Using Intrinsic Flavoprotein and NAD(P)H Imaging to Map Functional Circuitry in the Main Olfactory Bulb
نویسندگان
چکیده
Neurons exhibit strong coupling of electrochemical and metabolic activity. Increases in intrinsic fluorescence from either oxidized flavoproteins or reduced nicotinamide adenine dinucleotide (phosphate) [NAD(P)H] in the mitochondria have been used as an indicator of neuronal activity for the functional mapping of neural circuits. However, this technique has not been used to investigate the flow of olfactory information within the circuitry of the main olfactory bulb (MOB). We found that intrinsic flavoprotein fluorescence signals induced by electrical stimulation of single glomeruli displayed biphasic responses within both the glomerular (GL) and external plexiform layers (EPL) of the MOB. Pharmacological blockers of mitochondrial activity, voltage-gated Na+ channels, or ionotropic glutamate receptors abolished stimulus-dependent flavoprotein responses. Blockade of GABAA receptors enhanced the amplitude and spatiotemporal spread of the flavoprotein signals, indicating an important role for inhibitory neurotransmission in shaping the spread of neural activity in the MOB. Stimulus-dependent spread of fluorescence across the GL and EPL displayed a spatial distribution consistent with that of individual glomerular microcircuits mapped by neuroanatomic tract tracing. These findings demonstrated the feasibility of intrinsic fluorescence imaging in the olfactory systems and provided a new tool to examine the functional circuitry of the MOB.
منابع مشابه
Using Manganese Enhanced MRI to Reveal Active Olfactory Circuitry in Response to Odorant Stimuli
Introduction Olfactory stimuli activate different combinations of olfactory sensory neurons (OSNs) in the olfactory epithelium. Since OSNs expressing the same odorant receptor (OR) project axons to the main olfactory bulb (MOB) and innervate the same set of glomeruli in a stereotypic fashion, the activation of OSNs elicited by odorants is transformed to a spatial pattern in the MOB, i.e., an od...
متن کاملImaging Odor-Evoked Activities in the Mouse Olfactory Bulb using Optical Reflectance and Autofluorescence Signals
In the brain, sensory stimulation activates distributed populations of neurons among functional modules which participate to the coding of the stimulus. Functional optical imaging techniques are advantageous to visualize the activation of these modules in sensory cortices with high spatial resolution. In this context, endogenous optical signals that arise from molecular mechanisms linked to neu...
متن کاملFunctional ultrasound imaging reveals different odor-evoked patterns of vascular activity in the main olfactory bulb and the anterior piriform cortex
Topographic representation of the outside world is a key feature of sensory systems, but so far it has been difficult to define how the activity pattern of the olfactory information is distributed at successive stages in the olfactory system. We studied odor-evoked activation patterns in the main olfactory bulb and the anterior piriform cortex of rats using functional ultrasound (fUS) imaging. ...
متن کاملAutomatic segmentation of odor maps in the mouse olfactory bulb using regularized non-negative matrix factorization
Segmentation of functional parts in image series of functional activity is a common problem in neuroscience. Here we apply regularized non-negative matrix factorization (rNMF) to extract glomeruli in intrinsic optical signal (IOS) images of the olfactory bulb. Regularization allows us to incorporate prior knowledge about the spatio-temporal characteristics of glomerular signals. We demonstrate ...
متن کاملFunctional Imaging of Mitochondria in Saponin-permeabilized Mice Muscle Fibers
Confocal laser-scanning and digital fluorescence imaging microscopy were used to quantify the mitochondrial autofluorescence changes of NAD(P)H and flavoproteins in unfixed saponin-permeabilized myofibers from mice quadriceps muscle tissue. Addition of mitochondrial substrates, ADP, or cyanide led to redox state changes of the mitochondrial NAD system. These changes were detected by ratio imagi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 11 شماره
صفحات -
تاریخ انتشار 2016