dependent on aminergic neurotransmission may be altered as a result.