Search results for "Rat heart"
showing 3 items of 3 documents
Nicotine receptors do not modulate the 3H-noradrenaline release from the isolated rat heart evoked by sympathetic nerve stimulation.
1982
Isolated rat hearts with the right sympathetic nerves attached were perfused at a constant flow rate of 7 ml/min with Tyrode's solution. (-)-3H-Noradrenaline (final concentration 10–13.9 nM) was infused for 10 min to label the noradrenaline stores. After wash-out the sympathetic nerves were stimulated electrically (3 Hz, 180 impulses, 1 ms, 20–30 mA) three times (S1–S3) at intervals of 15 min. 3H-Noradrenaline and its metabolites were determined by liquid scintillation counting according to Graefe et al. (1973). Both, nicotine 50 μM and p-aminophenethyltrimethylammonium (PAPETA) 30 μM, enhanced the 3H-noradrenaline overflow in the absence of nerve stimulation. The effect of PAPETA was bipha…
Die Beziehung zwischen der Guanethidin-Konzentration im Rattenherzen und dem Noradrenalingehalt
1962
Guanethidine was intravenously injected into rats and was subsequently determined in the hearts by extracting the tissue with trichloroacetic acid, purifying the extracts on cation exchange columns and by paper chromatography, and coupling the guanethidine with ninhydrin in alkaline solution before fluorimetric estimation. The concentration in the heart reached a maximum of 9 μg/g within 15 min of injecting 15 mg/kg, and was still 6.2 and 5.7 μg/g after 1 and 3 hours, respectively. Guanethidine caused a decrease of the heart noradrenaline concentration, measured fluorimetrically, by 56% in 3 hours and by 93% in 14 hours. The adrenaline concentration was likewise decreased. A metabolite with…
Die Wirkung von Harmalin auf die Konzentration von Noradrenalin und Adrenalin im Herzen
1959
A single injection of harmaline increases the noradrenaline and adrenaline concentration in the rat heart. The maximum effect is obtained after about 40 min.