Capsaicins

Capsaicin is what makes chili peppers hot. It is an irritant, for mammals, but not for birds. This may be because birds spread the seeds better than mammals. It causes a burning sensation in any mammalian tissue with which it comes in contact. 

Capsaicin is a nonpolar molecule it dissolves in fats and oils, not in water. This is why water does not take away the burning sensation, but whole milk or other fat-containing liquids or foods will. 

As an ingredient in medicines, capsaicin is used to relieve pain from arthritis, muscle aches, and sprains. It is a rubefacient, meaning it dilates blood vessels. The heat effect overwhelms nerves, causing a localized numbing sensation. 

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The spicy flavor of cayenne pepper is due mainly to a substance called capsaicin The fol lowing sequence of steps was used in a synthesis of capsaicin See if you can deduce the struc ture of capsaicin on the basis of this synthesis... 

Synthetics. The lack of spice products to satisfy demand and the wide variation in price and availabihty have caused the manufacture of selected synthetics, chemically identical to the component in the natural spice, to replace the vital components of some spices. However, synthetic organic chemistry is not yet able to manufacture economically the many homologous piperine [94-62-2] components in black pepper or those capsaicin [404-86-4] amides in... 

Capsaicin, an active ingredient in red pepper, is well known for its ability to release and deplete substance P in sensory C fibers. However, this action is not specific for substance P, as neurokinin A, calcitonin gene-related peptide (CGRP), and somatostatin also are released. 

Numerous neuropeptides are beheved to be involved with the transmission or inhibition of pain, and the hope is to utilize this approach as a strategy to induce analgesia. Substance P is reported to be a transmitter of nociceptive impulses (39), and therefore antagonists should be analgesic. Capsaicin [404-86-4], C2gH2yN02, is known to deplete substance P and cause analgesia (40), but its side effects are intolerable. Antagonists to bradykinin [58-82-2], a substance known to induce pain (41), have shown some success in preclinical trials. 

Lachrymator A lachrymator is an irritant that causes tearing (watering of the eyes). Examples include onions, tear gas, and pepper spray (capsaicin). Some typical lachrymating chemicals are thionyl chloride (SOClj) and acrolein (CHj=CH-CHO). Certain chemicals may say lachrymator on the label so treat these with respect. Use these only in a fume hood. Goggles or safety glasses are not adequate protection for lachrymators, because the fumes can still reach your eyes directly or through inhalation. 

Capsaicin receptor" agonists capsaicin, resmiferatoxin II, Via voltage-gated channels maitotoxm ( ) OH ... 

Camphor, molecular model of, 129 specific rotation of, 296 Cannizzaro, Stanislao, 724 Cannizzaro reaction. 724 mechanism of, 724 Caprolactam, nylon 6 from, 1213 Capsaicin, structure of. 78 -curbahlehyde, aldehyde name ending, 696... 

This is an unconventional reflex mediated by capsaicin-sensitive primary afferent neurons. In fact, an adequate stimulus can directly excite a peripheral terminal... 

Capsaicin, also known as N-Vanillyl-8-methyl-6-(E)-noneamide, is the most pungent of the group of compounds called capsaicinoids It is a common ingredient in varieties of pepper such as habanero, Thai, tabasco, cayenne etc. One target with which capsaicin interacts is the capsaicin receptor, an ion channel belonging to the superfamily of TRP channels. Because of the structural relation to other TRP channels and because the vanilloid moiety is an essential component of capsaicin, the capsaicin receptor is also called TRPVI or vanilloid receptor (VR1). It is involved in heat and pain perception. 

These are a subset of sensory neurons having their cell bodies (small to medium size) in dorsal root and in cranial nerve ganglia and possessing nonmyelinated (C-type) or thinly myelinated (A-delta type) fibres. This subset of neurons express transient receptor potential vanilloid type 1 (TRPV1, or vanilloid, or capsaicin receptor) that is excited by capsaicin, the pungent ingredient of chilli. These neurons have been classified as polymodal nociceptors because they can be excited by various noxious stimuli. 

Diuretics This indicates the unique property of capsaicin-sensitive primary afferent neurons to release mediators (neuropeptides and others) from both peripheral and central nervous system terminals upon adequate stimulation. Capsaicin and other chemical (protons) or physical (heat) stimuli release mediators from both peripheral and... 

Edg Receptors central nervous system terminals of these neurons. Capsaicin-induced release of mediators is fundamentally tetrodotoxin resistant despite being ner ve mediated. 

Resiniferatoxin (RTX) is the toxin isolated from the spurge Euphorbia resinifera which is responsible for the powerful burning sensation and skin irritation induced by the milky sap of these plants. Like capsaicin, resiniferatoxin activates TRPV1 currents, but not the currents through other members ofthe TRPV subfamily. 

Summation The overall response is the arithmetic sum of the contribution brought by each receptor (e.g., NKX and NK2). Capsaicin-induced contraction of rat isolated urinary bladder, electrical field stimulation (EFS)-induced nonadrenergic, noncholinergic contraction of the isolated guinea pig bronchus or renal pelvis when SP metabolism is blocked by peptidase inhibitors are all examples of summation. Both NK and NK2r antagonists are required to abolish such kind of response, but each antagonist substantially reduces the response... 

Supra-additivity This is a special case of cooperation where the blockade of a single receptor is not sufficient to reduce the overall response. Capsaicin-induced nonadrenergic, noncholinergic contraction in the guinea pig ileum or common bile duct can be inhibited only when at least two different TK receptors are blocked (e.g., NKX + NK2, NKX + NK3, NK2 + NK3)... 

Members of the TRPV subfamily are activated by a broad range of stimuli including heat (TRPV1, TRPV2, TRPV3 and TRPV4), ligands such as capsaicin... 

TRPVl, also known as the capsaicin- or vanilloid-receptor, is a nonselective cation channel expressed e.g., in neurons of the dorsal root and trigeminal ganglions, which integrates multiple pain-producing stimuli including heat, protons, capsaicin, and resiniferatoxin. In addition, TRPVl currents can be activated by ananda-mide, protein kinase C (PKC), and by hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2). 

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