Nociceptive pain

Pain and Nociception Pain Medication Palmitoylation PAMPs... 

In this chapter we highlight the mechanisms and neurochemical basis for nociceptive pain as well as the pain that occurs clinically after tissue injury (inflammatory pain) or nerve damage (neuropathic pain). 

Sensory detection of a noxious stimulus is known as nociception. The perception of such a stimulus, nociceptive pain, is essentially the ouch pain we experience in response to a pinprick or touching a hot or very cold object. Nociceptive pain is an important physiological... 

Although most consumers appreciate the fieriness of chile, capsaicinoids are not perceived through odor or taste receptors but through the nociceptive pain receptors described earlier. The compounds in chile fruit that create the flavor and aroma are produced in the fruit wall. Buttery et al. [90] generated vacuum steam distilled oil from green bell pepper macerate, with well over 40 peaks on subsequent GC/MS analysis. Of these peaks, the major flavor compound associated with bell pepper aroma was 2-methoxy-3-isobutylpyrazine (Fig. 8.1). They also reported several monoterpenoids in abundance, limonene, trans- 3-ocimene, and linalool as well as other aliphatic aldehydes and ketones. The flavor composition of dried red bell pepper powder (sweet paprika) extracted with ether identified 44 key peaks by GC/MS [91]. In these dried samples the key compounds were P-ionone and several furanones. The post-harvest processing and the different fruit maturities as well as possible varietal differences are all causes for the different aromatic profiles. 

Table 2. Medicines used in nociceptive pain conditions — paracetamol and NSAID ...

Paracetamol Unclear. Centrally via 1.5-3 6-15 Baseline drug in nociceptive pain. 

Short-acting NSAIDs - effective in nociceptive pain of inflammatory origin ... 

Table 4. Medicines for nociceptive pain conditions - opioids ...

EOs from different Lippia alba chemotypes showed behavioural effects. Greater effects were presented by chemotype 2 (with citral and limonene), while chemotype 1, containing citral, myrcene and limonene, decreased only the number of rearings in the open-field test [396]. The EO of lemon was found to modulate the behavioural and neuronal responses related to nociception, pain and anxiety [397, 398]. Thus, there is widespread and increasing interest in complementary and alternative medicines using EOs [399]. 

Maione, S., Oliva, P., Marabese, I., Palazzo, E., Rossi, F., Berrino, L., Rossi, F., Filipelli, A. Periaqueductal gray matter metabotropic glutamate receptors modulate formalin-induced nociception, Pain 2000, 85, 183-189. 

Formalin test A small amount of formalin solution is injected into the hind paw of mice or rats. This induces a bi-phasic pain reaction and a specific pain-related behaviour. The first phase represents acute nociceptive pain, whereas the second phase indicates more persistent pain associated with inflammation and tissue damage. Pain behaviour is observed in both phases and measured by means of a scoring system. Besides opioids, compounds active against inflammatory and neuropathic pain can be detected (Dubuisson and Dennis, Pain 1977, 4, 161-174). 

This model represents intense nociceptive pain induced by heat. A hot lightbeam is focussed on the tail of a mouse or rat and the latency for the withdrawal of the tail, a brisk movement called tail... 

Mechanism of action Opioids exert their major effects by interacting with opioid receptors in the CNS and the gastrointestinal tract. Opioids cause hyperpolarization of nerve cells, inhibition of nerve firing, and presynaptic inhibition of transmitter release. Morphine acts at k receptors in lamina I and II of the substantia gelatinosa of the spinal cord, and decreases the release of substance P, which modulates pain perception in the spinal cord. Morphine also appears to inhibit the release of many excitatory transmitters from nerve terminals carrying nociceptive (painful) stimuli. 

Seizures/convulsions, awareness reaction, startle response, vocalization, irritability, decreased abdominal tone, increased secretion, body tremors, decreased grip strength, immobility, motor activity, ataxia, abnormal posture, stereotypy, excretion, decreased respiration, piloerection, loss of righting, pupil size, nociceptive (pain) response, corneal reflex, and pinnal reflex... 

Ayoub SS, Yazid S, Flower RJ (2008) Increased susceptibility of annexin-Al null mice to nociceptive pain is indicative of a spinal antinociceptive action of annexin-Al. Br J Pharmacol 154 1135-1142... 

Simpson DA, Headley PM, Lumb BM (2008) Selective inhibition from the anterior hypothalamus of C- versus A-fibre mediated spinal nociception. Pain 136 305-312 Singh VP, Jain NK, Kulkarni SK (2001) On the antinociceptive effect of fluoxetine, a selective serotonin reuptake inhibitor. Brain Res 915 218-226 Sipe JC, Arbour N, Gerber A, Beutler E (2005) Reduced endocannabinoid immune modulation by a common cannabinoid 2 (CB2) receptor gene polymorphism possible risk for autoimmune disorders. J Leukoc Biol 78 231-238... 

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