When two different chemical act on two different receptors and their responses is opposite to each other on the same cell is called as ?
**Core Concept**
In pharmacology, the concept being tested here is the interaction between two different chemical agents acting on distinct receptors on the same cell, resulting in opposite responses. This phenomenon is a fundamental aspect of cellular physiology, where the action of one agonist can be modulated by another agonist or antagonist.
**Why the Correct Answer is Right**
The correct answer describes a situation where two different chemical agents act on two different receptors on the same cell, producing opposite responses. This can occur through various mechanisms, such as competitive antagonism, where one agonist binds to a receptor and reduces the binding affinity of another agonist. Alternatively, it can occur through non-competitive antagonism, where one agonist binds to a receptor and reduces the receptor's ability to respond to another agonist. In both cases, the response of the cell to the second agonist can be diminished or reversed.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the concept being tested, as it describes a situation where two different chemical agents act on the same receptor, producing different responses. However, this scenario does not necessarily involve opposite responses on the same cell.
**Option B:** This option is incorrect because it describes a situation where two different chemical agents act on the same receptor, producing opposite responses. However, this scenario does not necessarily involve two different receptors on the same cell.
**Option C:** This option is incorrect because it describes a situation where two different chemical agents act on distinct receptors, producing synergistic responses. However, the question specifically asks for a situation where the responses are opposite to each other.
**Clinical Pearl / High-Yield Fact**
An important concept to remember is that the response of a cell to two different chemical agents can be modulated by their interaction at the receptor level. This can lead to complex pharmacological interactions, where the effect of one drug can be influenced by another drug.
**Correct Answer: C. Paradoxical effect**