Integrating Immunostaining with Tissue Clearing Techniques for Whole Brain Mapping in Basal Ganglia and Drug Addiction

Abstract

Summary form only given. Traditional immunostaining techniques utilize antibodies to probe the expression of specific proteins in the brain, but this only allows for two-dimensional mapping that cannot recapitulate the complex circuit and regional interactions that occur in the brain. To achieve a more advanced level of circuitry mapping, we combine classic immunofluorescence staining with a tissue clearing technique, immunolabelling-enabled three-dimensional imaging of solvent-cleared organs (iDISCO), to map neurocircuits in the intact brain. Coupling these technologies permits analysis of neuronal circuits under a variety of conditions, including responses to visual and auditory stimuli, as well as in response to pharmacological agents or drugs of abuse. We apply these technologies to study the neuronal activity changes in the basal ganglia driven by selective dopamine-D1 receptor agonist 2-chloro-APB hydrobromide in wild type and Slc35d3 heterozygous mice and correlated behavioral changes with differences in circuit response. We also map tyrosine hydroxylase positive projection neurons in the whole brains of methamphetamine-injected rats. Based on these studies, we can target specific neuronal populations stimulated in response to these compounds to modulate circuit activation as a potential intervention in basal ganglia function and in drug abuse.