青蒿琥酯在奶牛体内的药代动力学与代谢

青蒿琥酯(artesunate,AS)是抗疟新药青蒿素的一个活性衍生物。近年来我国兽医工作者将其用于治疗牛羊泰勒氏焦虫病及双芽、巴贝斯焦虫病、鸡球虫病和耕牛血吸虫病,也收到了满意的效果。AS在大白鼠、兔、狗及人体内的药代动力学研究已见报道。本     

In vivo inhibition of epileptiform afterdischarges in rat hippocampus by light-activated chloride channel,stGtACR2

Aims

The blue light-sensitive chloride-conducting opsin, stGtACR2, provides potent optogenetic silencing of neurons. The present study investigated whether activation of stGtACR2 in granule cells of the dentate gyrus (DG) inhibits epileptic afterdischarges in a rat model.

Methods

Rats were bilaterally injected with 0.9 μl of AAV2/7-CaMKIIα-stGtACR2-fusionred in the DG. Three weeks later, afterdischarges were recorded from the DG by placing an optrode at the injection site and a stimulation electrode in the perforant path (PP). Afterdischarges were evoked every 10 min by unilateral electrical stimulation of the PP (20 Hz, 10 s). During every other afterdischarge, the DG was illuminated for 5 or 30 s, first ipsilaterally and then bilaterally to the PP stimulation. The line length metric of the afterdischarges was compared between illumination conditions.

Results

Ipsilateral stGtACR2 activation during afterdischarges decreased the local field potential line length only during illumination and specifically at the illuminated site but did not reduce afterdischarge duration. Bilateral illumination did not terminate the afterdischarges.

Conclusion

Optogenetic inhibition of excitatory neurons using the blue-light sensitive chloride channel stGtACR2 reduced the amplitude of electrically induced afterdischarges in the DG at the site of illumination, but this local inhibitory effect was insufficient to reduce the duration of the afterdischarge.