- Title
- Cardioselective inhibition of sympathetic control by atenolol in man does not evoke fatigue: a double-blind study
- Creator
- Quail, A.; White, Saxon William; Horton, K.; Buxton, J.; van der Touw, T.; Cottee, D.
- Relation
- Acta physiologica Scandinavica. Supplementum Vol. 136, Issue 584
- Publisher
- Wiley-Blackwell Publishing
- Resource Type
- journal article
- Date
- 1989
- Description
- Cardioselective sympathetic blockade is useful in clinical management but the side-effect of fatigue (enhanced tiredness during exercise) suggests that physiological compensations are inadequate. Pilot studies confirmed that the effects of exercise on cardiac output (CO; impedance cardiography), serum lactate (SL) and rating of perceived exertion (RPE) were reproducible within subjects and between weeks over 4 weekly tests. In 6 untrained normotensive men (age 41.1±2.13yr) the effects of 2 doses 24hr apart of either atenolol 50 mg (A), atenolol 50mg plus chlorthalidone 12.5mg (AC), placebo 1 or placebo 2, were studied at rest and during incremental exercise to maximum on 4 occasions in each subject 1 week apart using a double blind, randomized protocol. The use of A was marked by lassitude (a feeling of tiredness at rest). On average both A and A+C each lowered resting and exercise heart rate, arterial pressure and CO to a similar degree. Nevertheless, the external work performed and the exercise related rise in RPE and SL was similar irrespective of the drug used as was the level to which total peripheral resistance fell. Thus selective cardiac sympatholysis does not result in fatigue or its potential metabolic causes at rest or over the full range of effort. Lassitude is possibly due to minimal penetration of the blood brain barrier by atenolol.
- Subject
- atenolol; exercise; fatigue; heart rate
- Identifier
- http://hdl.handle.net/1959.13/939201
- Identifier
- uon:12753
- Identifier
- ISSN:0302-2994
- Language
- eng
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