Which of the following is NOT a type of receptor mentioned?

The correct answer is the option identifying Ion Selective Receptors as not a type of receptor commonly referenced in pharmacological contexts. In pharmacology, the major categories of receptors include G Protein Coupled Receptors, Ligand Gated Ion Channels, and Nuclear Receptors.

G Protein Coupled Receptors are a large family that respond to various external signals and play crucial roles in numerous physiological processes. Ligand Gated Ion Channels facilitate the passage of ions across cell membranes in response to specific stimuli, directly influencing cell signaling and activity. Nuclear Receptors, which include steroid hormone receptors, operate within the cell nucleus to regulate gene expression in response to their ligands.

Ion Selective Receptors are not typically categorized as one of the primary receptor types in pharmacology, as they refer more specifically to channels that selectively allow certain ions to pass through based on their ionic characteristics rather than functioning as signal transducers like the other types. This distinction highlights why Ion Selective Receptors do not fit into the standard descriptions of receptor types used in pharmacological discussions.