What is the G protein associated with D1 receptors, and what is the resultant second messenger?

D1 receptors are a type of dopamine receptor that primarily functions through the Gs protein. The Gs protein, when activated, stimulates adenylyl cyclase, which leads to an increase in the production of cyclic AMP (cAMP) from ATP. This increase in cAMP serves as a second messenger that activates protein kinase A (PKA), subsequently influencing various intracellular signaling pathways that can affect neuronal function and other physiological processes.

The role of D1 receptors is particularly significant in the central nervous system where they facilitate dopaminergic signaling, contributing to behaviors and motor control. The activation of Gs and the increase of cAMP promotes various downstream effects, which can have implications in conditions such as Parkinson's disease where dopaminergic signaling is disrupted.

While other G proteins and their associated pathways are important in different contexts, the association of D1 receptors with Gs protein and the resultant increase in cAMP is a fundamental aspect of their biological function.