SUN-LB017 Cellular and Synaptic Reorganization after Exercise Training

Abstract

Hypothalamic Pro-opiomelanocortin (POMC) and Neuropeptide Y/Agouti-Related Peptide (NPY/AgRP) neurons are critical nodes of a circuit within the brain that sense key metabolic cues as well as regulate feeding behavior, energy expenditure, and glucose metabolism. Importantly, intrinsic cellular properties of these neurons are highly sensitive to metabolic state. This includes a rapid reorganization of synaptic inputs and electrophysiological properties in order to facilitate adaptations to altered energy balance. While the cellular properties of these neurons have been investigated in the context of obesity, much less is known about the effects of exercise training. We performed whole-cell patch-clamp electrophysiology on identified POMC and NPY/AgRP neurons after exercise. Exercise resulted in a depolarization and increase in firing rate of arcuate POMC neurons. The increased excitability of POMC neurons was concomitant with increased excitatory input to these neurons. In agreement with recent work suggesting that leptin plays an important role in the synaptic (re)organization of POMC neurons, we found that POMC neurons which express leptin receptors appeared more sensitive to exercise-induced changes in biophysical properties. Opposite to the cellular effects observed in POMC neurons, NPY neurons were inhibited following exercise. These findings were further supported with observed changes of calcium dynamics in vivo. Together, these data support a rapid reorganization of synaptic inputs and biophysical properties in response to exercise, which may facilitate adaptations to altered energy balance and glucose metabolism Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. s presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.