Microglial peri?somatic abutments classify two novel types of GABAergic neuron in the inferior colliculus

Emerging evidence suggests functional roles for microglia in the healthy, mature nervous system. However, we know little of cellular density and ramified morphology sensory systems, even less their inter-relationship with inhibitory neurons. We therefore conducted fluorescent multi-channel immunohistochemistry confocal microscopy guinea pigs both sexes Iba1, GAD67, GFAP, calbindin, calretinin. explored these markers inferior colliculi (IC), which contain sub-regions specialized different aspects auditory processing. First, found that while Iba1+ somata is similar throughout IC parenchyma, dorsal cortex are significantly more than those central nucleus or lateral cortex. Conversely, ramifications ventral nucleus, a region highest GAD67+ (putative GABAergic) neurons IC, longer fewer ramifications. Second, observed extensive abutments processes onto whole developed novel measures to quantify these. Cluster analyses revealed two sub-types neuron differ quantity somatic they receive. Unlike previous classification schemes clusters not related soma size. Taken together, data demonstrate microglial vary between adult possibly ongoing demands niche. Furthermore, neuronal means by can be classified.