Abstract：
:The ability of the heart to respond to adrenergic stimulation diminishes with aging, and this may be one of the factors contributing to the age-associated decline in cardiac stress responsiveness. On the other hand, little is known about the impact of aging on the responsiveness of the heart to cholinergic stimulation. In this study, we determined the chronotropic and inotropic responses of the isolated, Langendorff-perfused hearts from adult (6-8 months) and aged (28-30 months) rats to cholinergic agonists so as to assess age-related alterations in postsynaptic cholinergic control of heart function. The results showed the following. (i) In isolated perfused spontaneously bearing rat hearts, the negative chronotropic response to acetylcholine (10(-9)-10(-5) M) was up to 4-fold greater in the aged compared with adult hearts; this age-related difference was less marked (2-fold) but not abolished in the presence of a maximally effective concentration (5 microM) of the cholinesterase inhibitor eserine. (ii) The cholinesterase-resistant agonist carbachol (10(-9)-2.5 x 10(-6) M) elicited a 2- to 3-fold greater negative chronotropic response in the aged compared with adult hearts. (iii) In isolated perfused, electrically paced (4 Hz) rat hearts, carbachol (10(-9)-10(-5) M) elicited a concentration-dependent negative inotropic response, which was 2-fold greater in the aged compared with adult heart at all carbachol concentrations. (iv) Acetylcholinesterase activities (micromoles per gram per hour) were 50-60% lower in the aged atria (83 +/- 21) and ventricles (24 +/- 6) than in adult atria (210 +/- 20) and ventricles (47 +/- 7).(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Su N,Narayanan Ndoi
10.1139/y92-232subject
Has Abstractpub_date
1992-12-01 00:00:00pages
1618-24issue
12eissn
0008-4212issn
1205-7541journal_volume
70pub_type
杂志文章abstract：:The threshold for electrically induced ventricular fibrillation was determined in anesthetized open-chest dogs, before and after blockade of atrioventricular (A-V) conduction. Without exception, the threshold was significantly elevated after creation of the block. The precise mechanism of this effect is not known at t...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y83-160
更新日期：1983-09-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y94-002
更新日期：1994-01-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y94-096
更新日期：1994-06-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
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更新日期：1997-04-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
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更新日期：1996-01-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
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更新日期：2005-01-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
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更新日期：1997-10-01 00:00:00
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doi：10.1139/y11-080
更新日期：2011-11-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y81-081
更新日期：1981-06-01 00:00:00
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pub_type： 杂志文章,评审
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更新日期：2009-04-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y86-117
更新日期：1986-06-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y86-209
更新日期：1986-09-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y2012-076
更新日期：2012-06-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y91-203
更新日期：1991-09-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2017-0003
更新日期：2018-02-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：1998-01-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y90-039
更新日期：1990-02-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y77-177
更新日期：1977-12-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
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pub_type： 杂志文章
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更新日期：1990-03-01 00:00:00
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更新日期：1986-10-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
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更新日期：1984-08-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
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更新日期：1994-09-01 00:00:00
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doi：10.1139/y09-001
更新日期：2009-03-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
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更新日期：1994-10-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：2001-09-01 00:00:00
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更新日期：2003-08-01 00:00:00
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pub_type： 杂志文章
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更新日期：2016-04-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y77-066
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