title: Diffusion of penicillin in agar and cerebral cortex of the rat.
abstract: The diffusion of penicillin was studied in agar gel and the cerebral cortex of the rat using pressure microinjection and ion-selective microelectrodes selective to penicillin. From the agar measurements a free diffusion coefficient for penicillin of 3.52 +/- 0.08 (mean +/- S.E.M.) X 10(-6) cm2.s-1 for 37 degrees C was determined. The tortuosity value in the cortex was 1.62 +/- 0.03 (mean +/- S.E.M.) at the same temperature implying an apparent diffusion coefficient of 1.34 +/- 0.07 (mean +/- S.E.M.) x 10(-6) cm2.s-1. This tortuosity value means that penicillin diffuses in the cortex in a similar manner to other extracellular substances. These diffusion values clarify previous estimates and permit accurate evaluation of epilepsy models based on the application of penicillin.
authors: Institut für Physiologie, Bereich Neurophysiologie, Münster, F.R.G.
authors: A
authors: A
authors: Lehmenkühler
authors: U
authors: U
authors: Kersting
authors: C
authors: C
authors: Nicholson
mesh_terms: D000362:Agar; D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism*; D004058:Diffusion; D007700:Kinetics; D008297:Male; D008959:Models, Neurological; D010400:Penicillin G / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D000362:Agar; D010400:Penicillin G