Ch 18 Flashcards
A neuroscientist is studying communication between the hypothalamus and pituitary in a rat model. She interrupts blood flow through the median eminence and then measures circulating levels of pituitary hormones following appropriate physiologic stimulation. Secretion of which of the following hormones will be unaffected by the experimental manipulation? A. Growth hormone B. Prolactin C. Thyroid-stimulating hormone D. Follicle-stimulating hormone E. Vasopressin
E. Vasopressin
Which of the following pituitary hormones is an opioid peptide?
A. α-Melanocyte-stimulating hormone (α-MSH) B. β-MSH
C. ACTH
D. Growth hormone
E. β-Endorphin
E. β-Endorphin
During childbirth, a woman suffers a serious hemorrhage and goes into shock. After she recovers, she displays symptoms of hypopituitarism. Which of the following will not be expected in this patient? A. Cachexia B. Infertility C. Pallor D. Low basal metabolic rate E. Intolerance to stress
A. Cachexia
A scientist finds that infusion of growth hormone into the median eminence of the hypothalamus in experimental animals inhibits the secretion of growth hormone and concludes that this proves that growth hormone feeds back to inhibit GHRH secretion. Do you accept this conclusion?
A. No, because growth hormone does not cross the blood-brain barrier.
B. No, because the infused growth hormone could be stimulating dopamine secretion.
C. No, because substances placed in the median eminence could be transported to the anterior pituitary.
D. Yes, because systemically administered growth hormone inhibits growth hormone secretion.
E. Yes, because growth hormone binds GHRH, inactivating it.
C. No, because substances placed in the median eminence could be transported to the anterior pituitary.
The growth hormone receptor
A. activates Gs.
B. requires dimerization to exert its effects.
C. must be internalized to exert its effects.
D. resembles the IGF-I receptor.
E. resembles the ACTH receptor.
B. requires dimerization to exert its effects.
