Calcium signaling and neuronal vulnerability to ischemia in the striatum.
Neurons express extremely different sensitivity to ischemic insults. The neuronal vulnerability is region-specific and the striatum is among the most susceptible areas to ischemic damage. Projecting GABAergic medium-sized neurons are very sensitive to energy metabolism impairment, whereas interneurons are selectively spared. However, the reasons for this differential vulnerability are largely unknown. Calcium ions (Ca2+) are important intracellular messengers enabling several physiological processes. However, excessive Ca2+ influx from the extracellular space or release from internal stores can elevate Ca2+ to levels that exceed the capacity of single neurons to appropriately buffer such overload. This capacity also appears to be a peculiar feature of single neuronal subtypes. This review will provide a brief survey of the ionic basis underlying the differential responses to in vitro ischemia of distinct striatal neuronal subtypes, mainly focusing on the role of Ca2+. The potential relevance of these findings in the development of therapeutic strategies for acute stroke will be discussed.
Pisani
Antonio
A
Dipartimento di Neuroscienze, Clinica Neurologica, Università di Roma Tor Vergata, Fondazione Santa Lucia, IRCCS, Rome, Italy.
Bonsi
Paola
P
Calabresi
Paolo
P
D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology; D020013:Calcium Signaling / Q000502:physiology*; D003342:Corpus Striatum / Q000378:metabolism* / Q000502:physiology; D006801:Humans; D009474:Neurons / Q000378:metabolism* / Q000473:pathology / Q000502:physiology