Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Br J Pharmacol
2002 Jan 01;1352:427-32. doi: 10.1038/sj.bjp.0704496.
Show Gene links
Show Anatomy links
The beta-lactam antibiotics, penicillin-G and cefoselis have different mechanisms and sites of action at GABA(A) receptors.
Sugimoto M, Fukami S, Kayakiri H, Yamazaki S, Matsuoka N, Uchida I, Mashimo T.
???displayArticle.abstract???
The action of the beta-lactam antibiotics, penicillin-G (PCG) and cefoselis (CFSL) on GABA(A) receptors (GABA(A)-R) was investigated using the two-electrode voltage clamp technique and Xenopus oocyte expressed murine GABA(A)-R. Murine GABA(A)-Rs were expressed in Xenopus oocytes by injecting cRNA that encoded for each subunit (alpha1, beta2, and gamma2) and the effects of PCG and CFSL on the alpha1beta2gamma2s subunit receptors were examined using two-electrode voltage clamp. Using the alpha1beta2gamma2s GABA(A)-R, PCG and CFSL inhibited GABA-induced currents in a concentration-dependent manner, with IC(50)s of 557.1+/-125.4 and 185.0+/-26.6 microM, respectively. The inhibitory action of PCG on GABA-induced currents was non-competitive whereas that of CFSL was competitive. Mutation of tyrosine to phenylalanine at position 256 in the beta2 subunit (beta2(Y256F)), which is reported to abolish the inhibitory effect of picrotoxin, drastically reduced the potency of PCG (IC(50)=28.4+/-1.42 mM) for the alpha1beta2(Y256F)gamma2s receptor without changing the IC(50) of CFSL (189+/-26.6 microM). These electrophysiological data indicate that PCG and CFSL inhibit GABA(A)-R in a different manner, with PCG acting non-competitively and CFSL competitively. The mutational study indicates that PCG might act on an identical or nearby site to that of picrotoxin in the channel pore of the GABA(A)-R.
Barnard,
International Union of Pharmacology. XV. Subtypes of gamma-aminobutyric acidA receptors: classification on the basis of subunit structure and receptor function.
1998, Pubmed
Barnard,
International Union of Pharmacology. XV. Subtypes of gamma-aminobutyric acidA receptors: classification on the basis of subunit structure and receptor function.
1998,
Pubmed Barrons,
Populations at risk for penicillin-induced seizures.
1992,
Pubmed Curtis,
Convulsive action of penicillin.
1972,
Pubmed Franks,
Molecular and cellular mechanisms of general anaesthesia.
1994,
Pubmed Fujimoto,
Dual mechanisms of GABAA response inhibition by beta-lactam antibiotics in the pyramidal neurones of the rat cerebral cortex.
1995,
Pubmed Gurley,
Point mutations in the M2 region of the alpha, beta, or gamma subunit of the GABAA channel that abolish block by picrotoxin.
1995,
Pubmed
,
Xenbase Hori,
Inhibitory effect of cephalosporins on gamma-aminobutyric acid receptor binding in rat synaptic membranes.
1985,
Pubmed Mine,
In vitro antibacterial activity of FK037, a novel parenteral broad-spectrum cephalosporin.
1993,
Pubmed Mine,
In vivo antibacterial activity of FK037, a novel parenteral broad-spectrum cephalosporin.
1993,
Pubmed Pickles,
Antagonism by penicillin of gamma-aminobutyric acid depolarizations at presynaptic sites in rat olfactory cortex and cuneate nucleus in vitro.
1980,
Pubmed Sieghart,
Structure and pharmacology of gamma-aminobutyric acidA receptor subtypes.
1995,
Pubmed Tsuda,
Effect of penicillin on GABA-gated chloride ion influx.
1994,
Pubmed Twyman,
Kinetics of open channel block by penicillin of single GABAA receptor channels from mouse spinal cord neurones in culture.
1992,
Pubmed Verdoorn,
Functional properties of recombinant rat GABAA receptors depend upon subunit composition.
1990,
Pubmed Wallace,
Antibiotic-induced convulsions.
1997,
Pubmed WEINSTEIN,
CLINICAL AND BACTERIOLOGIC STUDIES OF THE EFFECT OF "MASSIVE" DOSES OF PENICILLIN G ON INFECTIONS CAUSED BY GRAM-NEGATIVE BACILLI.
1964,
Pubmed Whiting,
Structure and pharmacology of vertebrate GABAA receptor subtypes.
1995,
Pubmed Zeng,
Inhibitory influence of morphinans on ictal and interictal EEG changes induced by cortical application of penicillin in rabbits: a comparative study with NMDA antagonists and pentobarbitone.
1992,
Pubmed