Urch Catherine
Consultant in Palliative Medicine, St Marys and Royal Brompton Hospitals, London, UK.
Rev Pain. 2007 Aug;1(1):2-6. doi: 10.1177/204946370700100102.
Acute (normal) pain transmission is part of a survival response to prevent tissue damage and attend to and protect damaged tissue.A cycle of afferent transmission, response to stimuli, followed by temporary hypersensitivity, then attenuation and resolution occurs.Primary afferent, spinal cord ascending and descending pathways are fixed; however the response elicited is highly dynamic and not a linear relationship with input intensity.Somatic inputs are topographically accurate, in contrast to diffuse visceral inputs.Primary afferents code differentially for stimuli (heat, acid, pressure etc) and intensity.The dorsal horn allows extensive modulation of initial inputs, either excitation or inhibition.Higher CNS areas allow extensive modulation of inputs, account for the conscious recognition of pain: the intensity, location, emotional and memory aspects.Descending pathways arising from midbrain regions can be inhibitory or excitatory.
急性（正常）疼痛传导是一种生存反应的一部分，旨在防止组织损伤，并照料和保护受损组织。存在一个传入传导、对刺激的反应、随后的暂时超敏反应、然后是减弱和消退的循环。初级传入神经、脊髓的上行和下行通路是固定的；然而，引发的反应是高度动态的，与输入强度并非线性关系。与弥散的内脏传入神经不同，躯体传入神经在地形学上是精确的。初级传入神经对刺激（热、酸、压力等）和强度进行差异编码。背角允许对初始输入进行广泛的调制，包括兴奋或抑制。更高的中枢神经系统区域允许对输入进行广泛的调制，解释了对疼痛的意识认知：强度、位置、情感和记忆方面。从中脑区域产生的下行通路可以是抑制性的或兴奋性的。
