Spider VenomPeptideMay Protect Neurons Following Stroke A disulfide-rich spider venom peptide reduced brain damage in rats when given up to 8 hours after a stroke, according to a recent study published in the Proceedings of the National Academy of Sciences. Thework, ledby scientists at theUniversityofQueensland inAustralia, drewonpast findings that a precipitous drop in brain pH followinga strokeactivates acid-sensing ion channel 1a (ASIC1a),which is a keymediator of stroke-induced neuronal damage. Modestly potent ASIC1a inhibitors can provide limited neuroprotection, but this protection does not last beyond 2 to 4 hours after stroke onset in animalmodels. In this latest study, however, researchers discovered a peptide in the venom of the Australian funnel-web spiderHadronyche infensa that potently inhibits ASIC1a by binding to and stabilizing the closed state of the channel. In a rat model of stroke, a single dose (2 ng/kg) of the peptide, named Hi1a, administered into thebrain through intracerebroventricular injectionat2,4,or8hoursafter stroke caused a marked reduction in infarct size. This correlated with improved neurological andmotor function, as well as with preserved neuronal structure in the brain. The investigators observed no adverse effects in the animals during the 72-hour observation period following Hi1a administration. Furtherpreclinicalworkwill be needed to determine whether the neuroprotective effect of Hi1a is durable. In addition to potentially protecting the brain following stroke, Hi1a may be helpful for studying the role of ASIC1a in acidmediatedneuronal injury thatoccurs invarious neurological disorders.