All the following agents inhibit cerebrospinal fluid production EXCEPT which one?

All the following agents inhibit cerebrospinal fluid production EXCEPT which one?

• A. Furosemide
• B. Halothane
• C. Acetazolamide
• D. Enflurane

Answer: (D)

CSF production is carried out by the choroid plexus through active transport of ions, with water following; anything that disrupts ion transport or the enzymes that support secretion can reduce CSF formation. Acetazolamide blocks carbonic anhydrase, which limits bicarbonate availability and Na+ transport into the ventricles, leading to lower CSF production. Furosemide, a loop diuretic, inhibits the Na-K-2Cl transporter in the choroid plexus, also diminishing CSF secretion. Halothane, as a volatile anesthetic, tends to suppress CSF production by reducing choroidal secretory activity in addition to its effects on cerebral blood flow and metabolism. Enflurane, however, does not significantly inhibit the CSF-secreting processes, so CSF production remains relatively unchanged with its use. Thus, the first three agents decrease CSF formation, while enflurane does not, making it the exception.

CSF production is carried out by the choroid plexus through active transport of ions, with water following; anything that disrupts ion transport or the enzymes that support secretion can reduce CSF formation. Acetazolamide blocks carbonic anhydrase, which limits bicarbonate availability and Na+ transport into the ventricles, leading to lower CSF production. Furosemide, a loop diuretic, inhibits the Na-K-2Cl transporter in the choroid plexus, also diminishing CSF secretion. Halothane, as a volatile anesthetic, tends to suppress CSF production by reducing choroidal secretory activity in addition to its effects on cerebral blood flow and metabolism. Enflurane, however, does not significantly inhibit the CSF-secreting processes, so CSF production remains relatively unchanged with its use. Thus, the first three agents decrease CSF formation, while enflurane does not, making it the exception.