Local Infusion of Insulin Restores AMPH-Evoked DA Release in Striatum of STZ-Treated Rats

<p>Summary data for HSCA (<i>n</i> = 5–7). When measured in the dorsal striatum and compared to saline-treated control subjects, STZ-induced depletion of insulin (STZ) resulted in a significant reduction in the rate of DA efflux in response to local injection of AMPH (400 μM/125 nl; (A) as well as a decrease in the maximum amount of released DA (B) and the rate of DA clearance (C) with respect to control. These findings provide a replication of those shown in <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0050274#pbio-0050274-g002" target="_blank">Figure 2</a> in a separate cohort of rats. In contrast, when exogenous insulin (10 μM/100 nl) is locally applied in STZ animals 2 min prior to AMPH (STZ+Ins), all three of these electrochemical parameters are normalized to levels approximating control. One-way ANOVA (<i>F</i>_2,14 = 2.46; <i>p</i> < 0.05); Mann-Whitney (<i>p</i> < 0.05 compared to Control* and STZ+Ins#).