Early lesion of mystacial vibrissae in rats results in an increase of somatostatin-labelled cells in the somatosensory cortex.

Recent studies in the developing cortex have shown that during the first 2 postnatal weeks somatostatin (SRIF)-containing neurons appear in greater numbers. After this time their numbers decline significantly probably due to cell death (Cavanagh and Parnavelas 1988). In this study we report changes in the distribution of SRIF-labelled cells in the somatosensory cortex of adult rats following unilateral lesions of mystacial vibrissae at birth. Specifically, we observed that the side contralateral to the lesion contained a significantly greater number of labelled cells compared to the ipsilateral side. We suggest that the decline in cell numbers observed during normal development is reduced following early deafferentation.