A possible effect of the methylxanthines caffeine, theophylline and aminophylline on postnatal myelination of the rat brain.

A double isotope methodology was used to assess the effect of methylxanthine administration on membrane protein synthesis in developing rat brain. Rat pups were given either aminophylline, theophylline, or caffeine in a dosage of 40 mg/kg or 80 mg/kg daily from the second postnatal day through 20 days of age. Results show depressed myelin protein synthesis at 21.24 days by theophylline (80 mg/kg) and caffeine (40 and 80 mg/kg). Synthesis was essentially normal at 27-28 days of age, indicating a possible delay in development followed by a 'catch-up' phenomenon.