Leucocyte Membrane Determinants Regulating Immune Reactivity

per hour elevates serum ascorbate from about 1 mg/dl to a maximum of 4 mg/dl. Again, the physiological significance of Lewin's observation is questionable. After stress or ACTH secretion, adrenocorticosteroid secretion is associated with decreased adrenal cholesterol and ascorbate. From this finding, Lewin hypothesizes that vitamin C plays an important role in the synthesis of adrenal steroids. He does not, however, satisfactorily address the observations that adrenocorticosteroid secretion is normal in scorbutic individuals and that steroid secretion in perfused adrenal glands is not affected by the concentration of vitamin C in the perfusate. One should look elsewhere for a critical review of the biological actions and potential medical value of vitamin C. Eiuc J. NESTLER Medical Student Yale University School ofMedicine