Central Control Circuit for Context-Dependent Micturition.

Urine release (micturition) serves an essential physiological function as well as a critical role in social communication in many animals. Here, we show a combined effect of olfaction and social hierarchy on micturition patterns in adult male mice, confirming the existence of a micturition control center that integrates pro- and anti-micturition cues. Furthermore, we demonstrate that a cluster of neurons expressing corticotropin-releasing hormone (Crh) in the pontine micturition center (PMC) is electrophysiologically distinct from their Crh-negative neighbors and sends glutamatergic projections to the spinal cord. The activity of PMC Crh-expressing neurons correlates with and is sufficient to drive bladder contraction, and when silenced impairs micturition behavior. These neurons receive convergent input from widespread higher brain areas that are capable of carrying diverse pro- and anti-micturition signals, and whose activity modulates hierarchy-dependent micturition. Taken together, our results indicate that PMC Crh-expressing neurons are likely the integration center for context-dependent micturition behavior.

Developmental expression of estrogen receptor beta in the brain of prairie voles (Microtus ochrogaster).

Here, for the first time, the expression of estrogen receptor beta (ERß) is characterized in the brains of the highly prosocial prairie vole (Microtus ochrogaster). ERß immunoreactivity was compared in weanlings (postnatal Day 21) and adult males and females. The results indicate several major findings. First, unlike ERα, ERß expression is not sexually dimorphic. Second, the adult pattern of ERß-IR is established at the time of weaning, as there were no age-dependent effects on distribution. Finally, ERß does not appear to be as widely distributed in voles compared with rats and mice. High levels of ERß-IR were observed in several regions/nuclei within the medial pre-optic area, ventrolateral pre-optic nuclei, and in the hypothalamus, especially in the paraventricular and supraoptic nuclei. The visualization of ERß in prairie voles is important as the socially monogamous prairie vole functions as a human relevant model system for studying the expression of social behavior and social deficit disorders. Future studies will now be able to determine the effect of treatments on the expression and/or development of ERß in this highly social species.