Effects of penicillin on procaine-elicited bursts of potential in central neuron of snail, Achatina fulica.
Effects of penicillin on changes in procaine-elicited bursts of potential (BoP) were studied in a central neuron (RP4) of snail, Achatina fulica Ferussac. Procaine elicited BoP in the RP4 neuron while penicillin elicited depolarization of the neuron. Penicillin decreased the BoP elicited by procaine in a concentration-dependent manner. The effect of penicillin on the procaine-elicited BoP was not altered in the preparations treated with ascorbate or L-NAME (N-nitro-L-arginine methyl ester). However, the inhibitory effect of penicillin on the procaine-elicited BoP was enhanced with a decrease in extracellular sodium ion. Sodium ion was one of the important ions contributing to the action potential of the neuron. Two-electrode voltage-clamp studies revealed that penicillin decreased the fast sodium inward current of the neuron. It is concluded that penicillin inhibited the BoP elicited by procaine and sodium ion altered the effect of penicillin on procaine-elicited BoP.
Department of Pharmacology, School of Nursing, College of Medicine, National Taiwan University, No.1, Sec.1, Jen-Ai Road, Taipei, Taiwan.
Yi-Hung
YH
Chen
Kuan-Ling
KL
Lu
Ru-Wan
RW
Hsiao
Ya-Ling
YL
Lee
Hong-Chieh
HC
Tsai
Chia Hsien
CH
Lin
Ming-Cheng
MC
Tsai
D000200:Action Potentials; D000779:Anesthetics, Local / Q000494:pharmacology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D018408:Patch-Clamp Techniques; D010406:Penicillins / Q000494:pharmacology*; D011343:Procaine / Q000494:pharmacology*; D012908:Snails / Q000187:drug effects* / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D015222:Sodium Channels / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors
D000779:Anesthetics, Local; D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D018696:Neuroprotective Agents; D010406:Penicillins; D015222:Sodium Channels; D011343:Procaine; D012964:Sodium; D019001:Nitric Oxide Synthase; D001205:Ascorbic Acid; D002118:Calcium; D019331:NG-Nitroarginine Methyl Ester