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At least 19 recordsLinked to original sources
PubMed1979

Substance P-, VIP-, and enkephalin-like immunoreactivity in the human vagus nerve.

The human vagus nerve has been investigated for the presence of substance P (SP), vasoactive intestinal polypeptide (VIP), and enkephalin (ENK) using immunohistochemistry. After 0.5-4 hr of nerve ligation during surgical operations two right thoracic main truncs, two anterior subdiaphragmal trunks, and four anterior nerves of Latarjet were found to contain accumulation of immunoreactive material in nerve fibers above the ligation. Very high numbers of SP-, medium numbers of ENK-, and low number of VIP-immunoreactive fibers were seen. The relative proportions were similar at all levels studied. These data thus indicate the presence and axonal transport of SP-, ENK-, and VIP-like peptides in the human vagus nerve. Our observations in humans correlate well with results obtained from other species. Thus gastrointestinal vagal sensory mechanisms may be mediated by SP (and possibly VIP) and some motor mechanisms by ENK.

Endorphins↗
PubMedDate not supplied

Regulation of motor activity of omasum after blockade of vagus nerves.

In 3 sheep with subcutaneously exposed vagus nerves and with chronic large fistula of the rumen pharmacological analysis of the motor activity of omasum was carried out after blockade of vagus nerves. The contractions of omasal canal, reticulum and rumen were recorded by the baloon method. After blockade of the vagus nerves with anesthetics the proper pharmacological agents were administered in intravenous injections. In the light of the obtained results it was found that contractions of the omsal canal, persisting after vagal blockade, are independent of the influence of the autonomic system and they are probably due to myogenic automatism. It has been also demonstrated that both alpha and beta adrenergic receptors participate in regulation of the tonous of omasum musclular layers.

Animals↗
PubMed1978

Motor innervation of striated oesophageal muscle. Part 2. Characteristics of the oesophagomotor fibres in the rat studied by implanting the vagus nerve into a skeletal muscle.

In 12 rats the right vagus nerve distal to its recurrent laryngeal branch was implanted into the inferior segment of the denervated sternohyoid muscle. One month after implantation the first signs of neuromuscular transmission at the vagal motor endings could be recorded. Two months after implantation the reinnervated muscles showed vigorous contractions on electrical stimulation of the vagus nerve. During the performance of propulsive waves of the oesophagus the implanted vagus nerve caused clonic to tetanic contractions of the sternohyoid muscle, thus proving the oesophagomotor genesis of the reinnervating nerve fibres. In addition, the vagus-innervated motor end-plates were shown to exhibit the same ultrastructural peculiarities as the original neuromuscular junctions of the oesophagus. In sections stained for cholinesterase it could be demonstrated that the oesophagomotor fibres had preferentially reinnervated the denervated motor end-plates. In many instances the subneural apparatus was not completely covered by the vagal axon terminals. Newly formed, ectopic vagal motor endings were few in number and confined to muscle fibres immediately adjacent to the site of nerve-implantation. Six months after implantation some of the vagal motor endings showed signs of degeneration. As in the oesophagus, the reinnervating oesophagomotor fibres proved to be unmyelinated, sometimes forming a plexus-like intramuscular network before terminating at motor end-plates. Myelinated vagal nerve fibres were also observed running between the skeletal muscle fibres, but they did not establish any demonstrable form of neuromuscular contacts. It was concluded that, in the rat, the myelinated fibres of the oesophageal nerves are afferent, whereas the oesophagomotor fibres, although supplying striated muscle, are unmyelinated.

Animals↗
PubMed1976

Effect of vagus nerve stimulation upon excitability of the canine ventricle. Role of sympathetic-parasympathetic interactions.

