Is it autonomic hyperreflexia or denervation supersensitivity?
Explore the source record for details and available documents.
Autonomic Nervous System Diseases↗
SEARCH · PubMed Health
Results for “Autonomic Denervation”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Regulation of salivary gland function by autonomic nerves.
Oral homeostasis is dependent upon saliva and its content of proteins. Reflex salivary flow occurs at a low 'resting' rate and for short periods of the day more intense taste or chewing stimuli evoke up to ten fold increases in salivation. The secretion of salivary fluid and proteins is controlled by autonomic nerves. All salivary glands are supplied by cholinergic parasympathetic nerves which release acetylcholine that binds to M3 and (to a lesser extent) M1 muscarinic receptors, evoking the secretion of saliva by acinar cells in the endpieces of the salivary gland ductal tree. Most salivary glands also receive a variable innervation from sympathetic nerves which released noradrenaline from which tends to evoke greater release of stored proteins, mostly from acinar cells but also ductal cells. There is some 'cross-talk' between the calcium and cyclic AMP intracellular pathways coupling autonomic stimulation to secretion and salivary protein secretion is augmented during combined stimulation. Other non-adrenergic, non-cholinergic neuropeptides released from autonomic nerves evoke salivary gland secretion and parasympathetically derived vasointestinal peptide, acting through endothelial cell derived nitric oxide, plays a role in the reflex vasodilatation that accompanies secretion. Neuronal type, calcium-activated, soluble nitric oxide within salivary cells appears to play a role in mediating salivary protein secretion in response to autonomimetics. Fluid secretion by salivary glands involves aquaporin 5 and the extent to which the expression of aquaporin 5 on apical acinar cell membranes is upregulated by cholinomimetics remains uncertain. Extended periods of autonomic denervation, liquid diet feeding (reduced reflex stimulation) or duct ligation cause salivary gland atrophy. The latter two are reversible, demonstrating that glands can regenerate provided that the autonomic innervation remains intact. The mechanisms by which nerves integrate with salivary cells during regeneration or during salivary gland development remain to be elucidated.
Animals↗
Selective denervation of the heart.
Total denervation of the canine heart consisted of intrapericardial neural dissection of the left atrium, left superior pulmonary vein, and main pulmonary artery and cutting of the ventrolateral cardiac nerve (stage I). The fat pad and all nerves were removed from between the pulmonary artery and aorta (stage II). Dissection proceeded from the pericardial reflection along the superior vena cava to the azygos vein, which was cleared, double tied, and cut. The right pulmonary artery was cleaned, and the superior right atrium was dissected to its intersection with the left atrium (stage III). Denervation was tested by electrical stimulation of both vagi and stellate ganglia, while recording inotropic, chronotropic, and dromotropic events, before and after each stage. Stage I deleted most left autonomic input to the heart without interrupting right sympathetics. Stage II completed left autonomic denervation but preserved much of the right sympathetic input. Large nerves along the dorsal surface of the pulmonary artery carried inputs from both left and right sympathetics. Stage III completed the denervation of atrioventricular and sinoatrial nodal structures and removed all remaining ventricular inotropic influences. Selective denervation of atrioventricular and sinoatrial nodal regions appears feasible for preparation of chronic canine models.
Animals↗
Increased defibrillation threshold due to ventricular fibrillation duration. Potential mechanisms.
The duration of ventricular fibrillation (VF) that precedes a high energy shock has been recognized as a critical determinant of defibrillation outcome. Factors such as metabolic acidosis or alkalosis do not affect outcome. The authors hypothesized that release of myocardial adenosine during VF could potentially mediate the time-dependent effects of VF duration on defibrillation. Defibrillation threshold (DFT) was therefore determined in dogs during concurrent infusion of adenosine and dipyridamole (a nucleoside transport blocker). Transthoracic DFT increased by approximately 50%, whereas transmyocardial DFT increased by approximately 100% in a separate group of dogs. These effects of adenosine on DFT were abolished when the dogs were autonomically denervated, suggesting that the deleterious effects of adenosine on DFT are due to its antiadrenergic mechanism of action. These data indicate that adenosine release during VF can markedly increase DFT. Since adenosine myocardial release during VF is time dependent, it is likely that adenosine plays a significant role in mediating the increase in threshold that is dependent on the duration of VF.
