S-Space College of Medicine/School of Medicine (의과대학/대학원) Dept. of Medicine (의학과) The Seoul Journal of Medicine The Seoul Journal of Medicine Vol. 21 No.1 (1980)
Diphenylhydantoin(DPH)이 심실근의 수축 및 활동전압에 미치는 영향
Effect of Diphenylhydantoin(DPH) on Elcctrophysiological property of rabbit papillary muscle
- Issue Date
- 서울대학교 의과대학
- Seoul J Med, Vol.21 No.1, pp. 14-20
- The effects of diFhenylhyc€ntoin(DPH) en the : mechanical and electrical responses of rabbit papillary
muscles were studied with conventional micro'
1. The resting membrane potential of the rabbit
papillary muscle was -85~-80mV, the duration of
action potnetial 150~200msec, and Vmax 600v/s in
normal Tyrode solution.
2. DPH did not change resting membrane potential
and amplitude of action potential, but the duration
of 50% repolarization was decreased to 93. 5±2. 5,
93. 8±1. 6 and 87. 5±1. 2% of normal in 3, 10, 30mg/l
-of DPH respectively. Vmax, after adding DPH, was
increased to 130±2.4, 130±3.2 and 121. 6±2. 8%
·of normal in 3,10, 30mg/l, and it was more prominent
in lower concentrations of DPH.
3. In partially depolarized muscle by 18mM-K, the
.amplitude of action potential was decreased to 90.5
±1. 3, 89. 0±2. 5 and 83. 3±1. 7%, and the duration
of action potential was similarly decreased to 89. 2±
.2.1, 78. 5±1. 8 and 75. 0±1. 0% of the control at the
concentration of 3,10, 30mg/l of DPH, respectively.
4. Contractility was decreased in both normal and
K·Tyrode solution by DPH and it was dose-dependent,
The above results suggested that the shortening of
action potential duration and negative inotropic effect
of DPH were mainly due to decreased slow inward
current, especially calcium current.