Analysis of the neuronal network of the medullary respiratory center in transgenic rats expressing archaerhodopsin-3 in Phox2b-expressing cells.

Analysis of the neuronal network of the medullary respiratory center in transgenic rats expressing archaerhodopsin-3 in Phox2b-expressing cells. Brain Res Bull. 2018 Nov 15;: Authors: Ikeda K, Kaneko R, Yanagawa Y, Ogawa M, Kobayashi K, Arata S, Kawakami K, Onimaru H Abstract Preinspiratory (Pre-I) neurons in the parafacial respiratory group (pFRG) comprise one of the respiratory rhythm generators in the medulla of the neonatal rat. A subgroup of pFRG/Pre-I neurons expresses the transcription factor Phox2b. To further analyze detailed neuronal mechanisms of respiratory rhythm generation in the neonatal rat, we developed a transgenic (Tg) rat line in which Phox2b-positive cells expressed archaerhodopsin-3 (Arch). Brainstem-spinal cord preparations were isolated from 0-2-day-old Tg newborn rats and were superfused with artificial cerebrospinal fluid equilibrated with 95% O2 and 5% CO2, pH 7.4, at 25-26 °C. Inspiratory fourth cervical ventral root (C4) activity was monitored, and membrane potentials of neurons in the pFRG including Pre-I or inspiratory neurons were recorded. Phox2b-positive cells in the Tg rats were essentially positive for enhanced green fluorescent protein (EGFP) signals (reporter for Arch) in the pFRG. Continuous photo-stimulation of the rostral ventral medulla for up to 90 s by covering the pFRG with green laser light (532 nm) induced a decrease of respiratory rate measured at C4 accompanied by membrane hyper...
Source: Brain Research Bulletin - Category: Neurology Authors: Tags: Brain Res Bull Source Type: research