The effects of essential oil of Mentha x villosa on skeletal muscle of the toad

✍ Scribed by R. T. H. Fogaça; A. D. A. Cavalcante; A. K. L. Serpa; P. J. C. Sousa; A. N. Coelho-de-Souza; J. H. Leal-Cardoso

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 136 KB
• Volume: 11
• Category: Article
• ISSN: 0951-418X
• DOI: 10.1002/(sici)1099-1573(199712)11:8<552::aid-ptr154>3.0.co;2-n

✦ Synopsis

The effects of the essential oil of Mentha x villosa (EOMV) was investigated in saponin-permeabilized fibres and in intact sartorius muscle of the toad. In intact muscle EOMV at concentrations from 1 to 100 g/mL blocked the contraction induced by high (80 mM) potassium and induced potentiation of caffeine-induced muscle contraction. From 1 to 6 mg/mL EOMV elicited contraction in both depolarized (by 110 mM K + ) and nondepolarized (4 mM K + ) muscle fibres. This contraction was blocked by procaine. At 3 mg/mL EOMV depolarized the normal resting potential from Ϫ 80.77 to Ϫ 71.21 mV, but did not alter the transmembrane potential in the presence of 60 mM K + . EOMV (1 mg/mL) induced contraction of saponin-permeabilized muscle fibres with an intact sarcoplasmic reticulum (SR). These data suggest that EOMV: (i) induces muscle contraction by releasing Ca 2+ from SR; (ii) impairs the excitation-contraction coupling at a step before Ca 2+ release from the SR.