Hirschsprung's disease: catecholamine content, alpha-adrenoceptors, and the effect of electrical stimulation in aganglionic colon

In order to assess abnormalities in the adrenergic mechanism in the intestine of Hirschsprung's disease, catecholamine concentrations, alpha-adrenoceptors, and the effect of electrical field stimulation were examined in aganglionic segments of colon or rectum. The aganglionic segment had a higher concentration of norepinephrine, assayed with high performance liquid chromatography with an electrochemical detector, whereas concentrations of epinephrine or dopamine were similar in normal and pathological segments. In four patients with extensive aganglionosis, the norepinephrine concentration in aganglionic colon segments decreased progressively in descending, transverse, and ascending colon. The tissue content of alpha-adrenoceptors and their affinity assayed from the specific binding of [3H]dihydro-alpha-ergocryptine appeared similar in normal and aganglionic segments of the rectosigmoidal colon. Electrical field stimulation of normal rectosigmoidal colon segments caused relaxation at low frequencies and contraction at a very high frequency. Relaxation was not abolished by blocking concentrations of propranolol or phentolamine. In aganglionic segments, the predominant response to electrical field stimulation was contraction, which was inhibited by either atropine or tetrodotoxin. These results indicate that an alpha-adrenergic system and cholinergic innervation apparently exist in aganglionic colon segments and that dysfunction of the colon appears to result from lack of a nonadrenergic inhibitory system.     

Study on function of aganglionic colon musculature of Hirschsprung's disease murine model

This study examined the function in vitro of aganglionic colon musculature in mice with hereditary aganglionosis--a strain of animals used as a model of Hirschsprung's disease. Double sucrose gap recordings from the muscle strips of both normal and aganglionic colon showed bursts of spike potentials with muscle contraction. Intracellular recordings of the membrane potentials of the circular muscle cells of normal, aganglionic and oligo-ganglionic colon had no statistical difference. Microelectrode recordings from the circular muscle cells of normal siblings, in the presence of nifedipine, irregular ongoing fluctuations in membrane potential, which were abolished by tetrodotoxin and reduced by d-tubocurarine or apamin. The fluctuations were less effected by atropine. These observations suggest that there is ongoing inhibitory neural activity to the circular smooth muscle of normal colon. These ongoing fluctuations were not recorded from the cells of aganglionic and oligo-ganglionic colon of affected animals. Although transmural stimulation of the intrinsic nerves produced cholinergic excitatory and inhibitory junction potentials in normal colon, no junction potentials were evoked by transmural stimulation in aganglionic colon. It was concluded that the ongoing tonic inhibitory activity may contribute to the compliance of the normal mouse colon and lack of the compliance may affect functional intestinal obstruction of the aganglionic colon in Hirschsprung's disease.     

Hirschsprung's disease: a comparison of the nervous control of ganglionic and aganglionic smooth muscle in vitro

Specimens from aganglionic (constricted) and ganglionic (dilated) gut were obtained from nine patients with Hirschsprung's disease. Transmural nerve stimulation of ganglionic smooth muscle in vitro evoked an initial relaxation followed by a contraction. This contraction was reduced but not abolished by atropine and it was further reduced by substance P antagonists. Guanethidine did not affect the electrically evoked responses. In aganglionic smooth muscle, an atropine-sensitive contraction but no initial relaxation was registered. Tetrodotoxin abolished all responses to electrical stimulation in both ganglionic and aganglionic specimens. Application of carbachol or substance P produced contraction and the adrenergic agonist isoprenaline or vasoactive intestinal peptide produced relaxation in ganglionic as well as aganglionic specimens. Two other gut neuropeptides, neuropeptide Y and galanin, were without effect. The results do not indicate a different receptor set up in ganglionic v aganglionic gut. The results are compatible with a lack of noncholinergic nonadrenergic inhibitory neurons in the aganglionic gut.     

