The behavior of muscle membrane treated with a trace metal chelating agent

✍ Scribed by Jenerick, Howard

• Publisher: Wiley (John Wiley & Sons)
• Year: 1959
• Tongue: English
• Weight: 970 KB
• Volume: 53
• Category: Article
• ISSN: 0095-9898
• DOI: 10.1002/jcp.1030530302

✦ Synopsis

Cupferron (a chelating agent for heavy metals) can block conduction in a mixed nerve (frog sciatic) without greatly increasing thresholds or depolarizing the injury potential (Jenerick, '57a). This seemed to rule out anesthesia or metabolic inhibition as the primary cause of the conduction block. One of the explanations offered at that time f o r these results was that cupferron inhibits the mechanism underlying the action potential. To test this hypothesis the blocking properties of cupferron were studied using single cells. The sartorius muscle fiber is eminently suitable for transmembrane stimulation and recording techniques. The present re- sults suggest that cupferron interferes with the sodium current during the action potential in addition to inhibiting metabolism and depolarizing the resting potential by independent means.

Methods

Sartorius muscle was obtained by dissection from Ranu pipiens. The Ringer's fluid, aerated before use, was usually composed of 111 mM NaC1, 2.5 mM KCl, 4 mM CaCl,, and