Adenosine↗
The role of the sympathetic nervous system in the regulation of ultradian rhythms in urine excretions.
The effects of alpha and beta adrenoreceptors blockade and surgical kidney denervation on ultradian rhythmicity in urine excretion were investigated in four dogs. Pharmacological treatments and surgical denervation of the kidneys suppressed the ultradian rhythmicity in urine flow but did not completely eliminate the ultradian rhythms in urinary osmolality and in electrolyte concentrations. These findings suggest that the autonomic nervous system plays a major role in the regulation of the ultradian rhythms in water excretion in dogs. The partial persistence of ultradian rhythms in urine osmolality and electrolyte concentrations after autonomic denervation supports the assertion that the ultradian rhythms in solute concentrations are regulated by different mechanisms to those of water excretion, suggesting the possible involvement of a multioscillatory system.
Activity Cycles↗
Bladder and sexual function after surgery for rectal cancer.
Bladder function and sexual potency were studied before and after surgery for rectal carcinoma. Urinary voiding after postoperative removal of indwelling catheter was impaired in seven of 22 men, leading to prostatic surgery in four. Two years later, eight of 16 men reported disturbed voiding, but no significant changes were found in bladder capacity, residual volume, flow rate, or detrusor pressure. Sexual potency was reduced in five of ten men, in one with retrograde ejaculation; and three did not achieve erection. Objective postoperative bladder disturbance was surprisingly rare. Symptoms of denervation were more commonly attributable to sympathetic rather than parasympathetic lesions, possibly as a result of more energetic dissection in the anteroposterior plane than along the lateral pelvic walls. No patient had total autonomic denervation. Wide indications are advocated for prostatic resection in patients who have prostatic symptoms in association with surgery for rectal carcinoma.
Aged↗
Abnormal chemoreceptor response to hypoxia in patients with tabes dorsalis.
Nine patients with tabes dorsalis and one patient with diabetic autonomic neuropathy were subjected to hypoxia to test the integrity of their carotid chemoreceptors. Ventilation and pulse rate changes were monitored and compared with those of a group of normal subjects of comparable age and sex. Four patients had a completely negative response to hypoxia, and the changes in ventilation in the group of patients as a whole were significantly less than in the control subjects. The results indicate that some patients with autonomic denervation are unable to adjust their respiratory system in response to hypoxia.
Aged↗
Long-term outcome of laparoscopic ventral rectopexy for total rectal prolapse.
BACKGROUND: Postoperative constipation is a common problem with most mesh suspension techniques used to correct rectal prolapse. Autonomic denervation of the rectum subsequent to its complete mobilization has been suggested as a contributory factor. The aim of this study was to assess the long-term outcome of patients who underwent a novel, autonomic nerve-sparing, laparoscopic technique for rectal prolapse. METHODS: Between 1995 and 1999, 42 patients had laparoscopic ventral rectopexy for total rectal prolapse. The long-term results after a median follow-up of 61 (range 29-98) months were analysed. RESULTS: There were no major postoperative complications. Late recurrence occurred in two patients. In 28 of 31 patients with incontinence there was a significant improvement in continence. Symptoms of obstructed defaecation resolved in 16 of 19 patients. During follow-up, new onset of mild obstructed defaecation was noted in only two patients. Symptoms suggestive of slow-transit colonic obstipation were not induced. CONCLUSION: Laparoscopic ventral rectopexy is an effective technique for the correction of rectal prolapse and appears to avoid severe postoperative constipation. The ventral position of the prosthesis may explain the beneficial effect on symptoms of obstructed defaecation.
Adult↗
["Single potential analysis of cavernous electric activity" (SPACE). Findings before and after surgical dissection of the cavernous nerves within the scope of radical prostatectomy].
