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A. De Sarro - One of the best experts on this subject based on the ideXlab platform.

  • Effects of some excitatory amino acid antagonists on imipenem-induced seizures in DBA/2 mice
    Brain research, 1995
    Co-Authors: G. De Sarro, D. Ammendola, Felice Nava, A. De Sarro
    Abstract:

    Abstract The behavioural and convulsant effects of imipenem (Imi), a Carbapenem Derivative, were studied after intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures. The anticonvulsant effects of some excitatory amino acid antagonists and muscimol (Msc), a GABA A agonist, against seizures induced by i.p. or i.c.v. administration of Imi were also evaluated. The present study demonstrated that the order of anticonvulsant activity in our epileptic model, after i.p. administration, was (+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)-cyclohepten-5,10-imine maleate (MK-801) > (±)(E)-2-amino-4-methyl-5-phosphono-3-pentenoate ethyl ester (CGP 39551) > 3-((±)-2-carboxypiperazin-4-yl)propenyl-1-phosphonic acid (CPPene) . 3-((±)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CCP) > 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(F)-quinoxaline (NBQX). Ifenprodil, a compound acting on the polyamine site of NMDA receptor complex was unable to protect against seizures induced by Imi, suggesting that the poliamine site did not exert a principal role in the genesis of seizures induced by Imi. In addition, the order of anticonvulsant potency in our epileptic model, after i.c.v. administration, was CPPene > MK-801 ? Msc ? (−)-2-amino-7-phosphonic acid (AP7) > γ-D-glutamylaminomethylsulphonate (γ-D-GAMS) > NBQX > kynurenic acid (KYNA) > 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX). The relationship between the different site of action and the anticonvulsant activity of these Derivatives was discussed. Although the main mechanism of Imi induced seizures cannot be easily determined, potential interactions with the receptors of the excitatory amino acid neurotransmitters exists. In fact, antagonists of excitatory amino acids are able to increase the threshold for the seizures or to prevent the seizures induced by Imi. In addition, Imi acts on the central nervous system by inhibition of GABA neurotransmission and Msc, a selective GABA A agonist, was able to protect against seizures induced by Imi.

  • Effects of some quinolones on imipenem-induced seizures in DBA/2 mice
    General pharmacology, 1994
    Co-Authors: A. De Sarro, D. Ammendola, G. De Sarro
    Abstract:

    Abstract 1. The behavioural and convulsant effects of imipenem, a Carbapenem Derivative, were studied after i.p. administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures and in Swiss mice. 2. It was found that DBA/2 mice were more susceptible to seizures induced by imipenem than Swiss mice. 3. The proconvulsant effects of some quinolones were also evaluated in DBA/2 mice on seizures evoked by means of i.p. administration of imipenem. The present study demonstrated that the order of proconvulsant activity in our epileptic model was pefloxacin > enoxacin > ofloxacin > nalidixic acid > rufloxacin > norfloxacin > ciprofloxacin > cinoxacin > temafloxacin. 4. The relationship between the chemical structure and the proconvulsant activity of quinolone Derivatives was studied. The relationship between the lipophilicity and the proconvulsant activity was also investigated. 5. Although the main mechanism for seizure potentiation cannot be easily determined potential drug interactions exist. It has been reported that imipenem and quinolones are all believed to increase excitation of the central nervous system by inhibition of GABA binding to receptors. 6. A slow clearance from the central nervous system and from the kidney may also occur following the concomitant administration of some quinolones and imipenem.

G. De Sarro - One of the best experts on this subject based on the ideXlab platform.

  • Effects of some excitatory amino acid antagonists on imipenem-induced seizures in DBA/2 mice
    Brain research, 1995
    Co-Authors: G. De Sarro, D. Ammendola, Felice Nava, A. De Sarro
    Abstract:

    Abstract The behavioural and convulsant effects of imipenem (Imi), a Carbapenem Derivative, were studied after intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures. The anticonvulsant effects of some excitatory amino acid antagonists and muscimol (Msc), a GABA A agonist, against seizures induced by i.p. or i.c.v. administration of Imi were also evaluated. The present study demonstrated that the order of anticonvulsant activity in our epileptic model, after i.p. administration, was (+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)-cyclohepten-5,10-imine maleate (MK-801) > (±)(E)-2-amino-4-methyl-5-phosphono-3-pentenoate ethyl ester (CGP 39551) > 3-((±)-2-carboxypiperazin-4-yl)propenyl-1-phosphonic acid (CPPene) . 3-((±)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CCP) > 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(F)-quinoxaline (NBQX). Ifenprodil, a compound acting on the polyamine site of NMDA receptor complex was unable to protect against seizures induced by Imi, suggesting that the poliamine site did not exert a principal role in the genesis of seizures induced by Imi. In addition, the order of anticonvulsant potency in our epileptic model, after i.c.v. administration, was CPPene > MK-801 ? Msc ? (−)-2-amino-7-phosphonic acid (AP7) > γ-D-glutamylaminomethylsulphonate (γ-D-GAMS) > NBQX > kynurenic acid (KYNA) > 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX). The relationship between the different site of action and the anticonvulsant activity of these Derivatives was discussed. Although the main mechanism of Imi induced seizures cannot be easily determined, potential interactions with the receptors of the excitatory amino acid neurotransmitters exists. In fact, antagonists of excitatory amino acids are able to increase the threshold for the seizures or to prevent the seizures induced by Imi. In addition, Imi acts on the central nervous system by inhibition of GABA neurotransmission and Msc, a selective GABA A agonist, was able to protect against seizures induced by Imi.