The effect of vagus nerve stimulation on ventricular excitability was studied in 28 dogs under various conditions of adrenergic neural tone. Strength-interval curves were delineated from the apex of the right ventricular endocardium with a transvenous bipolar catheter. Vagus nerve stimulation in both closed chest and open chest dogs shifted the strength-interval curve 6 to 8 msec later into electrical diastole (P less than 0.001). Left stellate ganglion stimulation shifted the strength-interval curve 9 to 11 msec earlier into diastole (P less than 0.001). The effect of simultaneous left stellate ganglion and vagus nerve stimulation was not significantly different from that of left stellate ganglion stimulation alone. The influence of vagus nerve stimulation on the strength-interval curve under basal conditions was abolished by acute beta adrenergic blockade with propranolol. It is concluded that vagus nerve stimulation affects ventricular excitability as well as vulnerability by opposing the effects of sympathetic neural tone.

Adrenergic beta-Antagonists↗
PubMedDate not supplied

Effects of cervical vagus nerve stimulation on hypothalamic neuronal activity.

The effects of cervical vagus nerve stimulation on the activity of 56 neurons recorded in various parts of the rat brain were determined. Recordings were made from neurons in both the ipsilateral and contralateral hemispheres during vagus nerve stimulation. Both frequency, 10 to 100 Hz, and voltage, 1 to 20 V, of 0.5 msec pulses were applied to the nerve in a random manner over a 4 sec period while monitoring ongoing single neuronal activity. Frequency response relationships were established for 64% of the lateral preoptic-lateral hypothalamic-medial forebrain bundle (LPA-LH-MFB) neurons which were tested. Four types of LPA-LH-MFB neuronal responses were observed. Twenty percent of the neurons increased in discharge frequency as stimulation frequency was increased, 9% increased in discharge frequency as stimulation frequency was decreased, 23% decreased in discharge frequency as stimulation frequency was increased, and 14% decreased in discharge frequency as stimulation frequency was decreased. Increasing the stimulation voltage always enhanced the magnitude of the effects observed due to changing the stimulation frequency. Neurons observed in some other parts of the brain were not affected by the same stimulation. In addition, cells tested in the LPA-LH-MFB area which were previously tested and affected by gastric distension were also affected similarly by vagus nerve stimulation. Results are discussed in terms of peripheral afferent control over LPA-LH-MFB neuronal activity related to ingestive behavior.

Afferent Pathways↗
PubMed1979

Substance P in the vagus nerve. Immunochemical and immunohistochemical evidence for axoplasmic transport.

1. The presence of immunoreactive substance P (I-SP) in the vagus nerve of 5 species was demonstrated by radioimmunoassay. Different amounts of SP per unit weight were found: Guinea pig greater than cat greater than rabbit, rat and cattle. 2. Infranodose ligations of the vagus nerve of cats and rabbits caused an accumulation of I-SP proximal but not distal to the ligation. The results obtained by radioimmunoassay and immunohistochemistry indicate a somatofugal axoplasmic transport of SP. 3. Double ligation experiments revealed that about 37% of I-SP of the cat vagus nerve are mobile. The transport rate of this mobile I-SP was found to be 170 mm per day. 4. Locally applied colchicine resulted in a similar accumulation of I-SP as after ligations. This is evidence favouring the involvement of microtubuli in the axoplasmic transport of SP. 5. Immunohistochemical data show that SP-fibers account for about 10% of the axons in the cat vagus nerve. Most of these SP-fibers seem to be unmyelinated. 6. Supranodose extracranial ligations of the cat vagus nerve led to an accumulation of I-SP on both sides of the ligature. Part of the SP-fibers are, therefore, afferent and their cell bodies are located in the nodose ganglion. The presence of efferent SP-fibers cannot be excluded.

Animals↗
PubMedDate not supplied

Effects of strychnine and picrotoxin on the activity of laryngeal and phrenic motoneurons during stimulation of vagus nerve.

Effects of strychnine and picrotoxin on the activity of laryngeal and phrenic motoneurons during stimulation of vagus nerve. Acta Physiol. Pol., 1977, 28 (1): 1-11. In paralyzed cats the activity of "single fibres" in the recurrent laryngeal nerve and phrenic nerve was recorded. The afferent part of the vagus nerve was stimulated electrically at a frequency of 200 Hz, the duration of one impulse was 1 msec and voltage values used were 0.1, 0.2 and 0.3 V. Stimulation was carried out in paralyzed animals and then after intravenous administration of strychnine 0.3 mg/kg and picrotoxin 1.0 mg/kg. Administration of the drugs was sufficient to induce in both nerves appearance of additional impulses of varying amplitude. Stimulation after administration of strychnine and picrotoxin caused partial inhibition of the activity of both nerves (less significant than before administration of drugs). The authors believe that the mechanisms of presynaptic and postsynaptic inhibition participate in the activity of nervous pathways conveying the inhibitory effect of the vagus nerve to the laryngeal and phrenic motor neurons.

