Details

Autor(en) / Beteiligte

• Wahlqvist, Inger
• Nilsson, Stefan

Titel

The role of sympathetic fibres and circulating catecholamines in controlling the blood pressure and heart rate in the cod, Gadus morhua

Ist Teil von

• Comparative biochemistry and physiology. C, Comparative pharmacology, 1977, Vol.57 (1), p.65-67

Ort / Verlag

England: Elsevier B.V

Erscheinungsjahr

1977

Link zum Volltext

Quelle

Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)

Beschreibungen/Notizen

• 1. The effects of adrenergic blocking agents and pre-treatment with 6-hydroxydopamine and reserpine on pre- and post-branchial blood pressure and heart rate were investigated in the unrestrained, unanaesthetized cod. 2. Yohimbine produced a prominent decrease in both pre- and post-branchial by interfering with an alpha adrenoceptor mediated adrenergic vaso-constrictor “tonus” of the systematic vascular bed. 3. Propranolol inhibited the heart rate, decreased the dorsal aortic pressure and increased the transbranchial drop. The former effect is likely to be caused by blockade of beta adrenoceptors of the heart, the latter effects may be caused by alpha adrenoceptor blocking properties of propranolol affecting the systemic vascular resistance, and/or blockade of beta adrenoceptors of the branchial vascular bed. 4. Neither acute reserpine nor 6-hydroxydopamine affected the blood pressure or heart rate, but chronic (8 days) reserpine treatment produced a significant decrease in post-branchial blood pressure and an increase in the trans-branchial blood pressure drop. 5. It is concluded that the adrenergic “tonus” which affects both heart rate and blood pressure in the cod under the present experimental conditions, is caused mainly by circulating catecholamines rather than activity in adrenergic neurons innervating the heart and vascular bed.