Somatodendritic organization of pacemaker activity in midbrain dopamine neurons

• 발행기관: 대한생리학회-대한약리학회
• 저자명: Jinyoung Jang Shin Hye Kim Ki Bum Um Hyun Jin Kim Myoung Kyu Park
• 간행물 정보: 『The Korean Journal of Physiology & Pharmacology』제28권 제2호, 165~181쪽, 전체 17쪽
• 주제분류: 의약학 > 의학일반
• 파일형태: PDF
• 발행일자: 2024.03.01

국문 초록

The slow and regular pacemaking activity of midbrain dopamine (DA) neurons requires proper spatial organization of the excitable elements between the soma and dendritic compartments, but the somatodendritic organization is not clear. Here, we show that the dynamic interaction between the soma and multiple proximal dendritic compartments (PDCs) generates the slow pacemaking activity in DA neurons. In multipolar DA neurons, spontaneous action potentials (sAPs) con-sistently originate from the axon-bearing dendrite. However, when the axon initial segment was disabled, sAPs emerge randomly from various primary PDCs, indicating that multiple PDCs drive pacemaking. Ca2+ measurements and local stimulation/per-turbation experiments suggest that the soma serves as a stably-oscillating inertial compartment, while multiple PDCs exhibit stochastic fluctuations and high excitabil-ity. Despite the stochastic and excitable nature of PDCs, their activities are balanced by the large centrally-connected inertial soma, resulting in the slow synchronized pacemaking rhythm. Furthermore, our electrophysiological experiments indicate that the soma and PDCs, with distinct characteristics, play different roles in gluta-mate-induced burst-pause firing patterns. Excitable PDCs mediate excitatory burst responses to glutamate, while the large inertial soma determines inhibitory pause responses to glutamate. Therefore, we could conclude that this somatodendritic or-ganization serves as a common foundation for both pacemaker activity and evoked firing patterns in midbrain DA neurons.

목차

INTRODUCTION

METHODS

RESULTS

DISCUSSION

키워드

Calcium signaling Dopaminergic neurons Glutamatergic synapse Pacemaking Substantia nigra