engleski

Specific laminar distribution of perineuronal nets in the human anterior cingulate cortex

Recent research found that understanding alterations of the brain extracellular matrix (ECM) is crucial for determining the pathophysiological processes occurring after hypoxic brain injury. Perineuronal nets (PNNs), a form of condensed ECM, are of particular interest in the adult brain. In this study we analyzed the anterior cingulate cortex (ACC) from three adult human brains using double labelling immunofluorescence. The ECM marker Wisteria floribunda agglutinin (WFA) was combined with the neuronal nuclear antigen (NeuN) and four interneuron markers – parvalbumin (PV), calretinin (CR), calbindin (CB) and somatostatin (SOM). NeuN/WFA double labelled slides were quantified using Neurolucida software. Qualitative analysis revealed that WFA+ condensed ECM was present around NeuN+ cells, confirming that these were indeed PNNs. Furthermore, PNNs were found surrounding certain pyramidal and PV+ cells, but not surrounding CR+, CB+ or SOM+ cells. Quantitative analysis revealed that 6.17% ± 0.67% of NeuN+ cells had WFA+ PNNs. PNNs were most abundant in layer III (10.94%), followed by layers V (5.07%) and VI (4.78%). Faintly stained PNNs were found in the superficial white matter (7.11%). PNNs were only sporadically found in layer II and were never present in layer I. In conclusion, PNNs in the human ACC have a specific laminar distribution and are predominantly found surrounding certain pyramidal cells and PV+ interneurons. This has important implications for the functional and laminar organization of the microcircuitry in the human brain, which is critical for understanding the underlying pathophysiology of hypoxic brain injury as well as of disorders such as schizophrenia and bipolar disorder.

extracellular matrix ; perineuronal nets ; GABAergic neurons ; interneurons ; anterior cingulate cortex

nije evidentirano