Heteroreceptor-mediated modulation of noradrenaline and acetylcholine release from peripheral nerves

Patterns of fast synaptic cholinergic activation of neurons in the celiac ganglia of cats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1988.255.6.g759 ◽

1988 ◽

Vol 255 (6) ◽

pp. G759-G766

Author(s):

J. P. Niel ◽

N. Clerc ◽

Y. Jule

Keyword(s):

Nerve Stimulation ◽

Peripheral Nerves ◽

Action Potentials ◽

Acetylcholine Release ◽

Single Pulse ◽

Synaptic Activation ◽

Single Neurons ◽

Repetitive Nerve Stimulation ◽

Cholinergic Activation

Fast nicotinic transmission was studied in vitro in neurons of isolated cat celiac ganglia. In the absence of nerve stimulation, neurons could be classified into three types: silent neurons, synaptically activated neurons, and spontaneously discharging neurons. In all three types, fast synaptic activation could be obtained in single neurons by stimulating with a single pulse both the splanchnic nerves or one of the peripheral nerves connected to the ganglia. During repetitive nerve stimulation, a gradual depression of the central and peripheral fast nicotinic activation occurred, which was not affected by phentolamine plus propranolol, domperidone, atropine, or naloxone. Repetitive nerve stimulation was followed by a long lasting discharge of excitatory postsynaptic potentials and action potentials that decreased gradually with time. This discharge, which was probably due to presynaptic or prejunctional facilitation of acetylcholine release from cholinergic terminals, was reduced by the application of phentolamine plus propranolol, domperidone, or atropine and increased with naloxone. The existence of the mechanisms described in this study reflects the complexity of the integrative processes at work in neurons of the cat celiac ganglia that involve fast synaptic cholinergic activation.

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Evidence for a Blood Ganglion Barrier in the Superior Cervical Ganglion of the Rat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053681 ◽

1982 ◽

Vol 40 ◽

pp. 204-204

Author(s):

D. M. DePace

Keyword(s):

Blood Vessels ◽

Superior Cervical Ganglion ◽

Peripheral Nerves ◽

Time Schedule ◽

Transmission Electron ◽

Cervical Ganglion ◽

The Central Nervous System ◽

Cervical Ganglia ◽

Capillary Circulation ◽

And Control

The majority of blood vessels in the superior cervical ganglion possess a continuous endothelium with tight junctions. These same features have been associated with the blood brain barrier of the central nervous system and peripheral nerves. These vessels may perform a barrier function between the capillary circulation and the superior cervical ganglion. The permeability of the blood vessels in the superior cervical ganglion of the rat was tested by intravenous injection of horseradish peroxidase (HRP). Three experimental groups of four animals each were given intravenous HRP (Sigma Type II) in a dosage of.08 to.15 mg/gm body weight in.5 ml of.85% saline. The animals were sacrificed at five, ten or 15 minutes following administration of the tracer. Superior cervical ganglia were quickly removed and fixed by immersion in 2.5% glutaraldehyde in Sorenson's.1M phosphate buffer, pH 7.4. Three control animals received,5ml of saline without HRP. These were sacrificed on the same time schedule. Tissues from experimental and control animals were reacted for peroxidase activity and then processed for routine transmission electron microscopy.

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Intramuscular Nerve and Neuromuscular Junction Alteration In Extraocular Muscles of Diabetic Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120102 ◽

1985 ◽

Vol 43 ◽

pp. 682-683

Author(s):

Bruce R. Pachter

Keyword(s):

Diabetes Mellitus ◽

Peripheral Nerves ◽

Sudden Onset ◽

Extraocular Muscles ◽

Diabetic Patients ◽

Oculomotor Palsy ◽

Third Nerve Palsy ◽

Patients With Diabetes ◽

Intramuscular Nerve ◽

Oculomotor Nerves

Diabetes mellitus is one of the commonest causes of neuropathy. Diabetic neuropathy is a heterogeneous group of neuropathic disorders to which patients with diabetes mellitus are susceptible; more than one kind of neuropathy can frequently occur in the same individual. Abnormalities are also known to occur in nearly every anatomic subdivision of the eye in diabetic patients. Oculomotor palsy appears to be common in diabetes mellitus for their occurrence in isolation to suggest diabetes. Nerves to the external ocular muscles are most commonly affected, particularly the oculomotor or third cranial nerve. The third nerve palsy of diabetes is characteristic, being of sudden onset, accompanied by orbital and retro-orbital pain, often associated with complete involvement of the external ocular muscles innervated by the nerve. While the human and experimental animal literature is replete with studies on the peripheral nerves in diabetes mellitus, there is but a paucity of reported studies dealing with the oculomotor nerves and their associated extraocular muscles (EOMs).

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Innervation of endoneurial microvessels in human sural nerve

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125002 ◽

1992 ◽

Vol 50 (1) ◽

pp. 920-921

Author(s):

John L. Beggs ◽

Peter C. Johnson ◽

Astrid G. Olafsen ◽

C. Jane Watkins

Keyword(s):

Blood Flow ◽

Blood Vessels ◽

Blood Supply ◽

Peripheral Nerves ◽

Sural Nerve ◽

Nerve Fibers ◽

Arterial Supply ◽

Autonomic Nerve ◽

Vasa Nervorum ◽

Endoneurial Blood Flow

The blood supply (vasa nervorum) to peripheral nerves is composed of an interconnected dual circulation. The endoneurium of nerve fascicles is maintained by the intrinsic circulation which is composed of microvessels primarily of capillary caliber. Transperineurial arterioles link the intrinsic circulation with the extrinsic arterial supply located in the epineurium. Blood flow in the vasa nervorum is neurogenically influenced (1,2). Although a recent hypothesis proposes that endoneurial blood flow is controlled by the action of autonomic nerve fibers associated with epineurial arterioles (2), our recent studies (3) show that in addition to epineurial arterioles other segments of the vasa nervorum are also innervated. In this study, we examine blood vessels of the endoneurium for possible innervation.

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Severe Drooling and Treatment With Botulinum Toxin

Perspectives on Swallowing and Swallowing Disorders (Dysphagia) ◽

10.1044/sasd21.1.15 ◽

2012 ◽

Vol 21 (1) ◽

pp. 15-21

Author(s):

Merete Bakke ◽

Allan Bardow ◽

Eigild Møller

Keyword(s):

Botulinum Toxin ◽

Side Effects ◽

Health Risk ◽

Flow Rate ◽

Clinical Evidence ◽

Acetylcholine Release ◽

Psychosocial Problems ◽

Rate Reduction ◽

Local Inhibition ◽

Surgical Treatments

Severe drooling is associated with discomfort and psychosocial problems and may constitute a health risk. A variety of different surgical and non-surgical treatments have been used to diminish drooling, some of them with little or uncertain effect and others more effective but irreversible or with side effects. Based on clinical evidence, injection with botulinum toxin (BTX) into the parotid and submandibular glands is a useful treatment option, because it is local, reversible, and with few side effects, although it has to be repeated. The mechanism of BTX is a local inhibition of acetylcholine release, which diminishes receptor-coupled secretion and results in a flow rate reduction of 25–50% for 2–7 months.

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