Phosphoinositide Signal Transduction System in Postmortem Human Brain
The phosphoinositide signal transduction system is one of the major receptor-coupled second messenger-producing intracellular signaling systems in the brain. At its most basic level, this signaling system consists of receptors, heterotrimeric G-proteins, and phospholipase C, and it contributes a critical component to a cell’s regulation of intracellular calcium levels and activities of protein kinases. Phosphoinositide signaling has been assessed in postmortem brain using membrane preparations incubated with selective stimulatory agents. Membranes are incubated with radiolabeled phosphoinositides and receptor agonists to measure receptor-coupled signaling, with activators of G-proteins to measure G-protein-coupled signaling, and with added calcium to directly stimulate phospholipase C activity. These measurements along with a variety of other techniques have proven useful for assessing the activities of the major protein components of the phosphoinositide signaling system in postmortem brain obtained from subjects with a variety of diseases.
KeywordsMuscarinic Receptor Postmortem Brain Bipolar Affective Disorder Suicide Victim Postmortem Human Brain
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