Making sense of their surroundings: How the loss of social senses can affect neuropeptide expression dynamics in the brain of zebrafish (Danio rerio)

Abstract

Social interactions, relying on sensory information, are important for the well-being of social animals. Chronic sensory loss can alter neuropeptide activity in the brain, affecting how animals experience social interactions. In zebrafish, thalamic expression of the excitatory parathyroid hormone 2 (Pth2) decreases during social isolation. Furthermore, thalamic pth2 expression overlaps with the inhibitory somatostatin 6.1 (Sst6.1). The dynamics of these neuropeptides and how they change with social sensory loss is not fully explored. I hypothesize that thalamic co-expression of pth2 and sst6.1 display a phenomenon called “transmitter switching” in response to isolation or sensory loss. My findings using manual and genetic sensory loss show that a loss of mechanical lateral line stimuli and vision leads to isolated pth2 levels, while sst6.1 expression also decreases with social isolation and sensory loss. My research also reveals that thalamic pth2- and sst6.1-expressing neurons within a heterogeneous population display a potential switching dynamic.