  • Effects of some quinolones on imipenem-induced seizures in DBA/2 mice
    General pharmacology, 1994
    Co-Authors: A. De Sarro, D. Ammendola, G. De Sarro
    Abstract:

    Abstract 1. The behavioural and convulsant effects of imipenem, a Carbapenem Derivative, were studied after i.p. administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures and in Swiss mice. 2. It was found that DBA/2 mice were more susceptible to seizures induced by imipenem than Swiss mice. 3. The proconvulsant effects of some quinolones were also evaluated in DBA/2 mice on seizures evoked by means of i.p. administration of imipenem. The present study demonstrated that the order of proconvulsant activity in our epileptic model was pefloxacin > enoxacin > ofloxacin > nalidixic acid > rufloxacin > norfloxacin > ciprofloxacin > cinoxacin > temafloxacin. 4. The relationship between the chemical structure and the proconvulsant activity of quinolone Derivatives was studied. The relationship between the lipophilicity and the proconvulsant activity was also investigated. 5. Although the main mechanism for seizure potentiation cannot be easily determined potential drug interactions exist. It has been reported that imipenem and quinolones are all believed to increase excitation of the central nervous system by inhibition of GABA binding to receptors. 6. A slow clearance from the central nervous system and from the kidney may also occur following the concomitant administration of some quinolones and imipenem.

Daniel P. Bonner - One of the best experts on this subject based on the ideXlab platform.

  • Structure-activity relationships of Carbapenems that determine their dependence on porin protein D2 for activity against Pseudomonas aeruginosa.
    Antimicrobial agents and chemotherapy, 1995
    Co-Authors: Joan Fung-tomc, E Huczko, J Banville, Marcel Menard, B Kolek, Elizabeth Gradelski, R E Kessler, Daniel P. Bonner
    Abstract:

    A number of Carbapenem Derivatives were examined to determine the structure-activity relationships required for dependence on porin protein D2 for activity against Pseudomonas aeruginosa. As suggested by J. Trias and H. Nikaido (Antimicrob. Agents Chemother. 34:52-57, 1990), Carbapenem Derivatives, such as imipenem and meropenem, containing a sole basic group at position 2 of the molecule utilize the D2 channel for permeation through the outer membrane of pseudomonads; they are more active against D2-sufficient strains of P. aeruginosa. Our results indicated that Carbapenems with a basic group at position 1 or 6 of the molecule did not depend on the D2 channel for activity; i.e. they were equally active against D2-sufficient and D2-deficient pseudomonal strains. However, addition of a basic group at position 1 or 6 of a Carbapenem Derivative already containing a basic group at position 2 resulted in its lack of dependency on the D2 pathway. Comparison between meropenem and its 1-guanidinoethyl Derivative, BMY 45047, indicated that they differed in their dependence on D2; while meropenem required the D2 channel for uptake, BMY 45047 activity was independent of D2. Meropenem and BMY 45047 had similar affinities for the penicillin-binding proteins of P. aeruginosa. However, BMY 45047 and meropenem differed in the morphological changes that they induced in pseudomonal cells. While meropenem induced filamentation, BMY 45047 induced filaments only in BMS-181139-resistant mutants and not in imipenem-resistant mutants or in Carbapenem-susceptible P. aeruginosa strains. These results suggested that in Mueller-Hinton medium the uptake of BMY 45047 through the non-D2 pathway is more rapid than that of meropenem through the D2 porin. In summary, the presence of a basic group at position 2 of a Carbapenem is important for its preferential uptake by the D2 channel. However the addition of a basic group at position 1 or 6 of a Carbapenem already containing a basic group at position 2 dissociates its necessity for porin protein D2 for activity.

D. Ammendola - One of the best experts on this subject based on the ideXlab platform.

  • Effects of some excitatory amino acid antagonists on imipenem-induced seizures in DBA/2 mice
    Brain research, 1995
    Co-Authors: G. De Sarro, D. Ammendola, Felice Nava, A. De Sarro
    Abstract:

