| First Author | VanderBrink BA | Year | 2000 |
| Journal | J Cardiovasc Electrophysiol | Volume | 11 |
| Issue | 11 | Pages | 1270-6 |
| PubMed ID | 11083248 | Mgi Jnum | J:113176 |
| Mgi Id | MGI:3664704 | Doi | 10.1046/j.1540-8167.2000.01270.x |
| Citation | VanderBrink BA, et al. (2000) Connexin40-deficient mice exhibit atrioventricular nodal and infra-Hisian conduction abnormalities. J Cardiovasc Electrophysiol 11(11):1270-6 |
| abstractText | INTRODUCTION: Previous electrophysiologic investigations have described AV conduction disturbances in connexin40 (Cx40)-deficient mice. Because expression of Cx40 occurs predominantly in the atria and His-Purkinje system of the mouse heart, the AV conduction disturbances were thought to be secondary to disruption in His-Purkinje function. However, the lack of a His-bundle electrogram recording in the mouse has limited further investigation of the importance of Cx40. Using a novel technique to record His-bundle recordings in Cx40-deficient mice, we define the physiologic importance of deficiencies in Cx40. METHODS AND RESULTS: Ten Cx40-/- mice and 11 Cx40+/+ controls underwent a blinded, in vivo, closed chest electrophysiology study at 9 to 12 weeks of age. In the Cx40-/- mice, the PR interval was significantly longer compared with Cx40+/+ mice (44.6+/-6.4 msec vs 36.0+/-4.1 msec, P = 0.002). Not only the HV interval (14.0+/-3.0 msec vs 10.4+/-1.2 msec, P = 0.003) but also the AH interval (33.2+/-4.8 msec vs 27.1+/-3.7 msec, P = 0.006), AV Wenckebach cycle lengths, and AV nodal effective and functional refractory periods were prolonged in Cx40-/- compared with Cx40+/+ mice. CONCLUSION: Cx40-deficient mice exhibit significant delay not only in infra-Hisian conduction, as would be expected from the expression of Cx40 in the His-Purkinje system but also in the electrophysiologic parameters that reflect AV nodal conduction. Our data suggest a significant role of Cx40 in atrionodal conduction and/or in proximal His-bundle conduction. |
