title: Ganglionic neuronal mechanisms involved in circulatory control system.
abstract: Intracellular tonic activity and responses to orthodromic stimuli were recorded from the neurones of rabbit superior cervical ganglion and compared with those recorded from the nerves containing pre- and postganglionic nerve fibres, with the use of a coherent recording technique. It was found that: (1) firing of each ganglion neurone is triggered by two presynaptic inputs, single and multiple, formed by a single preganglionic nerve fibre whose discharges evoke the postsynaptic spikes correlated with cardiac rhythm, and by a few converging preganglionic nerve fibres which evoke the postsynaptic spikes, either correlated with cardiac rhythm or irregular, only if two or more of them discharge together, correspondingly; (2) about 240 neurones of the ganglion, on the average, fire synchronously during their tonic activity, being driven by only three preganglionic nerve fibres; (3) only about 9% of a "neural unit", the number of the ganglion neurones receiving innervation from the same preganglionic nerve fibre, are discharged during their tonic activity through a single input, while the rest of neurones are either discharged through a multiple input (17%), or generate only the excitatory postsynaptic potentials subthreshold for spike generation (73%). The results obtained suggest that the ganglionic neuronal mechanisms responsible for vasomotor control involve much more complex ganglionic integrative processes than it has been commonly thought.
authors.affiliation: Department of Autonomic Nervous System Physiology, Bogomoletz Institute of Physiology, Kiev, Ukraine.
authors.forename: V
authors.initials: V
authors.lastname: Skok
authors.forename: A
authors.initials: A
authors.lastname: Ivanov
authors.forename: L
authors.initials: L
authors.lastname: Tatarchenko
authors.forename: V
authors.initials: V
authors.lastname: Maslov
mesh_terms: D000818:Animals; D002320:Cardiovascular Physiological Phenomena; D004594:Electrophysiology; D066298:In Vitro Techniques; D009131:Muscle, Smooth, Vascular / Q000294:innervation / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D011817:Rabbits; D017661:Receptors, Presynaptic / Q000502:physiology; D017783:Superior Cervical Ganglion / Q000166:cytology / Q000502:physiology*
chemical_list: D017661:Receptors, Presynaptic