Age-associated alterations in calcium current and its modulation in cardiac myocytes

Ying Ying Zhou, Edward Lakatta, Rui Ping Xiao

Research output: Contribution to journalReview article

Abstract

The calcium current is one of the most important components in cardiac excitation-contraction coupling. During aging, the magnitude of L-type Ca++ channel current (I(Ca,L)) is significantly increased in parallel with the enlargement of cardiac myocytes, resulting in unaltered I(Ca,L) density. Since the inactivation of I(Ca,L) is slowed and the action potential duration is prolonged, the net Ca++ influx during each action potential is likely to be increased in senescent hearts relative to young ones. This augmentation of Ca++ influx may be important for the preserved cardiac function of the older heart in the basal state. However, it increases the risk of Ca++ overload and Ca++-dependent arrhythmias in the senescent heart. During stress, the response of I(Ca,L) to β-adrenergic receptor stimulation is markedly reduced, which may be an important cause of the age-related decrease in cardiac reserve function. These age-dependent changes in I(Ca,L) and its modulations are similar to those observed in the enlarged myocytes of the hypertrophied and failing heart.

Original languageEnglish (US)
Pages (from-to)159-171
Number of pages13
JournalDrugs and Aging
Volume13
Issue number2
DOIs
StatePublished - 1998
Externally publishedYes

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ASJC Scopus subject areas

  • Geriatrics and Gerontology
  • Pharmacology (medical)

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