Age-related changes in the transmembrane potential of isolated rabbit sino-atrial nodes and atria

摘要: Transmembrane potentials were recorded from single cells of the sino-atrial (S-A) node and right atrium isolated rabbits different ages (2 to 360 days old). In neonatal rabbit atria. shape pacemaker action same S-A nodal not regular, showing a slow depolarisation during diastole frequently close crista terminalis. The atrial rate decreased, maximal diastolic potential or resting size overshoot increased, durations prolonged with age. Such alterations in membrane related age associated changes rate. maximum rise did significantly differ nodes atria ages. It may be concluded that permeability for K+ is increased and/or Na+ decreased early postnatal period, resulting automaticity parameters potential. relationship between appears altered