Single potential analysis of cavernous electric activity (SPACE) is said to give information on the integrity of the central and peripheral parts of the autonomic nervous system insofar as it is involved in erectile function. A total of 30 patients who underwent radical prostatectomy with simultaneous severance of the cavernous nerves as treatment for locally advanced cancer were investigated by SPACE before and after the operation. The findings were compared to the those recorded on two different dates in 20 age-matched men who had not undergone surgery and in whom there was no evidence of any lesion of the autonomic nervous system. Even in this control group, few reproducible results were found. Nevertheless, with reference to the items "number of wedges" (i.e. monophasic elements with amplitudes of 25-100 microV) and "maximum amplitudes" of SPACE potentials there was a more than change correlation of the values on the two test dates, which was not found in the prostatectomy group. Although this difference between the two groups investigated was statistically significant, these findings cannot be interpreted as an effect of autonomic denervation of the cavernous bodies. This is attributed to the fact that the postoperative results in the prostatectomy group were more similar to the findings in the control group than to the preoperative measurements taken while the autonomic innervation was still intact. Therefore, our investigations lead us to conclude that routine application of SPACE as a direct check on the integrity of the autonomic nerve fibres involved in erectile dysfunction is not justified at present.
Adult↗
Heart rate variability: an important new risk factor in patients following myocardial infarction.
After acute myocardial infarction, cardiac autonomic, and particularly parasympathetic, activity decreases, followed by a gradual return toward normal over the next few weeks and months. The easiest measurable index of autonomic activity is heart rate variability, which can be assessed in a number of different ways. Where heart rate variability is low after myocardial infarction, long-term survival is considerably reduced, independent of other known risk factors. This may be caused by patchy autonomic denervation, rendering the heart more susceptible to potentially fatal arrhythmias. Prophylactic drug therapy might reduce mortality in patients with low heart rate variability.
Autonomic Nervous System↗
Single potential analysis of cavernous electrical activity. Four years' experience in more than 500 patients with erectile dysfunction.
Since the recent introduction of cavernous electromyography by Gerstenberg and Wagner, a new too for the study of erectile dysfunction in man is available. The refinement of this method, single potential analysis of cavernous electrical activity (SPACE), offers a straightforward approach to the diagnosis of cavernous autonomic neuropathy and smooth muscle myopathy by minimal invasive means. SPACE was done in more than 500 consecutive patients with erectile dysfunction and in 85 normal control subjects. With increasing experience the methodology was refined with respect to the used hardware as well as cut-off frequencies. In normal control subjects, SPACE showed a reproducible regular activity with potentials of low frequency and electrical silence inbetween. The potentials were synchronous throughout the cavernous bodies. In patients with peripheral autonomic denervation, asynchronous potentials with higher frequencies and irregular shape were found. Normal and abnormal potentials were found in patients with upper spinal cord lesions. Recordings obtained with surface electrodes showed similar characteristics when compared with recordings obtained with needle electrodes. Recent studies show that SPACE provides independent information about the autonomic and myogenic intactness of the cavernous tissue. Currently, a computerized expert system and a graded classification for easier interpretation is being developed with first results. We conclude that cavernous electrical activity can be recorded. SPACE is a reproducible diagnostic tool for erectile dysfunction.
Action Potentials↗
Is diabetic heart muscle disease related to cardiac ischemia or autonomic neuropathy?
Whether diabetic heart muscle disease is related to cardiac ischemia or autonomic neuropathy was investigated employing thallium-201 and [123I]meta-iodobenzylguanidine (MIBG) myocardial scintigraphy. Among ischemic hearts, displayed by TI201 scintigraphy, a distinctly dilated and hypokinetic left ventricle could not be detected. In autonomically denervated hearts, however, well demonstrated by MIBG imaging, distinct dysfunction was found. But, even in these hearts, interacting effects of some concomitant complications could not be excluded.
3-Iodobenzylguanidine↗
The enigma of autonomic failure in diabetes.
