The effect of auricular acupuncture on anaesthesia with desflurane.

In most acupuncture studies it is difficult or even impossible to conduct a truly double-blind trial. However, this is possible when treatments are carried out on anaesthetised patients. Because acupuncture provides analgesia, we tested the hypothesis that needle stimulation of a combination of four ear acupoints would significantly reduce anaesthetic requirement. Ten healthy volunteers were anaesthetised with desflurane and randomly assigned to no treatment or acupuncture; the alternative treatment was given on a subsequent study day. Auricular acupuncture was performed with needles placed at the Shen Men, Thalamus, Tranquiliser and Master Cerebral Points on the right ear. Anaesthetic requirement, determined by the Dixon up-and-down method, was defined by the average desflurane concentration that prevented purposeful movement of the extremities in response to noxious electrical stimulation. Volunteers required a greater desflurane concentration to prevent movement on the control than on the acupuncture day: 4.9 (0.7; SD) vs. 4.4 (0.8) vol. %, p = 0.003. Acupuncture thus reduced anaesthetic requirement by 8.5 (7)%.

Effect of systemic zinc administration on delayed neuronal death in the gerbil hippocampus.

The divalent cation zinc has been reported to possess several physiological properties such as blocking apoptotic cell death through an inhibitory effect on Ca(2+)-Mg2+ endonuclease activity, or modulating the neurotoxicity via glutamate receptor subtypes. In the present study, we investigated the effect of peripherally injected zinc on delayed neuronal death seen in the hippocampus after transient global ischemia, in order to elucidate a possible beneficial role on zinc in ischemic neuronal cell death. Forty-five adult Mongolian gerbils of both sexes underwent transient bilateral clipping of the common carotid arteries for 3 min. In the pretreated animals, ZnCl2 (20 mg/kg) was injected subcutaneously once, 1 h before ischemia (superacute group; n = 6) or twice at 24 and 48 h before ischemia (subacute group; n = 14). Histological survey was carried out 3 days later by in situ DNA fragmentation method and 4 days later by hematoxylin-eosin staining by semiquantatively counting dead neurons in the CA1 sector. Subacute zinc pre-administration significantly reduced the nuclear damage and subsequent neuronal death; however, superacutely pre-administered zinc did not protect hippocampal neurons against ischemia but it did not aggravate the effect of ischemia, either. The present study suggested that transfer of exogenous zinc into the intracellular space is required for neuroprotection, presumably via the anti-endonuclease activity.

Differential expressions of the eph family of receptor tyrosine kinase genes (sek, elk, eck) in the developing nervous system of the mouse.

To examine the roles of the eph subfamily of receptor tyrosine kinase (RTK), we isolated mouse cDNAs for sek, elk, and eck and localized their mRNAs in the developing mouse, with particular reference to the CNS development, by in situ hybridization. sek mRNA is most abundantly expressed throughout development; sek was detected in the germinal layer of the embryonic CNS during mid- to late-gestation and was widely expressed in the early postnatal brain. elk was expressed in the mantle layer of the embryonic CNS and showed a distribution complementary to that of sek. Differential expression of sek and elk was also observed in the early postnatal cerebellum; sek was expressed in the Purkinje cells, while elk was detected in the granule cells. eck was moderately expressed in the germinal layer of the embryonic CNS at mid-gestation, but its expression decreased as development proceeded. These spatio-temporally different patterns of gene expression suggest that these RTKs have distinct roles in mouse development despite their structural homology.