Oscillating from Neurosecretion to Multitasking Dopamine Neurons

Abstract

In this issue of Cell Reports, Stagkourakis et al. (2016) report that oscillating hypothalamic TIDA neurons, previously thought to be simple neurosecretory neurons controlling pituitary prolactin secretion, control dopamine output via autoregulatory mechanisms and thus could potentially regulate other physiologically important hypothalamic neuronal circuits.

Figure 1. Hypothalamic Neuronal Circuitries with TIDA Neurons

The diagram shows our evolving understanding of the regulation and functions of the tuberoinfundibular dopamine (TIDA) neurons. (A) Then: “neurosecretory” neurons. Classically, these neurons had a well-defined endocrine neurosecretory role involved in the control of prolactin secretion and were controlled by prolactin levels in the blood through a short feedback loop. (B) Now: “multitasking” neuronal networks. New insights suggest a multitasking neuronal network, with local somatodentritic release of dopamine having an autoregulatory feedback on the cells producing it and also influencing adjacent neurons. In addition, axonal branching allows synaptic release of GABA (and potentially dopamine) to regulate both the dopamine neurons themselves and other non-dopamine neurons in the arcuate nucleus.