Question

\(17\alpha, 20\beta\)-dihydroxy-4-pregnen-3-one is also known as?

• A. Maturation-inducing hormone
• B. Maturation inhibitory hormone
• C. Osmoregulatory hormone
• D. Courtship hormone

Hint:

In fish reproduction, \(17\alpha,20\beta\)-DP acts directly on the cell surface receptors of the oocyte to activate Maturation-Promoting Factor (MPF), initiating cellular division.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Oocyte maturation in teleost fish is regulated by hormonal pathways involving the hypothalamus-pituitary-gonadal axis.
The final stage of oocyte maturation is directly triggered by specific steroidal hormones.

Step 2: Detailed Explanation:
In most teleost fish, the pituitary luteinizing hormone (LH) stimulates the ovarian follicle cells to synthesize and release progestogens.
The most common steroid responsible for triggering germinal vesicle breakdown (GVBD) and final oocyte maturation is \(17\alpha, 20\beta\)-dihydroxy-4-pregnen-3-one (\(17\alpha, 20\beta\)-DP).
Therefore, it is commonly referred to as the Maturation-Inducing Hormone (MIH) or Maturation-Inducing Steroid (MIS).

Step 3: Final Answer:
The hormone \(17\alpha, 20\beta\)-DP is also known as the maturation-inducing hormone.