Transport of an antihypoxic drug stobadine across the blood-brain barrier in rat striatum and its influence on catecholamine-oxidative current: a voltammetric study under normal and anoxic/ischaemic conditions.
Differential pulse voltammetry with a carbon fibre microelectrode (ME) was used in pentobarbital-anaesthetized rats for monitoring the stobadine current (STB.C) on both sides of the blood-brain barrier (BBB) in the arterial bloodstream (BS) and in the corpus striatum (CS). The STB.C exhibited a distinct peak at a polarization voltage 540 +/- 30 mV (n = 4). The maximum of STB.C in BS attained 2-3 min after the STB administration (2.8 mg/100 g in 1.0 ml saline solution i.a.) was followed by a rapid decrease to about 20% within next 3 min. The STB readily passed across the BBB: the STB.C peak appeared in the CS in the 3rd minute and continued to rise up to the 30th min. The administration of STB did not prevent a large increase (1347 +/- 326%, n = 3) of the catechol-oxidative current (CA.OC) occurring in the CS between the 4th and 5th minute after cardiac arrest. However, a decrease of ME sensitivity to CA.OC in the presence of STB was observed. This fact leads to the speculation whether a similar "quenching" of dopamine by STB could not participate in the protective effects of STB observed in the brain exposed to hypoxia-reoxygenation.
Pavlásek
J
J
Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Bratislava, Slovak Republic.
Haburcák
M
M
Masánová
C
C
Stolc
S
S
D000818:Animals; D001692:Biological Transport; D001812:Blood-Brain Barrier / Q000502:physiology*; D002545:Brain Ischemia / Q000378:metabolism*; D002243:Carbolines / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology*; D002395:Catecholamines / Q000032:analysis / Q000378:metabolism*; D003342:Corpus Striatum / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism / Q000494:pharmacology; D004594:Electrophysiology; D002534:Hypoxia, Brain / Q000378:metabolism*; D008297:Male; D008839:Microelectrodes; D010084:Oxidation-Reduction; D051381:Rats; D017208:Rats, Wistar
D002243:Carbolines; D002395:Catecholamines; D004298:Dopamine; C100106:dicarbine