Learn More
The effect of hyper- and hypotonic solutions on the electrical as well as the mechanical activities of the bullfrog ventricle were investigated. Hypertonic solutions up to 400% tonicity, made by adding sucrose, showed two kinds of inhibitory effect; i.e. a consistent, rapid shortening of the action potential duration and a slowly progressing suppression of(More)
INTRODUCTION A study of the effects of hyper -and hypotonic media on resting tension were examined in ventricular muscle of the bullfrog was undertaken because only few studies on resting tension from the viewpoint of E-C coupling in the heart muscle are available. MATERIALS AND METHODS Thin strips obtained from the bullfrog ventricle were perfused in the(More)
The effects of hypotonic solution on the mechanical activities and action potential of the bullfrog atrium were investigated. Exposure of muscle to hypotonic solutions (70% of normal solution) produced initially a transient increase in twitch after which twitch declined below the control level. The response is independent of the kinds of salts withdrawn to(More)
  • H Kawata
  • 1985
Some features of the electrically induced contracture were investigated by means of the partition polarization method in the toe muscles of a bullfrog. Under the current clamp condition and in the presence of tetrodotoxin, a biphasic contracture was induced by strong depolarizing pulses, 1 sec, in duration. The contracture was depressed either by(More)
To elucidate the effect of interleukin-6 (IL-6) on bone and bone marrow (BM), human IL-6 transgenic mice (hIL-6 tgm) were produced. Their bone and BM were examined histologically, radiologically, histomorphometrically, and hematologically on a temporal basis. hIL-6 tgm showed histologically evident neutrophilia in BM. Increase in precursors of granulocytes(More)
Hypertonic solutions were found to exhibit both positive and negative inotropic effects on the contraction of the isolated atrial myocardium of bullfrog. The optimum tonicity for twitch potentiation was about 1.5 T. The mechanism for the positive inotropic action was investigated. The possibility of involvement of an increase in calcium influx during each(More)
1. Single skeletal muscle fibers were transferred from a normal Ringer solution to Na+ ion free solution, and vice versa, and tetanus responses were recorded immediately after the transfer. 2. Fractional tetanus tension recorded immediately after the displacement from the Na+ ion free solution to normal Ringer solution was dependent on fiber diameter. 3.(More)