RT Journal Article
SR Electronic
T1 THE EFFECTS OF CARBON DIOXIDE ON THE ENTRY AND ACCUMULATION OF DRUGS IN THE CENTRAL NERVOUS SYSTEM
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 308
OP 318
VO 131
IS 3
A1 Mark A. Goldberug
A1 Charles F. Barlow
A1 Lloyd J. Roth
YR 1961
UL http://jpet.aspetjournals.org/content/131/3/308.abstract
AB Exposurre to 25% carbons dioxide increased the concentration of phenobarbital, salicylic acid, acetazolamide and urea in all anatomical regions of the cat brain. Conversely, brain levels of all of thsese substances were reduced by hyperventilation. High concentrations of carbon dioxide produced a greater relative increase in the entry and accumulation of salicylic acid, phenobarbital and acetazolamide in predominantly myelinated areas than in gray matter. Hyperventilation produced the opposite effects. These findings are discussed in relation to the anatomical structure of myelin and changes in the dissociation of organic electrolytes. Urea, a non-electrolyte, did not exhibit any correlation between blood pH and concentration in different brain regions. The change in urea penetration suggests that carbon dioxide has a significant and perhaps unique effect on the entry of materials into the brain. The effect of changes in blood flow and tissue binding on these results is also discussed.