The extent of autonomic failure in diabetes and the damage that results both in terms of structure and function is seldom realised. This article focuses on the consequences of autonomic denervation of several different forms of smooth muscle, notably those of arterial wall, vas deferens, stomach, iris and bronchial wall. The clinical implications of these changes are described, in particular the problems arising from vascular (and vas deferens) calcification and abnormalities of vascular reactivity; insulin-induced postural hypotension and the splanchnic circulation; the anaemia of autonomic neuropathy from failure of erythropoietin production; gastromyopathy as a cause of gastroparesis; iritis as a symptom related to diabetic autonomic neuropathy (DAN); the concept of an autoimmune basis for DAN; and failure of bronchial reactivity and respiratory arrests in DAN. The importance of clinical observation leading to clinical experiment and research, together with the stimulation of ideas by collaboration with clinical colleagues in other disciplines is emphasised throughout.
Autonomic Nervous System Diseases↗
Cardiac autonomic neuropathy and its correlation with QTc dispersion in type 2 diabetes.
This study was conducted on 50 patients of diabetes mellitus type 2 and 20 healthy controls to correlate severity of diabetic cardiac autonomic neuropathy with QTc interval and QTc dispersion. Five standard cardiovascular response tests were carried out (i.e. Valsalva ratio, expiration-inspiration ratio, immediate heart rate response to standing, fall of systolic blood pressure on standing and sustained hand grip test) to determine the severity of cardiac autonomic neuropathy by scoring system. QTc dispersion was determined by subtracting heart rate-corrected minimum QTc interval (QTc min) from maximum QT interval (QTc max) from standard electrocardiogram. Severity of cardiac autonomic neuropathy strongly correlated with QTc dispersion (r = 0.760; p = 0.0001). Correlation of severity of cardiac autonomic neuropathy with QTc max and QTc mean was also found but weaker than with QTc dispersion (r = 0.663, r = 0.542, p = 0.0001 each) and no correlation was found with QTc min (r = 0.177; p = 0.17). This shows that QTc dispersion is a better predictor of cardiac autonomic neuropathy than any of above three QTc intervals. QTc max, QTc mean and QTc dispersion were significantly higher (p < 0.001) in diabetics with autonomic neuropathy (450 +/- 23, 423 +/- 22 and 57 +/- 12 msec; n = 30) than without neuropathy (407 +/- 14, 397 +/- 15 and 20 +/- 7 msec; n = 20) and control subjects (408 +/- 20, 399 +/- 19 and 19 +/- 7 msec; n = 20) but QTc min remained same in the three groups (393 +/- 21, 387 +/- 12, 388 +/- 19 msec, respectively) (p > 0.05). Correlation of QTc dispersion was stronger with QTc max (r = 0.781; p < 0.001) than QTc mean (r = 0.625; p = 0.001) but not with QTc min (r = 0.097; p = 1.0) which suggests that regional increase in QT interval due to regional autonomic denervation leads to increased QTc dispersion. Thus, QTc dispersion is a sensitive, non-invasive, simple and cost-effective predictor of cardiac dysautonomia.
Adult↗
Age-dependent effect of pituitary transplants on immune responses in rat submaxillary lymph nodes: modulatory effect of the autonomic nervous system.
