Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023
Höfundar / Authors: Sana Gadiwalla(1,2), Chloe Guillaume(1), Li Huang(1), Samuel JB White(1), Pétur Henry Petersen(2), Elisa Galliano(1)
Starfsvettvangur / Affiliations: 1. Department of Physiology, Development and Neuroscience, University of Cambridge, CB23DY Cambridge, United Kingdom, 2. Faculty of Medicine, School of Health Sciences, University of Iceland, 101, Reykjavik, Iceland
Kynnir / Presenter: Sana Gadiwalla
Like cortical pyramidal neurons, mitral and tufted cells in the olfactory bulb act as an input convergence hub and transmits information to higher olfactory areas. Since first characterized, they have been classed as distinct projection neurons based on size and location. New in vivo work has shown that these neurons encode complementary olfactory information, akin to parallel channels in other sensory systems. Many ex vivo studies collapse them into a single class, mitral/tufted(M/T), when describing their physiological properties. Using immunohistochemistry and whole-cell patch clamp electrophysiology in acute slices from mice, we attempted to align in vivo and ex vivo data, to find a simple classifier of projection neurons based on intrinsic firing properties.
Our aim was to find an unbiased classifier of putative mitral (pMC) and putative tufted cells (pTC). Light microscopy and immunohistochemistry confirmed that projection neurons in the ML have disparate soma sizes. As M/T cells have been divided based on soma size we used a diameter-based k-means analysis which returned a divisor that mirrors literature. Applied to electrophysiological data we found that pMCs and pTCs are distinct in several intrinsic parameters and homogenous in others. Together these results illustrate the heterogeneity of M/T cells and suggests that they cannot be simply classified based on their intrinsic firing properties alone.