title: Effect of amphetamine on the transmission of repetitive impulses through the isolated superior cervical ganglion of the rat.
abstract: 1. The cervical sympathetic trunk of the isolated rat superior cervical ganglion was stimulated with short bursts of repetitive pulses. At room temperature with rates of stimulation of 4 Hz and above, the ganglionic action potentials were reduced in size.2. Amphetamine (2.7 x 10(-5)M), which caused some depression of transmission during stimulation at 0.1 Hz, caused a partial reversal of the depression of transmission occurring with rates of stimulation above 4 Hz.3. This action of amphetamine was mimicked by adrenaline (3 x 10(-5)M) and noradrenaline (9.6 x 10(-5)M) but not by isoprenaline (1.8 x 10(-5)M) and was unaffected by propranolol (1.4 x 10(-5)M) but was abolished by prior application of phenoxybenzamine (5.8 x 10(-6)M). Furthermore, this action of amphetamine was unaltered in ganglia taken from rats pretreated with reserpine (single dose of 6 mg/kg, 16 h before dissection).4. Amphetamine had no effect on the surface potentials of the ganglion or on changes in these potentials produced by concentrations of carbachol (5. x 10(-6)M to 5.5 x 10(-3)M).5. It is concluded that amphetamine has a direct action on alpha-adrenoceptors situated at presynaptic sites.
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000661:Amphetamine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000818:Animals; D002217:Carbachol / Q000494:pharmacology; D004558:Electric Stimulation; D004837:Epinephrine / Q000494:pharmacology; D005260:Female; D005725:Ganglia, Autonomic / Q000187:drug effects*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D010643:Phenoxybenzamine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D012110:Reserpine / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects*
chemical_list: D010643:Phenoxybenzamine; D012110:Reserpine; D002217:Carbachol; D011433:Propranolol; D000661:Amphetamine; D007545:Isoproterenol; D009638:Norepinephrine; D004837:Epinephrine