Inotropic responses to field stimulation in isolated atrial and ventricular muscle
| Autor: | J J Mitchell, Maurice F. Murnaghan |
|---|---|
| Rok vydání: | 1980 |
| Předmět: |
Inotrope
medicine.medical_specialty Cardiotonic Agents Guinea Pigs Adrenergic chemistry.chemical_compound Procaine Internal medicine medicine Animals Pindolol business.industry Sotalol General Medicine Myocardial Contraction Electric Stimulation Rats Atropine Endocrinology chemistry Tetrodotoxin Cholinergic Rabbits business Autonomic Nerve Block medicine.drug |
| Zdroj: | Irish Journal of Medical Science. 149:228-235 |
| ISSN: | 1863-4362 0021-1265 |
| Popis: | 1. Field stimulation of autonomic nerve fibres in rat, guinea-pig and rabbit atria caused an initial negative followed by a positive inotropic response which were blocked by tetrodotoxin. 2. Atropine blocked the negative and potentiated the positive inotropism. Procaine had a similar anti-muscarinic effect but lignocaine, cinchocaine and amethocaine had not. Cocaine potentiated the positive inotropic effect apparently by inhibiting the reuptake of noradrenaline into the adrenergic nerve fibres. Hemicholinium exhibited an antimuscarinic effect on these preparations. Sotalol, pindolol and debrisoquine antagonized the positive inotropic effect. 3. There was some indication of variation in the atrial preparations among the different animal species to the drugs tested. 4. Ventricular preparations invariably did not exhibit a negative inotropic response but a positive response could be unmasked, or if present potentiated, by atropine. 5. Potentiation of the positive inotropic responses by anticholinergic drugs could have been due to blockade of cholinergic presynatptic receptors on adrenergic nerves. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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