Action Potentials↗
PubMed1977

The dorsal motor nucleus of the vagus nerve of the cat: localization of preganglionic neurons by quantitative histological methods.

The dorsal motor nucleus of the vagus nerve (DMX) of adult cats and young kittens was studied by quantitative light microscopic methods. In normal animals, the DMX was found to contain no distinct subgroupings of neurons, based on somatic volume or Nissl pattern. Retrograde perikaryal responses to axotomy of neurons in the DMX were found to be of a more subtle nature than those seen in other types of neurons. Quantitative methodology applied to the axotomy than could be obtained by routine microscopic observations. Changes which occurred included a slight chromatolytic reaction, and a decrease in the volume of the nucleus followed by an increase in somatic volume. These morphological alterations were affected by the factors of age of the animal, time after axotomy, and length of the intact proximal axon stump. More pronounced perikaryal changes occurred when the vagus nerve was recut at a more proximal level five days after the first vagotomy. Interpretation of the data yielded the conclusion that most if not all neurons of the ipsilateral DMX contribute axons to the cervical vagus nerve. In addition, at least 10% of the neurons on the side contralateral to vagotomy showed signs of retrograde reaction. It was therefore concluded that there exists in the vagus nerve a population of axons with cell bodies located in the contralateral DMX.

Animals↗
PubMed1978

Motor innervation of the striated oesophagus muscle. Part 1. Intramural distribution of the right and left vagus nerve in the rat oesophagus as revealed by the glycogen depletion technique.

The muscularis propria of the rat oesophagus is entirely made up of striated muscle fibres. All fibres are of the same histochemical type, which is characterized by high activity of actomyosin ATPase, medium activity of oxidative enzymes and relatively strong reaction for phosphorylase. Prolonged stimulation (10 Hz, 30 min) of the vagus nerves causes depletion of the glycogen content of the oesophageal muscle fibres. This stimulation effect can be visualized by means of the PAS technique as well as by the histochemical reaction for phosphorylase. In 8 animals the right and in 8 animals the left vagus nerve were stimulated repetitively and the stimulated muscle fibres were identified in transverse sections of the oesophagi, stained for phosphorylase. The muscle fibres supplied by one vagus nerve are distributed all over the circumference of the oesophagus. In the upper third of the oesophagus stimulation of either vagus nerve depletes slightly less than 50% of the muscle fibres, whereas in the lower two-thirds the right vagus nerve seems to predominate to a certain degree. In 3 animals both vagus nerves were stimulated simultaneously. Bilateral stimulation produced a very extensive depletion. Only a few muscle fibres remained unaffected. Functional implications of the results, the question of polyneuronal innervation and the role of the myenteric plexus are discussed.

Animals↗
PubMed1979

[Topography of the vagus nerves in the oesophageal hiatus (author's transl)].

Topographic variations of the vagus nerves are important to know for modern surgery of the stomach (SPV). That is why vagus nerves were prepared in 53 human cadavers. Based on these findings the perioesophageal plexus and the vagal truncs in the hiatus oesophageus are precisely described including the situs of a diaphragmatic hernia and an intrathoracic aortic aneurysm.

Aortic Aneurysm↗
PubMed1978

Effects of pressure on fast axoplasmic flow. An in vitro study in the vagus nerve of rabbits.