    Abstract The behavioural and convulsant effects of imipenem (Imi), a Carbapenem Derivative, were studied after intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures. The anticonvulsant effects of some excitatory amino acid antagonists and muscimol (Msc), a GABA A agonist, against seizures induced by i.p. or i.c.v. administration of Imi were also evaluated. The present study demonstrated that the order of anticonvulsant activity in our epileptic model, after i.p. administration, was (+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)-cyclohepten-5,10-imine maleate (MK-801) > (±)(E)-2-amino-4-methyl-5-phosphono-3-pentenoate ethyl ester (CGP 39551) > 3-((±)-2-carboxypiperazin-4-yl)propenyl-1-phosphonic acid (CPPene) . 3-((±)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CCP) > 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(F)-quinoxaline (NBQX). Ifenprodil, a compound acting on the polyamine site of NMDA receptor complex was unable to protect against seizures induced by Imi, suggesting that the poliamine site did not exert a principal role in the genesis of seizures induced by Imi. In addition, the order of anticonvulsant potency in our epileptic model, after i.c.v. administration, was CPPene > MK-801 ? Msc ? (−)-2-amino-7-phosphonic acid (AP7) > γ-D-glutamylaminomethylsulphonate (γ-D-GAMS) > NBQX > kynurenic acid (KYNA) > 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX). The relationship between the different site of action and the anticonvulsant activity of these Derivatives was discussed. Although the main mechanism of Imi induced seizures cannot be easily determined, potential interactions with the receptors of the excitatory amino acid neurotransmitters exists. In fact, antagonists of excitatory amino acids are able to increase the threshold for the seizures or to prevent the seizures induced by Imi. In addition, Imi acts on the central nervous system by inhibition of GABA neurotransmission and Msc, a selective GABA A agonist, was able to protect against seizures induced by Imi.

  • Effects of some quinolones on imipenem-induced seizures in DBA/2 mice
    General pharmacology, 1994
    Co-Authors: A. De Sarro, D. Ammendola, G. De Sarro
    Abstract:

    Abstract 1. The behavioural and convulsant effects of imipenem, a Carbapenem Derivative, were studied after i.p. administration in DBA/2 mice, a strain genetically susceptible to sound-induced seizures and in Swiss mice. 2. It was found that DBA/2 mice were more susceptible to seizures induced by imipenem than Swiss mice. 3. The proconvulsant effects of some quinolones were also evaluated in DBA/2 mice on seizures evoked by means of i.p. administration of imipenem. The present study demonstrated that the order of proconvulsant activity in our epileptic model was pefloxacin > enoxacin > ofloxacin > nalidixic acid > rufloxacin > norfloxacin > ciprofloxacin > cinoxacin > temafloxacin. 4. The relationship between the chemical structure and the proconvulsant activity of quinolone Derivatives was studied. The relationship between the lipophilicity and the proconvulsant activity was also investigated. 5. Although the main mechanism for seizure potentiation cannot be easily determined potential drug interactions exist. It has been reported that imipenem and quinolones are all believed to increase excitation of the central nervous system by inhibition of GABA binding to receptors. 6. A slow clearance from the central nervous system and from the kidney may also occur following the concomitant administration of some quinolones and imipenem.

Joan Fung-tomc - One of the best experts on this subject based on the ideXlab platform.

  • Structure-activity relationships of Carbapenems that determine their dependence on porin protein D2 for activity against Pseudomonas aeruginosa.
    Antimicrobial agents and chemotherapy, 1995
    Co-Authors: Joan Fung-tomc, E Huczko, J Banville, Marcel Menard, B Kolek, Elizabeth Gradelski, R E Kessler, Daniel P. Bonner
    Abstract:

    A number of Carbapenem Derivatives were examined to determine the structure-activity relationships required for dependence on porin protein D2 for activity against Pseudomonas aeruginosa. As suggested by J. Trias and H. Nikaido (Antimicrob. Agents Chemother. 34:52-57, 1990), Carbapenem Derivatives, such as imipenem and meropenem, containing a sole basic group at position 2 of the molecule utilize the D2 channel for permeation through the outer membrane of pseudomonads; they are more active against D2-sufficient strains of P. aeruginosa. Our results indicated that Carbapenems with a basic group at position 1 or 6 of the molecule did not depend on the D2 channel for activity; i.e. they were equally active against D2-sufficient and D2-deficient pseudomonal strains. However, addition of a basic group at position 1 or 6 of a Carbapenem Derivative already containing a basic group at position 2 resulted in its lack of dependency on the D2 pathway. Comparison between meropenem and its 1-guanidinoethyl Derivative, BMY 45047, indicated that they differed in their dependence on D2; while meropenem required the D2 channel for uptake, BMY 45047 activity was independent of D2. Meropenem and BMY 45047 had similar affinities for the penicillin-binding proteins of P. aeruginosa. However, BMY 45047 and meropenem differed in the morphological changes that they induced in pseudomonal cells. While meropenem induced filamentation, BMY 45047 induced filaments only in BMS-181139-resistant mutants and not in imipenem-resistant mutants or in Carbapenem-susceptible P. aeruginosa strains. These results suggested that in Mueller-Hinton medium the uptake of BMY 45047 through the non-D2 pathway is more rapid than that of meropenem through the D2 porin. In summary, the presence of a basic group at position 2 of a Carbapenem is important for its preferential uptake by the D2 channel. However the addition of a basic group at position 1 or 6 of a Carbapenem already containing a basic group at position 2 dissociates its necessity for porin protein D2 for activity.