Different modes of manual acupuncture stimulation differentially modulate cerebral blood flow velocity, arterial blood pressure and heart rate in human subjects.

The psychophysiological effect of different modes of manual acupuncture stimulation was investigated in 12 healthy, right handed, male subjects (mean age 29). The cerebral blood flow velocity (CBFV) in both middle cerebral arteries, arterial blood pressure (BP), heart rate (HR) and the perceived intensity of the stimulation were monitored while an acupuncture needle in the right dorsal thenar muscle (point Hegu, Li 4) was repetitively rotated with either high frequency (4-8 Hz) and low amplitude (hf-la) or low frequency (1-2 Hz) and high amplitude (lf-ha). Response patterns induced by hf-la and 1f-ha [corrected] stimulation differed significantly (P < 0.05) as tested by Student's t-test: (1), 1f-ha [corrected] stimulation was perceived as more intense and induced a more marked right hemispheric CBFV increase; (2), while hf-la stimulation lead to a slight decrease of BP and HR, lf-ha stimulation induced an initial pressor response (increase of BP, decrease of HR) and a more marked long term decrease of BP. Data indicate that the mode of manual acupuncture stimulation has a differential effect on the perceived stimulation intensity, the cerebral activation and the cardiovascular reflex response.

[Investigations on the effect of acupuncture on affective and sensory components of pain in patients with different stages of chronic pain]. / Wirkung der Akupunktur auf die affektivve and sensorische Schmerzbewertung. Untersuchung beipatienten in unterschiedlichen Chronifizierungsstadien]

OBJECTIVES: The aim of the study was to investigate the effects of acupuncture on the affective and sensory experience of pain in chronic pain patients. Furthermore, the study tried to estimate the therapeutical benefit of acupuncture in relation to the stage of chronic pain according to the Mainz pain staging system for chronic pain (MPSS). METHODS: Patients with chronic pain syndromes who received acupuncture treatment answered a standardized pain questionnaire before and after treatment. The questionnaire included the visual-analogue-scale for the intensity of pain, the pain perception scale for the assessment of affective and sensory components of pain perception, and addressed the patients to the three stages of chronic pain (MPSS). RESULTS: From April 1997 to October 1999, patients (n = 165) suffering from chronic headache and facial pain syndromes (23%), spine associated pain syndromes (48%) or other pain conditions (29%) were subsequently included. Treatment with acupuncture showed a more pronounced reduction of the affective assessment than of the sensory assessment of pain. These effects were particularly pronounced in patients assigned to stage 3 of chronic pain (MPSS). CONCLUSIONS: Acupuncture in patients with high-stage chronic pain syndromes preferentially influences the affective dimension of pain perception. For the estimation of the overall clinical outcome of acupuncture treatment, a differentiation between affective and sensory components of pain is recommended.

Altered cerebrovascular response pattern in interictal migraine during visual stimulation.

A dysbalance of the cerebrovascular response during functional activation of the brain has been postulated as a factor in the pathophysiology of migraine. To determine the dynamic pattern of the cerebrovascular response in migraineurs compared with a control group, changes of the cerebral perfusion during cerebral activation were studied with high temporal resolution by functional transcranial Doppler sonography (fTCD). The cerebral blood flow velocity (CBFV) in the right posterior cerebral artery (PCA) and the left middle cerebral artery (MCA) was measured simultaneously during visual stimulation in 19 interictal migraineurs and in 19 age- and sex-matched control subjects. Data were analysed with a previously validated technique based on automated stimulus-related averaging of the CBFV. The MCA migraineurs exhibited a steady increase of CBFV during the stimulation, while normal subjects showed a habituation of the CBFV response. The lack of habituation in migraineurs was significantly (P < or = 0.05) more pronounced across patients with a high attack frequency (> or = 4 per month) compared with migraineurs with a low attack frequency (< 4 per month). In the PCA, compared with normal subjects, migraineurs showed significantly (P < or = 0.05) stronger CBFV changes at the beginning and after the end of stimulation, with a slower decline to baseline. Data are in accordance with electrophysiological findings in migraineurs. It is assumed that a lack of habituation of the cerebrovascular response in migraineurs might contribute to a disturbance of the metabolic homeostasis of the brain that might induce migraine attacks.