Open AccessThe Rho/Rho‐kinase Systems Are Involved in Rapid Pacing‐induced Changes of Atrial Refractory Period in a Canine Model
Author(s) -
Furusho Hiroshi,
Sakagami Satoru,
Takamura Masayuki,
Kitano Katsunori,
Abe Tsuyoshi,
Hirazawa Motoaki,
Usui Soichiro,
Okajima Masaki,
Saeki Takahiro,
Maruyama Michiro,
Kaneko Shuichi,
Takata Sigeo
Publication year - 2006
Publication title -
journal of arrhythmia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.463
H-Index - 21
eISSN - 1883-2148
pISSN - 1880-4276
DOI - 10.1016/s1880-4276(06)80015-3
Subject(s) - medicine , verapamil , fasudil , effective refractory period , refractory period , atrium (architecture) , cardiology , electrophysiology , rho kinase inhibitor , rho associated protein kinase , anesthesia , kinase , atrial fibrillation , chemistry , calcium , biochemistry
The Rho/Rho‐kinase pathway has been related to various physiological responses of the cardiovascular system. Previous reports have suggested a significant effect of Rho signals on the electrophysiological characteristics of the heart. We hypothesized that the Rho/Rho‐kinase system would contribute to the rapid pacing‐related change of atrial effective refractory period (AERP). Methods and Results: In 17 dogs, AERP was measured at the right atrial appendage (RAA) and posterior left atrium (LA) before, during, and after 6‐hours rapid atrial pacing at 500 bpm. Saline control (n = 5), verapamil (n = 5), or fasudil (n = 7) were infused throughout the protocol. The shortening of AERP after rapid pacing was abrogated by the administration of verapamil, as reported in previous studies. Furthermore, fasudil (Rho/Rho‐kinase inhibitor) influenced the change of AERP in a manner similar to the infusion of verapamil throughout the experiments. Conclusions: Since the AERP was attenuated by fasudil, rapid pacing‐related atrial electrophysiological changes might involve the Rho/Rho‐kinase pathway.