Environmental stimuli but not homeostatic challenges produce apparent increases in dopaminergic activity in the striatum: an analysis by in vivo voltammetry.

摘要: Using in vivo voltammetry rats, we examined the relationship between electrochemical signal measured striatum and behavioral responses associated with various type of stimulation. Three patterns emerged. First, a series homeostatic challenges, including abrupt decreases glucose utilization, blood volume, or arterial pressure, were ineffective altering despite sympathoadrenal response produced by each. Second, intense exteroceptive stimuli, such as an electric shock applied to tail placing animals shallow ice-water bath, provoked large rises which decayed rapidly. Third, rats eating after 24-h fast, drinking period dehydration, presented novel olfactory visual exhibited much smaller more gradual long-lasting. In each case, magnitude change was generally related level activation, being most prominent when treatments startle response. Those increases markedly attenuated pretreatment withα-methyl-p-tyrosine γ-butyrolactone, drugs known decrease release dopamine, suggesting that observed increase activity central dopaminergic neurons.