NTI » Glossary

Anti-edema effect:	Reduction of fluid buildup and associated swelling in damaged body tissues.
Cerebral edema:	Swelling in the brain, commonly associated with brain tumors, head injury and stroke. Swelling within the closed space of the skull can damage brain tissue and restrict blood flow to the brain.
Calcium channel:	A doughnut-shaped protein imbedded in the membrane of neurons (see neuron). Charged calcium molecules, called ions, flow through the channel into the neuron, causing the neuron to change electrical charge and fire. When too much calcium enters the neuron, however, it may be injured. The NMDA receptor controls a calcium channel.
Channel blocker:	Compound which remains for a long period of time in a receptor channel or prevents the channel from opening. Such compounds may interfere with normal receptor activity.
Corticosteroids:	Synthetic versions of steroidal compounds that are produced naturally in the body and modulate the body's immune system and inflammatory response.
Dementia:	A condition common in Alzheimer's patients and patients with AIDS characterized by loss of coordination, forgetfulness, confusion, changes in personality, and inability to concentrate.
Diabetic neuropathy:	A complication of diabetes characterized by progressive weakness, numbness or pain in a body region. Caused by inadequate functioning of the nerves. The most common form, peripheral neuropathy, involves damage to small sensory nerves in the lower extremities (usually the feet). Neuropathic pain is a common symptom.
Edema:	The accumulation of fluid in damaged tissues, causing painful and dangerous swelling.
Excitotoxicity:	A cascading cycle of neuronal injury and death in the central nervous system. Injured neurons release excessive amounts of glutamate which cause toxic levels of calcium flow into neighboring cells through NMDA receptor calcium channels. These cells swell and rupture, releasing more glutamate into the cellular environment (see "neuron" and "glutamate").
Glutamate:	The principal excitatory neurotransmitter in the brain. Neurons release glutamate in order to excite neighboring cells; they receive a "wake up" signal when glutamate binds with NMDA receptors imbedded in their cell membrane (see NMDA receptor and neuron). When excessive levels of glutamate are present, neurons are overexcited and suffer injury and death.
Focal cerebral edema:	A distinct type of edema caused by brain tumors. Fluid flows from small blood vessels in damaged areas into the interstitial spaces between brain cells and the vessels, which causes swelling and pressure.
Modulator:	Compound which acts like a "volume control" to regulate a natural process in the body, such as receptor activity. NTI believes that Memantine is a modulator of the NMDA receptor calcium channel because it regulates the flow of calcium ions through the channel (see "calcium channel").
Neurological:	Pertaining to the function of the nervous system (as in neurological disease).
Neuron:	Nerve cell which generates and conducts electrical signals. Neurons are concentrated in the brain and spinal cord.
Neuronal dysfunction:	Abnormal function of the body's neural network.
Neuropathic pain:	Persistent, chronic pain without an obvious cause. Often associated with damage to nerves or nerve fibers. Such pain is associated with the transmission of abnormal pain signals from injured peripheral nerves to neurons in the brain and spinal cord.
Neuroprotection:	The effect of potential drugs which may inhibit nerve cell injury and death. Usually refers to protection against nerve cell death as a result of glutamate-induced overexcitation (see glutamate). More generally, refers to protection against nerve cell death associated with acute or chronic neurological conditions.
Neurotransmitter:	Nerve cells communicate with each other by sending chemical messages called neurotransmitters that either excite or inhibit signal transduction. They bind to receptors located on the cell membranes of neurons.
NMDA receptor:	A protein molecule imbedded in the membrane of nerve cells which binds with glutamate, the principal excitatory neurotransmitter in the brain (see glutamate).
NMDA receptor antagonists:	Drug candidates that prevent excessive activation of the NMDA receptor by reducing the potentially damaging and lethal influx of calcium into neurons.
Peptide:	A molecule similar to but smaller than a protein. Peptides are made of amino acids, the building blocks of proteins. Many peptides occur naturally in the body, including a variety of hormones.
Peritumoral brain edema:	Swelling in the brain caused by a tumor. Plasma fluids and white blood cells build up in the tissues surrounding the tumor, causing life-threatening pressure within the skull.
Orphan Drug Designation:	Food and Drug Administration designation for drugs for rare diseases or conditions. Provides for seven-year market exclusivity for companies developing such drugs.