- know what a secondary messenger system is and its purpose
- know what the components of a secondary messenger system are
- know what the components of the phospholipase C mechanism are
- know which chemical messages utilize this system
This packet covers the phospholipase C secondary messenger system
Secondary messenger systems are used by chemical messenges that are unable to cross plasma membranes and interact with the inside of cells. The types of chemical messages that utilize these systems are the polar messengers (peptides, proteins, amines {except thyroid hormone}). Secondary messenger systems have these few basic components:
This mechanism consists of receptors and G proteins like the adenylyl cyclase system but that is the only realy similarity. Instead of adenylyl cyclase another enzyme called phospholipase C is activated by the dissasociated α subunit of the G protein. This also activates other secondary messenger systems within the cell as well in the following steps:
*Chemical messengers that utilize this particular system are: GnRH, TRH, GHRH, Angiotensin II, ADH, oxytocin, α¹ receptors
*Costanzo, Linda. Board Review Series: Physiology, 2nd Edition. Baltimore, Lippincott Williams & Wilkins, 1998. Print
Here is a useful link that will take you through this step by step:
Source: Mind of Aaron
This video covers the phospholipase C secondary messenger system
Source: Self made