Intraventricular injection of neostigmine increases dopaminergic and noradrenergic nerve activities: hyperglycemic effects and neurotransmitters in the hypothalamus.

The contents of hypothalamic neurotransmitters were examined under inducement of hyperglycemia by intraventricular administration of neostigmine, after pretreatment with microwave irradiation. Extracellular levels of the metabolites of these neurotransmitters were also measured using in vivo microdialysis. Our data suggest that neostigmine affects not only the cholinergic system but also the noradrenergic and dopaminergic systems in the hypothalamus. In order to clarify the relationship between excitement or regulation of physiological events and activities of central specific neurons, we therefore suggest that studies by chemical stimulation are insufficient on their own; it is also necessary to measure fluctuations both in neurotransmitter content and in extracellular levels of their metabolites.