Distribution of tyrosine hydroxylase-expressing interneurons with respect to anatomical organization of the neostriatum

Creative Commons License

Ünal B., Ibáñez-Sandoval O., Shah F., Abercrombie E. D., Tepper J. M.

Frontiers in Systems Neuroscience, vol.5, no.JUNE 2011, 2011 (Scopus) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 5 Issue: JUNE 2011
  • Publication Date: 2011
  • Doi Number: 10.3389/fnsys.2011.00041
  • Journal Name: Frontiers in Systems Neuroscience
  • Journal Indexes: Scopus
  • Keywords: GABAergic, striatum, striosome, matrix, dopamine island
  • TED University Affiliated: No


We have recently shown in vitro that striatal tyrosine hydroxylase-expressing interneurons identified in transgenic mice by expression of enhanced green fluorescent protein (TH-eGFP) display electrophysiological profiles that are distinct from those of other striatal interneurons. Furthermore, striatal TH-eGFP interneurons show marked diversity in their electrophysiological properties and have been divided into four distinct subtypes. One question that arises from these observations is whether striatal TH-eGFP interneurons are distributed randomly, or obey some sort of organizational plan as has been shown to be the case with other striatal interneurons. An understanding of the striatal TH-eGFP interneuronal patterning is a vital step in understanding the role of these neurons in striatal functioning. Therefore, in the present set of studies the location of electrophysiologically identified striatal TH-eGFP interneurons was mapped. In addition, the distribution of TH-eGFP interneurons with respect to the striatal striosome-matrix compartmental organization was determined using μ-opioid receptor (MOR) immunofluorescence or intrinsic TH-eGFP fluorescence to delineate striosome and matrix compartments. Overall, the distribution of the different TH-eGFP interneuronal subtypes did not differ in dorsal versus ventral striatum. However, striatal TH-eGFP interneurons were found to be mostly in the matrix in the dorsal striatum whereas a significantly higher proportion of these neurons was located in MOR-enriched domains of the ventral striatum. Further, the majority of striatal TH-eGFP interneurons was found to be located within 100 μm of a striosome-matrix boundary. Taken together, the current results suggest that TH-eGFP interneurons obey different organizational principles in dorsal versus ventral striatum, and may play a role in communication between striatal striosome and matrix compartments. © 2011 Ünal, Ibáñez-Sandoval, Shah, Abercrombie and Tepper.