An anterior pituitary was grafted into the breast muscles of male rats on day 5, or under the kidney capsule on day 30 or 60 of life. At the 70th day of life (rats operated at the 5th or 30th day) or at the 100th day of life (rats operated at the 60th day), rats were injected subcutaneously with Freund's complete adjuvant, being killed 2 days later. Rats pituitary-grafted at the 30th day showed a greater hyperprolactinemia than rats grafted at the 5th or 60th day. Submaxillary lymph node natural killer (NK) activity decreased in neonatally pituitary-grafted rats and increased in rats grafted at the 30th or 60th day of life, while lymph node cellularity decreased in rats grafted at the 30th or 60th day. In the case of lipopolysaccharide (LPS)-and concanavalin A (Con A)-induced cell proliferation in lymph nodes, the only significant factor detected was age of transplantation, the effect being less evident in older animals. To examine whether the autonomic denervation of submaxillary lymph nodes affected immune responses in pituitary-grafted rats, animals were subjected to a unilateral superior cervical ganglionectomy (Gx) and/or a parasympathetic decentralization (Dc; by chorda tympani section), 10 days before immunization with Freund's adjuvant. A unilateral Gx blunted the stimulation of lymph node NK activity in rats receiving a pituitary transplant at the 30th or 60th day, but not at the 5th day. Only in sympathetically denervated lymph nodes a significant effect of pituitary transplants on LPS mitogenic effect was found, with significantly less effect of LPS in rats pituitary-grafted at the 5th or 30th day of life. Regarding Con A, a unilateral Gx or unilateral Gx plus Dc uncovered a significant depressive effect of pituitary transplants with a significantly smaller Con A mitogenic effect at each studied age in ipsilaterally Gx lymph nodes, and at 30 and 60 days of age in ipsilaterally Gx plus Dc lymph nodes. Pituitary grafts augmented Con A- induced proliferation in submaxillary lymph nodes at the 5th day of life while they decreased it at the 60th day of life. Pituitary transplants augmented cellularity at the sympathetically denervated lymph nodes and decreased it at the contralateral sham-operated side. Pituitary transplants also diminished lymph node cellularity at the Dc side, the effect being significant in rats transplanted at the 30th day of life. The results are compatible with age-dependent, inhibitory as well as promoting activities of hyperprolactinemia on immune responses in submaxillary lymph nodes, depending in part on intact autonomic nerves.
Age Factors↗
Detection of subclinical autonomic neuropathy in constipated patients using a sweat test.
Chronic idiopathic constipation may be the result of an autonomic neuropathy. This hypothesis was tested in 23 constipated patients and 17 age matched controls, using the acetylcholine sweat spot test devised to test autonomic integrity in diabetes. Acetylcholine (0.01%) was injected in the dorsum of the foot painted with a mixture of starch and iodine. Active sweat glands appeared on the surface of the skin as small black dots which were photographed and counted, using a grid with 60 subareas. Two measurements were made: the number of dots per unit subarea (sweat spot test score) and the % number of abnormal subareas (with less than six spots). These two parameters were correlated. The median sweat spot test score was 9.53 in patients and 13.92 in controls (p = 0.0001), the receiver operating characteristic curve showing that a score of 12 delimited normal and abnormal subjects. Increasing age was correlated with a low score in patients, probably because of prolonged symptoms. Seventy per cent of patients and one control had a borderline or abnormal number of subareas. These results suggest that idiopathic constipation is associated with a degree of autonomic denervation. The sweat spot test is an easy, inexpensive method to test this hypothesis and deserves a place in the clinical assessment of slow transit constipated patients.
Acetylcholine↗
A case of prolonged hypotension following intravenous guanethidine block.
A 25-year-old female developed causalgia following a nerve injury in the left hand, and this was treated successfully with a series of intravenous guanethidine blocks. However, after the 13th block, systolic arterial blood pressure decreased to 60 mmHg and remained low (80 mmHg) for one week. Accumulation of guanethidine at the sympathetic nerve ending, resulting in autonomic denervation, might be the underlying mechanism of the prolonged hypotension. Treatment was conservative; however, the use of tricyclic antidepressants and sympathomimetic amines to restore the blood pressure to a normal level can be considered with appropriate caution.
Adult↗
Reversible left ventricular dysfunction (takotsubo cardiomyopathy) with deep negative T waves due to possible cardiac sympathetic denervation.
A case of characteristic left ventricular contraction disorder representing takotsubo cardiomyopathy after exercise is reported. A 58-year-old Japanese woman with no history of cardiac disease was admitted for chest oppression after exercise. A diagnosis of myocardial infarction was suspected because of her symptom, and the electrocardiographic and echocardiographic findings. Coronary angiography revealed normal arteries, while left ventriculography demonstrated asynergy with apical akinesis and basal hyperkinesis. Deep negative T waves were observed on the electrocardiogram on the second hospital day and sustained for over a month. Repeated measurements of heart rate viability and 123I-metaiodobenzylguanidine scintigraphy showed transient dysfunction of the cardiac autonomic nervous system. From these findings, it was concluded that cardiac autonomic denervation plays a pivotal role in the etiology of takotsubo cardiomyopathy.
Cardiomyopathies↗