TAURINE AND MYOCARDIAL NORADRENALINE

Taurine (CAS 107-35-17) is an anticonvulsant used also as an adjunct i n the treatment of cardiovascular disorders. Therefore, we studied its effects on nor-adrenergic transmission in the isolated rabbit heart p re-labelled with H-3-noradrenaline. At the concentrations of 1 and 10 mmol/l taurine treatment was without effect on the neuronal and extran euronal uptake of noradrenaline by the myocardial tissue. At the highe st concentration, it decreased the spontaneous release of the transmit ter and enhanced its catabolism. Without any significant effect on tyr amine-induced noradrenaline release, taurine decreased the release of the amine induced by dimethylphenylpiperazinium and nerve stimulation. These results suggested that taurine may reduce the peripheral sympat hetic activity by accelerating noradrenaline catabolism and decreasing its release probably via its ability to prevent a rise of intracellul ar calcium ion.