The adrenal medulla is composed of neuroendocrine chromaffin cells that secrete adrenaline into the systemic circulation to maintain physiological homeostasis and enable the autonomic stress response. How chromaffin cell precursors colonise the adrenal medulla and how they become connected to central nervous system-derived preganglionic sympathetic neurons remain largely unknown. By combining lineage tracing, gene expression studies, genetic ablation and the analysis of mouse mutants, we demonstrate that preganglionic axons direct chromaffin cell precursors into the adrenal primordia.
View Article and Find Full Text PDFVascular endothelial growth factor (Vegfa) is essential for promoting the vascularization of the embryonic murine forebrain. In addition, it directly influences neural development, although its role in the forming forebrain is less well elucidated. It was recently suggested that Vegfa may influence the development of GABAergic interneurons, inhibitory cells with crucial signaling roles in cortical neuronal circuits.
View Article and Find Full Text PDFNeuronal Signal
March 2018
The formation of the central nervous system (CNS) involves multiple cellular and molecular interactions between neural progenitor cells (NPCs) and blood vessels to establish extensive and complex neural networks and attract a vascular supply that support their function. In this review, we discuss studies that have performed genetic manipulations of chick, fish and mouse embryos to define the spatiotemporal roles of molecules that mediate the reciprocal regulation of NPCs and blood vessels. These experiments have highlighted core functions of NPC-expressed ligands in initiating vascular growth into and within the neural tube as well as establishing the blood-brain barrier.
View Article and Find Full Text PDFThe mouse embryo forebrain is the most commonly employed system for studying mammalian neurogenesis during development. However, the highly folded forebrain neuroepithelium is not amenable to wholemount analysis to examine organ-wide neurogenesis patterns. Moreover, defining the mechanisms of forebrain neurogenesis is not necessarily predictive of neurogenesis in other parts of the brain; for example, due to the presence of forebrain-specific progenitor subtypes.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
November 2016
In the adult rodent brain, new neurons are born in two germinal regions that are associated with blood vessels, and blood vessels and vessel-derived factors are thought to regulate the activity of adult neural stem cells. Recently, it has been proposed that a vascular niche also regulates prenatal neurogenesis. Here we identify the mouse embryo hindbrain as a powerful model to study embryonic neurogenesis and define the relationship between neural progenitor cell (NPC) behavior and vessel growth.
View Article and Find Full Text PDFThe developing central nervous system (CNS) is vascularised through the angiogenic invasion of blood vessels from a perineural vascular plexus, followed by continued sprouting and remodelling until a hierarchical vascular network is formed. Remarkably, vascularisation occurs without perturbing the intricate architecture of the neurogenic niches or the emerging neural networks. We discuss the mouse hindbrain, forebrain and retina as widely used models to study developmental angiogenesis in the mammalian CNS and provide an overview of key cellular and molecular mechanisms regulating the vascularisation of these organs.
View Article and Find Full Text PDFFocal cortical dysplasia (FCD) is a localized malformation of cortical development and is the commonest cause of severe childhood epilepsy in surgical practice. Children with FCD are severely disabled by their epilepsy, presenting with frequent seizures early in life. The commonest form of FCD in children is characterized by the presence of an abnormal population of cells, known as balloon cells.
View Article and Find Full Text PDFObject substitution is a type of backward masking that occurs when a mask appears during visual search for a target. We tested the hypothesis that object substitution is an overwriting process triggered by attentional selection of the mask. Impeding attentional selection of a mask by embedding it in an array of distractors eliminated object substitution.
View Article and Find Full Text PDF