By using a radially directed stream of fluid it is possible to compress a section of a nerve in vitro by known pressures without interrupting the supply of oxygen and nutrients to the nerve. Motor neurons of the vagus nerves of rabbits labelled with 3H-leucine were used at room temperature. When a nerve was subjected to 20 mmHg pressure fast axoplasmic flow was not altered, but at 30 mmHg there was a slight but consistent inhibition, which was even more marked at 60 mmHg and still more at 90 mmHg. The pressure induced block of axoplasmic flow was reversible when 60 mmHg pressure was applied for as long as 4 h, when the nerves were compressed for 15 h there was reversibility in only 5 out of 8 cases.

Animals↗
PubMed1978

Specific binding of staphylococcal alpha-toxin to isolated rabbit vagus nerves in vitro.

The binding of staphylococcal [125I]alpha-toxin to rabbit vagus nerves in vitro was a saturable process. The radiolabeled alpha-toxin binding was reduced by the coaddition of added navive alpha-toxin, indicating that the binding is specific. Sucrose gradient analysis of detergent-extracted complexes of [125I]alpha-toxin-rabbit vagus nerves showed both high and low S-value peaks analogous to those observed with similarly treated alpha-toxin-rabbit erythrocyte preparations (P. Cassidy and S. Harshman, Biochemistry, in press).

Animals↗
PubMed1979

Neurilemmoma of the vagus nerve: a case report.

A CASE of an unusually big neurilemmoma arising from the vagus nerve in the neck is presented in this paper. The tumour was so big that it could not be removed until its size had been reduced by the removal of about 15 cc of its fluid contents. The patient had a cardiac arrest on removal of the tumour, denoting probable stimulation of the vagus nerve leading to vagal arrest. His heart started, however, after resuscitative measures and he has not shown any residual cardiac abnormalities, thus indicating that the main vagal trunk was undamaged.

Cranial Nerve Neoplasms↗
PubMed1977

[Glossopharyngeal neuralgia associated with the right-bundle branch block and hypotension on sectioning a rootlet of the vagus nerve--case report (author's transl)].

A 74-year-old female who complained of severe attacks of pain in the throat and neck on the left side was first admitted to our hospital in 1971. Carbamazepine was effective at this time, and so she could be discharged. She was readmitted to the hospital in 1974 because of severe stabbing paroxysms of pain in the left throat, radiating into the auricular region as frequent as more than ten times a day. Paroxysms could not be alleviated by large doses of Carbamazepine, and side effects of the drug ensued. The pain could be easily elicited by talking, laughing, swallowing, pulling the left ear and pushing the left tragus. Block of the left 9th nerve with xylocaine produced complete relief of pain for 30 minutes to 1 hour; Plain skull X-rays and veretebral angiograms were normal. The patient was operated under general anesthesia in the sitting position. With the left suboccipital craniectomy, the left 9th nerve was cut without any change on ECG. Pulse rate, and blood pressure. Upon touching vagus nerve, the ventricular extrasystole and hypotension occurred. After the blood pressure restored to normal level and the extrasystole disappeared with administration of atropine and carnigen, the uppermost rootlet of the vagus nerve was cut. The blood pressure dropped abruptly again followed by the right bundle-branch block on ECG for approximately 20 minutes. Postoperatively, she was lethargic and had disorientation, delusion and disorientation. We attributed these symptoms to the hypoxia in operative procedure. The symptoms completely disappeared on the fifth postoperative day. The patient has been perfectly free from pain at the 15 month's follow-up without neurological or mental deficit except diminished gag reflex on the left side. We reported this our experienced case and discussed about the mechanism of the hypotension on sectioning a rootlet of the vagus nerve with literatures.

Aged↗
PubMed1977

[Nineteen years experience with surgical correction of disorders of swallowing and voice following vagus nerve paralysis (author's transl)].

An operation for the correction of swallowing and voice following paralysis of the vagus nerve is described. The operation is divided into four parts which are performed either in one or two stages. These include: 1. extramucosal myotomy of the pars fundiformis of the cricopharyngeus muscle; 2. correction of vocal cord paralysis by the rotation of the arytenoid cartilage and cartilage implant into the paralyzed vocal cord; 3. resection of the paralyzed wall of the pharynx; 4. fixation of the paralyzed soft palate to the posterior wall of the pharynx. Nineteen years experience with the four different parts of the operation are discussed.

Deglutition Disorders↗