Optogenetics is a biological technique which provides a means of modulating the selective neural pathways through the activation of light sensitive proteins. Through this genes can be manipulated along the neural pathways to either stimulate or inhibit respiratory rhythm and pattern.
The neural control of breathing involves an integrated orchestration between several dedicated brain stem circuits, along with higher brain areas such as cortex, limbic system and hypothalamus. This higher brain function interprets peripheral feedback and innervates the muscles and lungs to regulate breathing rates and rhythms.
CONSCIOUS CONTROL, SPONTANEOUS BREATHING
Optogenetics studies targeting respiratory centers in the brain stem can be paired with whole body plethysmography (WBP) to measure pulmonary function as result of optical manipulation of the nervous system. WBP permits a continuous assessment of breathing patterns in freely moving, conscious subjects and provides important parameters such as breathing frequency and duration, estimates of tidal volume and minute ventilation. iox2 software allows for customized protocols and analysis on a breath by breath basis to capture respiratory changes in real-time.
The WBP chamber can be combined with a removable swivel tower, attached to the top of the chamber which allows for the subject to have full range of motion while keeping the integrity of the tethered fiber optic cable.
- Selective optogenetic stimulation of the retrotrapezoid nucleus in sleeping rats activates breathing without changing blood pressure or causing arousal or sighs. – Burke, P.G. et al. Journal of Applied Physiology, 118(12): 1491-1501
- Selective optogenetic activation of rostral ventrolateral medullary catecholaminergic neurons produces cardiorespiratory stimulation in conscious mice. – Abbott, S.B.G. et al. Journal of Neuroscience, 33(7):3164-3177
- State-dependent control of breathing by the retrotrapezoid nucleus. – Burke, P.G. et al. The Jounal of Physiology, 593(13): 2909-2926.