抄録
Effects of hyperosmolality on AV conductivity were studied by the directperfusion of hypertonic glucose or mannitol solution into the AV node artery ofdogs in situ. Animals were bilaterally vagotomized. Infusion of hypertonic solution caused AV block. The minimum osmolality of plasma for inducing the first degree AV block was estimated at roughly 500mOsm/l. When the duration ofinfusion did not exceed one minute, the AV node restored its normal conductivity.Higher osmolality in plasma over 800mOsm/l usually caused a complete block ofthe AV conduction. AV block induced by infusion of a hypertonic solution in ashort time was reproducible in the same animals. An infusion over 10 minutescaused an irreversible AV block. The AV block induced by a hypertonic solutionwas not antagonized by atropine treatment.
