Nor-epinephrine is a catecholamines which is found in the brain and in the sympathetic division of the autonomic nervous system (ANS).It is hormone produced by the adrenal medulla, the central core of the adrenal glands, located just above the kidneys. Epinephrine also serves as the NTM in brain.
Bio SynthesisIt is synthesized by an important amino acid Tyrosine. An enzyme converts it into L-dopa. another enzyme converts into dopamine and finally the dopamine converts into Nor-epinephrine with the conversion of an enzyme.
Figure
Tyrosine______ L-Dopa______ Dopamine______ Nor-epinephrine.
Systems of Noradernergic Neurons
The neurons which are attached to (NE) are known noradernergic neurons.Almost every region of the brain receives input from noradernergic neurons.The cell bodies of most of these neurons are located in the seven regions of the pons and medulla and one region of the thalamus.The cell bodies of the most important noradrenergic system begin in the locus coreuleus, a neucleus located in the dorsal pons.The axons of these neurons project to widespread regions of the brain.One effect of activation of these neurons is an increase in vigilance attentiveness to events in the environment.
Release of NE
Most neurons that released nor-epinephrine through axonal varicosities and through terminal button on the ends of axonal branches.
Noradernergic Receptors
These are several types of adernergic receptors which are synonymous to the noradernergic receptors and are sensitive to nor-epinephrine.These receptors are divided into four types which are known to be adernergic receptors or nonadernergic receptors. B1, B2, a1, a2. Found in various organs of the body and brain.
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