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Central antitussive effect of codeine in the anesthetized rabbit
Michal Simera1, I Poliacek, J Jakus
1Institute of Medical Biophysics, Jessenius Faculty of Medicine, Comenius University, Martin, Slovakia. simera@jfmed.uniba.sk
European Journal of Medical Research
|December 15, 2010
Summary
Codeine effectively suppresses cough centrally in rabbits, with intracerebroventricular administration being 35 times more potent than intravenous. Sneeze and expiration reflexes were unaffected by codeine.
Area of Science:
- Pharmacology
- Neuroscience
- Respiratory Medicine
Background:
- Codeine is a widely used antitussive agent.
- Its central mechanism of action is established, but data in rabbits are scarce.
Purpose of the Study:
- To investigate codeine's effects on cough, sneeze, and expiration reflexes in anesthetized rabbits.
- To compare the efficacy of intravenous and intracerebroventricular administration of codeine.
Main Methods:
- Anesthetized rabbits were administered increasing doses of codeine intravenously and intracerebroventricularly.
- Cough, expiration-like reflex, and sneeze reflex responses to mechanical stimulation were measured.
Main Results:
- Codeine demonstrated a dose-dependent reduction in cough responses via both administration routes.
- Intracerebroventricular administration was approximately 35-fold more potent than intravenous administration for cough suppression.
- Sneeze and expiration reflexes remained unchanged by codeine treatment.
Conclusions:
- The study confirms the central antitussive effect of codeine in a rabbit model.
- Sneeze and expiration reflexes exhibit low sensitivity to codeine.
- The anesthetized rabbit model is validated for studying central antitussive actions.
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