摘要:Objective:To explore actions of acupoint injection of Camphol on the permeability of blood-brain barrier and the relevant mechanisms.Methods:30 SD rats were randomly divided into acupoint injection group 1(low dosage, AI-1 group), acupoint injection group 2(high dosage, AI-2 group), electroacupuncture (EA) group."Yamen"(GV 15) was used for injection of Camphol(0.4 g/kg and 0.8 g/kg), and "Baihui" (GV 20) was used for EA stimulation (50 Hz, 5 mA, for 15 min, once again 5 hr later). After treatment, the rats were killed for taking brain tissues that were then processed into supernate for detecting the permeability of blood-brain barrier of rats with spectrophotometric analysis. Results:After treatment, groups can promote the permeability of blood-brain barrier in rats, but the contents of Even's Blue in the brain tissues in the 3 treatment groups all significantly higher than that of control group (P<0.05~0.001), suggesting that acupoint injection and EA can strengthen the permeability of blood-brain barrier to Even's Blue. Comparison among the 3 treatment groups showed that the contents of Even's Blue of AI-1 and AI-2 groups were markedly higher than that of control group (P<0.05). Conclusion:Acupoint injection of Camphol can effectively improve the permeability of blood-brain barrier, which is better than that of electroacupuncture.
摘要:71 7%Objective:To observe whether the primary afferent Aδ-fiber is involved in the signal transmission of the peripheral terminals distributing in the adjacent dermatomes and to investigate the mechanism of sensory transmission along meridian.Methods:SD rats anesthetized with 20% urethane (1 g/kg) were used in this study. The dorsal cutaneous nerve branches of spinal nerves from T 9 to T 12 segments innervating the Bladder Meridian of Foot-Taiyang (BL) area were cut proximally.One peripheral stump end of the cut nerves was dissected into a few filaments for the examination of mechanoceptive properties of single Aδ-fibers and their changes of electrical activity, while another one for antidromically electrical stimulation.Results:Ninety Aδ-units were recorded on 67 intact rats. There were 31.1% rapid adaptation (RA) units and 65.9% slow adaptation (SA) units, with the mean adaptation duration being 20.82±2.51 sec (n=90), the receptive field 17.76±3.40 mm 2 and the mechanoreceptive threshold 0.21±0.03 mN.There were 1 to 3 sensitive points (1.79±0.11) in each receptive field and 77.3% (n=88) of them distributed along BL. After an electrical stimulation(0.45 mA,0.1 ms, 20 Hz, for 10 sec) was delivered to the stimulated nerve, the size of the receptive field of 71.9% (n=64) of Aδ-fibers extended. The mean area of receptive fields of all the examined units enlarged from 17.76±3.40 mm 2 to 71.98±13.07 mm 2 (P<0.001) and the receptive field of 74.6% (n=60) units changed from a dot, round or ellipse shape, with its long axis being in parallel with the longitudinal axis of the body. The number of sensitive point in each receptive field increased to 3.08±0.25 from 1.79±0.11, (P<0.01). The mechanoceptive threshold of 71.7% (n=60) units decreased to 0.12±0.04 mN (P<0.001). The changes of mechanoceptive properties appeared simultaneously with discharge changes but lasted longer than that of discharge change (P<0.01).Conclusion:These results suggest that low-threshold mechanoreceptive Aδ-fibers can be activated by antidromically electrical stimulation of cutaneous nerve of the adjacent spinal segment, indicating that the signal transmission occurs between two endings of peripheral afferent nerves from the adjacent spinal segments without any involvement of central nervous system, and Aδ-fibers are involved in the process of signal transmission. This may be an important mechanism of sensory transmission along meridian in traditional Chinese medicine.