RATIONALE: Maternal deprivation at postnatal day 3 was reported to enhance fear learning in a sex specific manner. Since the amygdala is critically involved in fear conditioning we examined here whether maternal deprivation regulates dendritic complexity in this area. OBJECTIVE: To assess whether maternal deprivation regulates dendritic complexity in the basolateral amygdala of male and female rats. METHODS: Using the Golgi-impregnation method, we studied whether 24 h of maternal deprivation on postnatal day 3 alters dendritic complexity of pyramidal and stellate cells in the basolateral amygdala of adult male and female rats. RESULTS: Maternal deprivation did not affect the total branch length, number of branch points and primary dendrites or dendritic complexity index in male and female offspring. CONCLUSION: Although a brief period of maternal deprivation increases fear conditioned responses, it did not affect dendritic complexity in the basolateral amygdala. This suggests that other cellular substrates for learning and memory, e.g. at synaptic or cellular level, underlie the enhanced expression of fear memories after exposure to early life stress. This article is part of a Special Issue entitled 'Anxiety and Depression'.