A 27-year-old woman presents with infertility, oligomenorrhea, and galactorrhea. Vital signs: BP 118/76, HR 88, RR 16, Temp 37°C. Laboratory evaluation reveals serum prolactin 85 ng/mL (normal <25). Thyroid-stimulating hormone and free T4 are normal. Pituitary MRI shows a 8-mm sellar mass without mass effect. She denies antipsychotic or metoclopramide use. Which hypothalamic factor normally tonically inhibits prolactin secretion?
- A)Thyrotropin releasing hormone
- B)Corticotropin releasing hormone
- C)Somatostatin
- D)Growth hormone releasing hormone
- E)DopamineGABARITO
Explicação
Dopamine from the hypothalamus tonically inhibits prolactin secretion by anterior pituitary lactotrophs. Loss of this inhibitory input, whether from stalk compression or dopamine antagonists, causes hyperprolactinemia with infertility and menstrual dysfunction... Ver explicação completa e trilha adaptativa →