Brain Structure and Function

, Volume 213, Issue 1, pp 149–157

Automated quantification of dendritic spine density and spine head diameter in medium spiny neurons of the nucleus accumbens

  • Haowei Shen
  • Susan R. Sesack
  • Shigenobu Toda
  • Peter W. Kalivas
Original Article

DOI: 10.1007/s00429-008-0184-2

Cite this article as:
Shen, H., Sesack, S.R., Toda, S. et al. Brain Struct Funct (2008) 213: 149. doi:10.1007/s00429-008-0184-2

Abstract

Dendritic spines are postsynaptic specializations thought to regulate the strength of synaptic transmission and play a critical role in neuronal plasticity. While changes in dendritic spine density can be pharmacologically- or environmentally-induced, the widespread utility of this important measure of synaptic plasticity in vivo has been hampered by the labor-intensive nature, and potential for bias and inconsistency inherent in manual spine counting. Here we report a method for obtaining high-resolution, three-dimensional confocal images of accumbens spiny neurons labeled with a diolistically delivered lipophilic fluorescence dye (DiI) that permits automated analysis of spine density and spine head diameter. The automated quantification was verified by manual counts of spine density and electron microscopic measures of spine head diameter. The density of spines was relatively constant over 2nd to 4th order dendrites within a neuron, and spine density was normally distributed. The mean spine density (2.68 spines/μm; N = 45 neurons) was higher than previous reports, due in part to analysis in three rather than two dimensions and the capacity of lipophilic dyes to fill very thin spines. The distribution of spine head diameters was continuous and skewed to the right (mean = 0.43 μm; N = 8,891), and ~25% of all spines were thin and filopodia-like (≤0.20 μm diameter). The density of spines was not correlated with average spine head diameter or with the number of filopodia-like spines. The capacity to rapidly assess spine density and spine head diameter will facilitate quantifying spine plasticity induced by pharmacological and environmental manipulations.

Keywords

Nucleus accumbens Spiny neuron Dendrite Dendritic spine Diolistic labeling 

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Haowei Shen
    • 1
  • Susan R. Sesack
    • 2
  • Shigenobu Toda
    • 1
  • Peter W. Kalivas
    • 1
  1. 1.Department of NeurosciencesMedical University of South CarolinaCharlestonUSA
  2. 2.Departments of Neuroscience and PsychiatryUniversity of PittsburghPittsburghUSA