A 66-Year-Old Man with Hypertension and Stage IV Chronic Kidney

question 253

Multiple Choice

A 66-year-old man with hypertension and stage IV chronic kidney disease comes to the office for follow-up.  The patient has had worsened fatigue and low energy over the past several months but no chest pain or shortness of breath.  He was previously nonadherent with antihypertensive therapy but has been following treatment recommendations since renal dysfunction was diagnosed 2 years ago.  Blood pressure is 126/78 mm Hg and pulse is 68/min.  Cardiac auscultation reveals an S4 sound.  The rest of the physical examination is unremarkable.  Laboratory results show normocytic, normochromic anemia with a low reticulocyte count.  Serum iron studies are within normal limits.  Treatment with a recombinant glycoprotein hormone is begun, and repeat laboratory testing several weeks later shows an improvement in hemoglobin level.  The effects of the hormone prescribed for this patient are most likely mediated by which of the following pathways?

• A)Adenylate cyclase/cyclic AMP
• B)Arachidonic acid/phospholipase A2
• C)Janus kinase 2/signal transducers and activators of transcription
• D)Nuclear receptors
• E)Phosphatidylinositol 3-kinase
• F)Ras/mitogen-activated protein kinase