what is the function of the proteins secreted by cells of the ventral midline of the spinal cord
patterning the ventral axis
title: Spinal cord text: the neural tube, its lateral walls thicken and form a longtitudinal groove called the sulcus limitans. This extends the length of the spinal cord into dorsal and ventral portions as well. Meanwhile, the overlying ectoderm secretes bone morphogenetic protein (BMP). This induces the roof plate to begin to secrete BMP, which will induce the alar plate to develop sensory neurons. Opposing gradients of such morphogens as BMP and SHH form different domains of dividing cells along the dorsal ventral axis. Dorsal root ganglion neurons differentiate from neural crest progenitors. As the dorsal and ventral column cells proliferate, the lumen of title: Spinal cord text: the neural tube narrows to form the small central canal of the spinal cord. The alar plate and the basal plate are separated by the sulcus limitans. Additionally, the floor plate also secretes netrins. The netrins act as chemoattractants to decussation of pain and temperature sensory neurons in the alar plate across the anterior white commissure, where they then ascend towards the thalamus. Following the closure of the caudal neuropore and formation of the brain's ventricles that contain the choroid plexus tissue, the central canal of the caudal spinal cord is filled with cerebrospinal fluid. Earlier findings by Viktor Hamburger title: Hormone text: (amines and peptide or protein hormones) are water-soluble and act on the surface of target cells via second messengers; steroid hormones, being lipid-soluble, move through the plasma membranes of target cells (both cytoplasmic and nuclear) to act within their nuclei. Hormone secretion may occur in many tissues. Endocrine glands are the cardinal example, but specialized cells in various other organs also secrete hormones. Hormone secretion occurs in response to specific biochemical signals from a wide range of regulatory systems. For instance, serum calcium concentration affects parathyroid hormone synthesis; blood sugar (serum glucose concentration) affects insulin synthesis; and because the outputs title: Dorsal column–medial lemniscus pathway text: oblongata, where lower body axons in the gracile tract connect (synapse) with neurons in the gracile nucleus, and upper body axons in the cuneate tract synapse with neurons in the cuneate nucleus. First-order neurons secrete substance P in the dorsal horn as a chemical mediator of pain signaling. The dorsal horn of the spinal cord transmits pain and non-noxious signals from the periphery to the spinal cord itself. Adenosine is another local molecule that modulates dorsal horn pain transmission The neurons in these two nuclei (the dorsal column nuclei) are second-order neurons. Their axons cross over to the other side title: Spinal cord text: is also the location of groups of spinal interneurons that make up the neural circuits known as central pattern generators. These circuits are responsible for controlling motor instructions for rhythmic movements such as walking. The spinal cord is the main pathway for information connecting the brain and peripheral nervous system. Much shorter than its protecting spinal column, the human spinal cord originates in the brainstem, passes through the foramen magnum, and continues through to the conus medullaris near the second lumbar vertebra before terminating in a fibrous extension known as the filum terminale. It is about long in men and