norepinephrine along with an extra enzyme that converts norepinephrine to

Norepinephrine along with an extra enzyme that

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norepinephrine, along with an extra enzyme that converts norepinephrine to epinephrine Serotonin is synthesized from the amino acid tryptophan and is classified as an indolamine Neurons that release norepinephrine are called noradrenergic ; those that release epinephrine are called adrenergic There are two reasons for this name o Epinephrine and norepinephrine used to be called adrenaline and noradrenaline, respectively, by many scientists, until a drug company registered adrenalin as a brand name
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o The other reason is the name would get too complicated Acetylcholine A small molecule neurotransmitter that is in one major respect like a professor who is late for lecture - in a class by itself Created by adding a n acetyl group to a choline molecule Acetylcholine is the neurotransmitter at neuromuscular junctions, at many of the synapses in the autonomic nervous system and at synapses in several parts of the central nervous system Neurons that release acetylcholine are said to be cholinergic Unconventional Neurotransmitters One class of unconventional neurotransmitters, the soluble-gas neurotransmitters, includes nitric oxide and carbon monoxide These neurotransmitters are produced in the neural cytoplasm and immediately diffuse through the cell membrane into the extracellular fluid and then into the nearby cells They easily pass through cell membranes because they are soluble in lipids Once inside another cell, they stimulate the production of a second messenger and in a few seconds are deactivated by being converted to other molecules Difficult to study because they exist for only a few seconds Soluble gas neurotransmitters have been shown to be involved in retrograde transmission At some synapses, they transmit feedback signals from the post synaptic neuron back to the presynaptic neuron The function of retrograde transmission seems to be to regulate the activity of presynaptic neurons Endocannabinoids – another class of unconventional neurotransmitters, recently discovered o Neurotransmitters that are similar to THC, the main psychoactive constituent of marijuana o Two have been discovered o The most widely studied is annandamide o Endocannabinoids are produced immediately before they are release o Are synthesized from fatty compounds in the cell membrane they tend to be released from the dendrites and cell body, and they tend to have most of their effects on presynaptic neurons, inhibiting subsequent synaptic transmission Neuropeptides The actions of these depend on its amino aid sequence There of the five categories acknowledge that neuropeptides often function in multiple capacities, not just as neurotransmitters o Pituitary peptide: contains neuropeptides that were firstidentified as hormones released b the pituitary o Hypothalamic peptides contains neuropeptides that were first identified as hormones released by the hypothalamus o Brain gut peptides contains neuropeptides tat were first discovered in the gut
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o Opioid peptides
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