Prominent neurochemicals

• The neuropeptide oxytocin
  Oxytocin
  Oxytocin is a mammalian hormone that acts primarily as a neuromodulator in the brain.Oxytocin is best known for its roles in sexual reproduction, in particular during and after childbirth...
  
  . Oxytocin is involved in the control of maternal behavior. It is synthesized inside magnocellular neurosecretory cell
  Magnocellular neurosecretory cell
  Magnocellular neurosecretory cells are large cells within the supraoptic nucleus and paraventricular nucleus of the hypothalamus. They are also found in smaller numbers in accessory cell groups between these two nuclei, the largest one being the nucleus circularis...
  
  s as a precursor protein that is processed by proteolysis
  Protease
  A protease is any enzyme that conducts proteolysis, that is, begins protein catabolism by hydrolysis of the peptide bonds that link amino acids together in the polypeptide chain forming the protein....
  
   to its shorter active peptide
  Peptide
  Peptides are short polymers of amino acid monomers linked by peptide bonds. They are distinguished from proteins on the basis of size, typically containing less than 50 monomer units. The shortest peptides are dipeptides, consisting of two amino acids joined by a single peptide bond...
  
   form. Specific parts of the brain such as the supraoptic nucleus
  Supraoptic nucleus
  The supraoptic nucleus is a nucleus of magnocellular neurosecretory cells in the hypothalamus of the mammalian brain. The nucleus is situated at the base of the brain, adjacent to the optic chiasm...
  
   produce oxytocin which acts on cells in locations such as the ventral pallidum to produce the behavioral effects of oxytocin. A large amount of oxytocin is made in the hypothalamus
  Hypothalamus
  The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...
  
  , transported to the posterior lobe of the pituitary and released into the blood stream by which it reaches target tissues such as the mammary gland
  Mammary gland
  A mammary gland is an organ in mammals that produces milk to feed young offspring. Mammals get their name from the word "mammary". In ruminants such as cows, goats, and deer, the mammary glands are contained in their udders...
  
  s (milk letdown
  Breastfeeding
  Breastfeeding is the feeding of an infant or young child with breast milk directly from female human breasts rather than from a baby bottle or other container. Babies have a sucking reflex that enables them to suck and swallow milk. It is recommended that mothers breastfeed for six months or...
  
  ). In the diagram inset, oxytocin is shown bound to a carrier protein, neurophysin.
• Other examples of neurochemicals
  • Glutamate is the most common neurotransmitter. Most neurons secrete with glutamate or GABA. Glutamate is excitatory, meaning that the release of glutamate by one cell usually causes adjacent cells to fire an action potential
    Action potential
    In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...
    
    . (Note: Glutamate is chemically identical to the MSG
    Monosodium glutamate
    Monosodium glutamate, also known as sodium glutamate or MSG, is the sodium salt of glutamic acid, one of the most abundant naturally occurring non-essential amino acids....
    
     commonly used to flavor food.)
  • GABA
    Gamma-aminobutyric acid
    γ-Aminobutyric acid is the chief inhibitory neurotransmitter in the mammalian central nervous system. It plays a role in regulating neuronal excitability throughout the nervous system...
    
     is an example of an inhibitory neurotransmitter.
  • Dopamine
    Dopamine
    Dopamine is a catecholamine neurotransmitter present in a wide variety of animals, including both vertebrates and invertebrates. In the brain, this substituted phenethylamine functions as a neurotransmitter, activating the five known types of dopamine receptors—D1, D2, D3, D4, and D5—and their...
    
     is another example of a neurotransmitter. It plays a key role in the functioning of the limbic system
    Limbic system
    The limbic system is a set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, septum, limbic cortex and fornix, which seemingly support a variety of functions including emotion, behavior, long term memory, and olfaction. The term "limbic" comes from the Latin...
    
    , which is involved in emotional function and control. It also plays a part in movement, alertness, and sensations of pleasure.
  • Serotonin
    Serotonin
    Serotonin or 5-hydroxytryptamine is a monoamine neurotransmitter. Biochemically derived from tryptophan, serotonin is primarily found in the gastrointestinal tract, platelets, and in the central nervous system of animals including humans...
    
     plays a regulatory role in mood, sleep, and other areas.
  • Acetylcholine
    Acetylcholine
    The chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system and central nervous system in many organisms including humans...
    
     assists motor function and is involved in memory.
  • Nitric oxide
    Nitric oxide
    Nitric oxide, also known as nitrogen monoxide, is a diatomic molecule with chemical formula NO. It is a free radical and is an important intermediate in the chemical industry...
    
     functions as a neurotransmitter, despite being a gas. It is not grouped with the other neurotransmitters because it is not released in the same way.
  • Endocannabinoids act in the endocannabinoid system
    Endocannabinoid system
    The endocannabinoid system refers to a group of neuromodulatory lipids and their receptors that are involved in a variety of physiological processes including appetite, pain-sensation, mood, and memory; it mediates the psychoactive effects of cannabis and, broadly speaking, includes:* The...
    
     to control neurotransmitter release in a host of neuronal tissues, including the hippocampus, amygdala, basal ganglia, and cerebellum.
  • Eicosanoid
    Eicosanoid
    In biochemistry, eicosanoids are signaling molecules made by oxidation of twenty-carbon essential fatty acids, ....
    
    s act as neurotransmitters via the Arachidonic acid cascade.

See also

• Molecule
  Molecule
  A molecule is an electrically neutral group of at least two atoms held together by covalent chemical bonds. Molecules are distinguished from ions by their electrical charge...
  
  
• Biomolecule
  Biomolecule
  A biomolecule is any molecule that is produced by a living organism, including large polymeric molecules such as proteins, polysaccharides, lipids, and nucleic acids as well as small molecules such as primary metabolites, secondary metabolites, and natural products...
  
  
• Macromolecule
  Macromolecule
  A macromolecule is a very large molecule commonly created by some form of polymerization. In biochemistry, the term is applied to the four conventional biopolymers , as well as non-polymeric molecules with large molecular mass such as macrocycles...
  
  
• Supermolecule
  Supermolecule
  The term supermolecule or supramolecule, was introduced by K.L. Wolf in 1937 to describe hydrogen bonded acetic acid dimers. The study of non-covalent association of complexes of molecules has since developed into the field of supramolecular chemistry...
  
  
• Neurotransmitter
  Neurotransmitter
  Neurotransmitters are endogenous chemicals that transmit signals from a neuron to a target cell across a synapse. Neurotransmitters are packaged into synaptic vesicles clustered beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft, where they bind to...