Hsieh Jen-Chuen, Ståhle-Bäckdahl Mona, Hägermark Östen, Stone-Elander Sharon, Rosenquist Göran, Ingvar Martin
Section of Clinical Neurophysiology, Department of Clinical Neuroscience, Karolinska Hospital/Karolinska Institute, Stockholm Sweden Department of Dermatology, Karolinska Hospital/Karolinska Institute, Stockholm, Sweden Karolinska Pharmacy, Karolinska Hospital/Karolinska Institute, Stockholm, Sweden Section of Neuroanesthesia and Pain Unit, Department of Anesthesiology, Veterans General Hospital-Taipei and School of Medicine, National Yang-Ming University, 11217 Taipei, Taiwan.
Pain. 1996 Feb;64(2):303-314. doi: 10.1016/0304-3959(95)00129-8.
The study was conducted to investigate which areas of the brain respond to a painful encounter of minor dermal injury (a model of clinical pain) elicited by intracutaneous injection of a minute amount of ethanol. Four healthy volunteers (27-46 years) were subjected to positron emission tomographic (PET) investigation of regional cerebral blood flow (rCBF), using [15O]butanol as tracer. The ethanol (20 microliters, 70%) and saline (20 microliters, 0.9%) were injected intracutaneously 3 times in a single-blinded, semi-randomised manner for the pain experiment. All the injections were performed, adjacent to each other, at the lateral aspect of the right upper arm. Subjective sensory intensity of pain, unpleasantness and anxiety were rated with separate 100-mm visual analogue scales together with the Spielberger's State Anxiety Inventory (Spielberger et al. 1970) and heart rate. Paired-subtraction (pixel-by-pixel) between ethanol and saline was performed. Traumatic pain significantly caused higher ratings of intensity and affect scales, i.e., pain intensity, unpleasantness and increased sympathetic activity (evidenced by tachycardia). In contrast the anxiety rating remained unchanged. Acute traumatic nociceptive pain prominently activated the hypothalamus and periaqueductal gray (PAG). In addition, activations of the prefrontal cortex (PFC), insular, anterior cingulate cortex (ACC), posterior parietal cortex (PPC), primary motor/somatosensory areas (MI/SI: face, upper arm), supplementary motor area (SMA), and cerebellum were also demonstrated. The central processing of the pain-relevant/anticipatory arousal also engaged the PAG. This study demonstrates the involvement of the human cerebral cortex in perception, arousal, cognitive evaluative processes, and, hence, affective reactions (somatic/ autonomic outflow) associated with pain. The pain stimulus of traumatic character may, by its very nature, evoke the central processing to involve both the hypothalamus and the PAG.
本研究旨在调查大脑的哪些区域会对皮内注射微量乙醇引发的轻微皮肤损伤（一种临床疼痛模型）的疼痛刺激产生反应。四名健康志愿者（27 - 46岁）接受了正电子发射断层扫描（PET）对局部脑血流量（rCBF）的研究，使用[15O]丁醇作为示踪剂。在疼痛实验中，以单盲、半随机的方式皮内注射乙醇（20微升，70%）和生理盐水（20微升，0.9%）各3次。所有注射均在右上臂外侧彼此相邻的位置进行。使用单独的100毫米视觉模拟量表以及斯皮尔伯格状态焦虑量表（斯皮尔伯格等人，1970年）和心率对疼痛的主观感觉强度、不愉快程度和焦虑程度进行评分。对乙醇和生理盐水进行逐像素配对减法分析。创伤性疼痛显著导致强度和情感量表评分更高，即疼痛强度、不愉快程度增加以及交感神经活动增强（以心动过速为证）。相比之下，焦虑评分保持不变。急性创伤性伤害性疼痛显著激活了下丘脑和导水管周围灰质（PAG）。此外，还显示前额叶皮质（PFC）、岛叶、前扣带回皮质（ACC）、后顶叶皮质（PPC）、初级运动/躯体感觉区（MI/SI：面部、上臂）、辅助运动区（SMA）和小脑被激活。与疼痛相关/预期性唤醒的中枢处理也涉及PAG。本研究表明人类大脑皮层参与了与疼痛相关的感知、唤醒、认知评估过程，以及因此产生的情感反应（躯体/自主神经输出）。创伤性疼痛刺激因其本质可能会引发中枢处理，涉及下丘脑和PAG两者。
