A research scientist develops an agent that specifically blocks the interaction of inositol triphosphate with its intracellular receptor. A study is then performed in which vascular smooth muscle cells are divided into 2 groups: an experimental group treated with the receptor blocker and an untreated control group. Both groups are exposed to phenylephrine. Compared to the control cells, decreased activity of which of the following enzymes is most likely to be observed in the experimental cells?

Question

A research scientist develops an agent that specifically blocks the interaction of inositol triphosphate with its intracellular receptor.  A study is then performed in which vascular smooth muscle cells are divided into 2 groups: an experimental group treated with the receptor blocker and an untreated control group.  Both groups are exposed to phenylephrine.  Compared to the control cells, decreased activity of which of the following enzymes is most likely to be observed in the experimental cells?

Quizplus · Accepted Answer

Eductional Objective: After a ligand binds to a G protein-coupled receptor that activates phospholipase C, membrane phospholipids are broken down into diacylglycerol (DAG) and inositol triphosphate (IP₃). Protein kinase C is subsequently activated by DAG and calcium; the latter is released from the endoplasmic reticulum under the influence of IP₃

A Research Scientist Develops an Agent That Specifically Blocks the Interaction