ISSN:
1432-1912
Keywords:
Arterial Blood Pressure
;
Action Potentials
;
Central Sympathetic Activity
;
Central Respiratory Activity
;
α-Methyl-dopa
;
Arterieller Blutdruck
;
Aktionspotentiale Zentrale SympathicusaktivitÄt
;
Atemzentrum
;
α-Methyl-dopa
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary The centralnervous sympathetic inhibitory and hypotensive effects ofα-methyl-dopa were studied in anaesthetized rats and cats. Preganglionic action potentials of the cervical sympathetic nerve were recorded simultaneously with the arterial blood pressure and evaluated quantitatively. Student'st-test was applied for statistical analysis. The experiments show thatα-methyl-dopa produces no significant hypotensive or sympathetic inhibitory effects at a dosage of 400 mg/kg i. v. during a 2 hr period after administration. Only after pretreatment for 4 consecutive days with a total dosage of 400–2000 mg/kg i.p. was there an inhibition of the spontaneous sympathetic activity as well as of that induced by nikethamide or asphyxia. Therefore the blockade affected not only the reflex but also the primarily central nervous patterns of discharges in the sympathetic nerve. Although a depression of sympathetic activity was already observed with doses which failed to produce a significant fall in blood pressure, our results suggest that a central nervous mechanism of action participates in the hypotensive effect ofα-methyl-dopa.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00997171
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