Question

\(\beta\)-endorphins are synthesized from --
(A) Gonadotpic cells of anterior lobe of adenohypophysis.
(B) Gonadotpic cells of intermediate lobe of adenohypophysis.
(C) Corticotrpic cells of anterior lobe of adenohypophysis.
(D) Corticotrpic cells of intermediate lobe of adenohypophysis.
Choose the correct answer from the options given below:

• A. (C) only.
• B. (A), and (C) only.
• C. (D) only.
• D. (C) and (D) only.

Hint:

Beta-endorphin, ACTH, and MSH are all cleaved from the same precursor molecule: Pro-opiomelanocortin (POMC).
POMC-producing cells are called corticotropes, located in both the anterior and intermediate lobes of the pituitary.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Beta-endorphin is an endogenous opioid neuropeptide that acts as a natural pain reliever and is involved in stress responses.
It is produced via the post-translational cleavage of the precursor polypeptide Pro-opiomelanocortin (POMC).

Step 2: Detailed Explanation:
POMC is synthesized in specific endocrine cell types of the pituitary gland (hypophysis):
- Corticotropic cells of the anterior lobe (C): Produce POMC, which is cleaved to yield Adrenocorticotropic Hormone (ACTH) and \(\beta\)-lipotropin. \(\beta\)-lipotropin is further processed to release \(\beta\)-endorphin.
- Melanotropic/Corticotropic cells of the intermediate lobe (D): Extensively cleave POMC to produce \(\alpha\)-MSH and \(\beta\)-endorphin.
Gonadotropic cells (A & B) produce FSH and LH, not POMC or endorphins.
Thus, both (C) and (D) are correct.

Step 3: Final Answer:
The correct option is (C) and (D) only, corresponding to option (D).