Prolactin controlling agent is

Options

A. Ach
B. Dopamine
C. GABA
D. Prostaglandins

Answer

**Step-by-Step Solution:**

1. **Understanding Prolactin**: Prolactin is a hormone primarily responsible for stimulating milk production in mammals. It is secreted by the anterior pituitary gland.

2. **Identifying Controlling Agents**: The secretion of prolactin is regulated by various factors, including hormones and neurotransmitters.

3. **Role of Dopamine**: Among the options provided, dopamine is known to be a major prolactin inhibiting factor. It is produced in the hypothalamus and released into the portal circulation.

4. **Mechanism of Action**: Dopamine binds to specific receptors on lactotroph cells in the anterior pituitary gland. This binding inhibits both the synthesis and secretion of prolactin.

5. **Conclusion**: Based on the information, we can conclude that the controlling agent for prolactin is dopamine.

**Final Answer**: The prolactin controlling agent is **dopamine** (Option 2).

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