Abstract
The distribution of several compounds between blood, and brain and cerebrospinal fluid has been studied in the five vertebrate classes. Throughout the vertebrates there is uniformity in that the steady state ratio between brain and plasma (RB) was low (<0.20) for sulfanilic acid. RB was in all instances approximately unity for sulfanilamide and was consistently greater than one for ascorbic acid. In the frog and dog steady state ratios between CSF and plasma (RCSF) closely followed the ratios for brain.
In fish (cyclostome, elasmobranch and marine telcost) extradural fluid-plasma distribution ratios (REDF) approached unity for all compounds Studied.
Comparative rate studies on transfer of sulfadiazine, sulfanilic acid and antipyrine into brain, ventricular fluid and EDF of the dogfish showed similar rate constants for brain and ventricular fluid. The transfer of these drugs was much less rapid into EDF.
The fluid surrounding dogfish brain (EDF) has a significant protein content, and these proteins are identical with the plasma proteins of this species.
Footnotes
- Received October 9, 1958.
JPET articles become freely available 12 months after publication, and remain freely available for 5 years.Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page.
|