Modulation by the Noble Gas Helium of Tissue Plasminogen Activator: Effects in a Rat Model of Thromboembolic Stroke*

Abstract

In a clinical perspective for the treatment of acute ischemic stroke, these data suggest that helium 1) should not be administered before or together with tissue plasminogen activator therapy due to the risk of inhibiting the benefit of tissue plasminogen activator-induced thrombolysis; and 2) could be an efficient neuroprotective agent if given after tissue plasminogen activator-induced reperfusion.

Effects of combined helium pre/post‐conditioning on the brain and heart in a rat resuscitation model

“…David et al. demonstrated that helium induced neuroprotection in a model of cerebral ischemia is abolished when helium is administered at 33°C, suggesting helium induced hypothermia as a mediator of protection …”

“…To minimize experimental bias, animals were kept at all times on a heating plate at 37°C in order to avoid an effect of helium induced hypothermia, a condition shown to be neuroprotective by itself in rat models of ischemic stroke . Furthermore, we used pentobarbital anesthesia as volatile anesthetics (isoflurane, desflurane and sevoflurane) are known to induce pre‐ and post‐conditioning of the heart …”

Medical gases for stroke therapy: summary of progress 2015–2016

“…Abraini’s group reported that helium is an efficient neuroprotective agent able to attenuate tPA-induced thrombolysis consequently decreasing brain injury in thromboembolic model of stroke in rats 27. In the clinic practice, helium would be a safe treatment for patients receiving thrombolytic agent.…”

Hyperbaric oxygen increases tissue-plasminogen activator-induced thrombolysis in vitro, and reduces ischemic brain damage and edema in rats subjected to thromboembolic brain ischemia

“…Male Sprague-Dawley rats (n = 34) weighing 250-275 g were subjected to middle cerebral artery occlusion by administration of an autologous blood clot by the intraluminal method as described previously (Haelewyn et al, 2016). Twenty-four hours before the animals were subjected to brain ischemia, a whole caudal blood sample of 200 μL was withdrawn, allowed to clot at 37°C for 2 hours, extruded from the catheter into a saline-filled petri dish, and stored at 4°C for 22 hours before being used the day after to induce thromboembolic ischemia.…”