Fig. 2.

Long-term, sustained delivery of GDNF and resulting elevation tissue levels of GDNF within the implanted striatum. Fig. 2a demonstrates that GDNF device secretion peaks early post implantation but then stabilizes and remains consistent for at least 6 months in vivo. Fig. 2b confirms that GDNF delivery results in sustained tissue levels within the implanted striatum. When explanted from the striatum the output of the devices over time generally paralleled the enhanced tissue concentrations with an early peak in delivery followed by a longer, sustained output similar to that noted from the same devices immediately prior to implantation. All data are expressed as mean ​± ​SEM of 4 animals each with bilateral implants per time-point. BLQ ​= ​below limit of quantitation.