Basal forebrain GABAergic innervation of olfactory bulb periglomerular interneurons

Abstract

17Olfactory bulb circuits transform a spatially organized olfactory sensory input into a

Brief Sensory Deprivation Triggers Cell Type-Specific Structural and Functional Plasticity in Olfactory Bulb Neurons

“…7A; (Byrne et al, 2020;Galliano et al, 2018;Vaaga et al, 2017)). The remaining tdT-positive/TH-negative nondopaminergic labelled OB neurons in these mice are of the calretinin-expressing OB interneuron class and can be readily identified by their unique physiological properties (Byrne et al, 2020;Pignatelli et al, 2005;Sanz Diez et al, 2019), so these were excluded from our analyses. Anaxonic DA cells, which are over-represented in DAT-tdTomato mice (Galliano et al, 2018), were functionally classified by assessing the nature of their action potential phase plane plot of single spikes fired in response to 10 ms somatic current injection (Fig.…”

Somatostatin Serves a Modulatory Role in the Mouse Olfactory Bulb: Neuroanatomical and Behavioral Evidence

“…Discrete groups of GFP-labeled neurons are found after 3 dpi in the AON, dorsal tenia tecta (DTT), piriform and entorhinal cortex, medial amygdala and ventral CA1 of the hippocampus, all structures involved in olfactory and emotional processing and previously reported to send back projections to the OB (Hintiryan et al, 2012; Miyamichi et al, 2013; Diodato et al, 2016). Most centrifugal projections are glutamatergic but basal forebrain nuclei send cholinergic fibers as well as GABAergic fibers to the OB (Nunez-Parra et al, 2013; Case et al, 2017; Sanz Diez et al, 2017) which may mediate disinhibition of the principal cells (Gracia-Llanes et al, 2010). Progressively, GFP infected neurons appear in the hypothalamic paraventricular nucleus, claustrum and BLA, suggesting that the virus retrogradely infects second- or third-order neurons.…”

“…These reciprocal synaptic interactions induce local field potential oscillations, including gamma oscillations which are involved in fast discrimination between close stimuli in the OB (Frederick et al, 2016) and feed-forward transmission of the signal to downstream associational regions of the olfactory cortex (Kay, 2014). Finally, retrograde afferents from the olfactory cortex and other brain structures also target the OB (Shipley and Ennis, 1996; Lepousez and Lledo, 2013; Kay, 2014; Wilson et al, 2014; Diodato et al, 2016; Case et al, 2017), and modify local synaptic activity (Balu et al, 2007; Boyd et al, 2012; Devore and Linster, 2012; Markopoulos et al, 2012; Soria-Gómez et al, 2014; Brunert et al, 2016; Sanz Diez et al, 2017).…”

Target-specific control of olfactory bulb periglomerular cells by GABAergic and cholinergic basal forebrain inputs

“…BF GABAergic afferents innervate all layers of the OB at least as densely as cholinergic axons but only few studies have examined their function in odor processing (Nunez-Parra et al 2013, Bohm et al 2020. This is a difficult question because GABAergic projections to the OB likely arise from several populations of BF neurons (Sanz Diez et al 2019). Moreover, electrophysiological evidence indicate that BF GABAergic afferents innervate several types of GABAergic interneurons.…”

“…Moreover, electrophysiological evidence indicate that BF GABAergic afferents innervate several types of GABAergic interneurons. These targets include granule cells and PG cells which inhibit principal neurons (Nunez-Parra et al 2013, Sanz Diez et al 2019, Hanson et al 2020, Villar et al 2021) and deep short-axon cells which inhibit granule cells and PG cells (Case et al 2017, Sanz Diez et al 2019). Thus, depending on their target BF GABAergic inputs may inhibit or disinhibit principal neurons.…”