Spicy foods, capsaicin

Touch Includes the Sensing of Pressure, Temperature, and Other Factors Touch, detected by the skin, senses pressure, temperature, and pain. Specialized nerve cells called nociceptors transmit signals that are interpreted in the brain as pain. A receptor responsible for the perception of pain has been isolated on the basis of its ability to bind capsaicin, the molecule responsible for the hot taste of spicy food. The capsaicin receptor, also called VRl, functions as a cation channel that initiates a nerve impulse. 

The primary counterirritant in group D is capsaicin, a natural substance found in red chili peppers and responsible for the hot, spicy characteristic when used in foods.32,33,48 Capsaicin stimulates the release of substance P from local sensory nerve fibers, depleting substance P stores over time. A period of reduced sensitivity to painful stimuli follows, and transmission of pain impulses to the central nervous system is reduced.42... 

In addition to mating-disruption pheromones, there are a number of naturally occurring, nonpheromonal attractants and repellents. Many are typically used as food additives or in cosmetics or perfumes, and are derived from diverse plant and animal sources. Capsaicin [44], the spicy component of chili peppers, is used in several bird, deer, and rodent repellents. Maple lactone [45], a common food additive and flavoring, is used in traps to attract cockroaches with its stale beer odor. Methyl... 

Over-stimulated pain receptors eventually release endorphins, which are natural pain-killing molecules. VRi receptors can lose their responsiveness after prolonged exposure to capsaicin which is why those who eat a lot of spicy food build up a tolerance to chilli. This is also why capsaicin is used in formulations designed to ease pain, repeated application of which desensitise the nerves. Regular application of a capsaicin cream to aching joints can relieve pain and increase flexibility. Chemotherapy for cancer patients often results in oral pain and sucking capsaicin-laced butterscotch has proved effective. 

Hot and spicy foods contain molecules that stimulate pain-detecting nerve endings. Two such molecules are piperine and capsaicin ... 

Our sense of touch is intimately connected with the sensation of pain. Specialized neurons, termed nociceptors, transmit signals to pain-processing centers in the spinal cord and brain in response to the onset of tissue damage. What is the molecular basis for the sensation of pain An intriguing clue came from the realization that capsaicin, the chemical responsible for the "hot" taste of spicy food, activates nociceptors. 

With prolonged or repeated exposure to capsaicin (3), however, one will eventually beeome insensitive to its effects as excessive cation influx leads to death of the neurons. It is for this reason that people can cultivate a toleranee for spicy food over time, enabling some to have the ability to eat peppers so hot that their mere smell would make the eyes of those less accustomed water profusely. The perhaps more significant feature is this desensitization suggests that capsaicin could serve as an analgesic to mitigate the pain and inflammation associated with several disorders such as... 

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