Quick revision: every question with its correct answer. For the full explanation, open the test and tap View Solution.
4.4 Prolactin — Test 1
Q1. Prolactin secretion is tonically INHIBITED by:✓ Dopamine (prolactin-inhibiting factor)
Q2. The major physiological action of prolactin is:✓ Stimulation of milk production (lactogenesis)
Q3. A prolactin-secreting tumour (prolactinoma) typically causes:✓ Galactorrhoea and amenorrhoea (with decreased libido)
Q4. Bromocriptine reduces prolactin secretion because it acts as a:✓ Dopamine agonist
Q5. Excess prolactin causes amenorrhoea and failure to ovulate mainly because it:✓ Inhibits GnRH secretion
Q6. Which factor INCREASES prolactin secretion?✓ TRH
Q7. Match each agent with its effect on prolactin and choose the correct option.✓ A-ii, B-i, C-iii
Q8. Prolactin inhibits its own secretion by:✓ Stimulating hypothalamic dopamine release (short-loop feedback)
Q9. The lactogenic hormone among the following is:✓ Luteotropin (prolactin)
Q10. Why does lactation NOT occur during pregnancy despite high prolactin?✓ High estrogen and progesterone block prolactin's action on the breast
Q11. Prolactin deficiency (e.g. after pituitary destruction) results in:✓ Failure to lactate
Q12. A man with galactorrhoea is found to have a prolactinoma. Bromocriptine helps because it:✓ Inhibits prolactin release from the anterior pituitary
Q13. Suckling maintains lactation because it stimulates secretion of:✓ Both prolactin and oxytocin
Q14. Hyperprolactinaemia can result from drugs that are:✓ Dopamine antagonists (e.g. some antipsychotics)
Q15. Prolactin is structurally homologous to:✓ Growth hormone and human placental lactogen
Q16. During lactation, ovulation is often suppressed because prolactin:✓ Inhibits GnRH and the action of LH/FSH on the ovary
Q17. The prolactin receptor belongs to the same family as the receptor for:✓ Growth hormone (JAK-STAT cytokine receptor)
Q18. In a patient with a non-functioning pituitary mass compressing the stalk, prolactin may be mildly elevated because:✓ Dopamine delivery to the pituitary is reduced (stalk effect)
Q19. Which combination correctly lists factors that INCREASE prolactin?✓ Estrogen, TRH, suckling, stress
Q20. The reason primary hypothyroidism can raise prolactin is that:✓ High TRH (from low thyroid hormone) stimulates prolactin