DISADVANTAGES OF COCAINE AS A NEURONAL UPTAKE BLOCKING AGENT: COMPARISON WITH DESIPRAMINE IN GUINEA‐PIG RIGHT ATRIUM

Abstract

Cocaine and desipramine (DMI) are widely used as neuronal uptake blocking agents in studies of cardiac sympathetic transmission in isolated tissue preparations. It is generally assumed that these pharmacological tools do not alter transmitter release or postjunctional effector response. To test this assumption, we have compared the effects of cocaine and DMI on rate responses to sympathetic nerve stimulation and exogenous noradrenaline in guinea‐pig isolated right atria. Right atria were equilibrated with the irreversible α‐adrenoreceptor antagonist benextramine to prevent any effect of presynaptic α‐adrenoreceptors. Cumulative (–) noradrenaline concentration‐response curves were shifted to ..