Effect of stimulation of the tooth pulp on gastrointestinal motility in rabbits

Effects of electrical stimulation of the inciser tooth pulp on the gastrointestinal motility were investigated in the rabbit anesthetized with urethane and chloralose. Pulpal Stimulation caused an excitatory or an inhibitory effect in the gastric body and antrum and the ducodenum. After bilateral splanchnicotomy the excitatory response to the pulpal stimulation was reinforced or the inhibitory response converted to the excitatory response. An additional cervical vagotomy abolished the excitatory and inhibitory response. Atropine diminished the spontaneous efferent discharges of vagal gastric branch (VGB) and abolished the excitatory and inhibitory response to stimulation of the pulp and the inferior alveolar nerve. This agent also blocked the potentials of the VGB evoked by afferent stimulation of the inferior aveolar nerve. Hexamethonium bromide abolished the excitatory and inhibitory responses to the pulpal stimulation but did not affect spontaneous discharges and increased discharges of the VGB to pulpal stimulation. Morphine produced decreased rate of the spontaneous discharge of the VGB and abolished increased rate of discharges of the VGB as well as the gastrointestinal responses to pulpal stimulation. It is concluded from these results that the afferent impulses caused by pulpal stimulation and the inferior alveolar nerve 'reflex'ly activate the vagal motor nuclei in the medulla oblongata and the sympathetic splanchnic nuclei in the thoracic segments through the trigeminal nerve: The vagus nerves produced the excitatory response in the gastrointestinal motility, while the splanchnic nerves caused the inhibitory response. It was supposed that sites of action of atropine and morphine is not in peripheral site, but in the central nerves site.     

Responses of muscle strips from the internal anal sphincter in Hirschsprung's disease to drugs and electrical field stimulation

Responses of isolated muscle strips from the rat and the dog internal anal sphincter (IAS) to drugs and electrical field stimulation (EFS) were investigated in vitro for the purpose of clarifying a manner of neural control of IAS. Also, responses of muscle strips from IAS of the patients with Hirschsprung's disease were compared with those of muscle strips from human control IAS. Muscle strips from the dog and human IAS as normal control showed contractions to norepinephrine (NE), which were abolished in the presence of phentolamine and relaxations to isoproterenol. EFS (less than 1 msec) induced relaxations of the muscle strips. These responses to EFS were not affected by either one of phentolamine, propranolol and atropine but were inhibited by tetrodotoxin. Muscle strips from IAS in Hirschsprung's disease contracted to both NE and EFS, the responses of which were abolished in the presence of phentolamine. But no relaxation to EFS of muscle strips from IAS in Hirschsprung's disease was observed. These findings revealed that normal IAS is pharmacologically innervated by alpha-adrenergic excitatory nerve, beta-adrenergic inhibitory nerve and non-adrenergic, non-cholinergic inhibitory nerve and suggested that IAS in Hirschsprung's disease is also affected by alpha-adrenergic excitatory nerve but inhibitory neural control is absent.     

Role of nitric oxide in the internal anal sphincter of Hirschsprung's disease

It is not clear what contribution the internal anal sphincter (IAS) makes to the impaired motility observed in patients with Hirschsprung's disease (HD). Nitric oxide (NO) has recently been shown to be a neurotransmitter in the nonadrenergic noncholinergic (NANC) inhibitory nerves in the human gut. To clarify the physiologic significance of NO in the IAS of HD (aganglionosis), we investigated the enteric nerve responses on lesional (aganglionic) and normal IAS muscle strips above the dentate line. Lesional and normal IAS muscle strips above the dentate line were derived from patients with HD (10 cases) and patients who underwent rectal amputation for low rectal cancer (12 cases). A mechanographic technique was used to evaluate in vitro muscle responses to electrical field stimulation (EFS) before and after treatment with various autonomic nerve blockers, N(G)-L-nitroarginine, and L-arginine. The following results were obtained: (1) Cholinergic nerves are mainly involved in the regulation of enteric nerve responses to EFS in the normal IAS. (2) The aganglionic IAS of patients with HD was more strongly innervated by cholinergic nerves than the normal IAS (p < 0.05). (3) NANC inhibitory nerves were found to act on the normal IAS but had no effect on the enteric nerves in patients with aganglionosis. (4) NO was found to act on normal IAS, but no effect was observed in the aganglionic IAS. These findings suggest that innervation of the cholinergic nerves and a loss of NO mediation of NANC inhibitory nerves play an important role in the impaired motility observed in the IAS with HD.     

Functional innervation patterns in the corpus spongiosum and glans in the dog

The neural control of smooth muscle cells in the corpus spongiosum, helicine artery and bulbus glandis of the dog was investigated in relation to the mechanism involved in erection, using isometric tension recording and micro-electrode methods. In the corpus spongiosum, field stimulation evoked twitch-like contractions followed by relaxations. These relaxations were enhanced and prolonged by neostigmine and partly suppressed by atropine. Guanethidine abolished the twitch-like contractions and increased muscle tone. The relaxations observed after pre-treatment with guanethidine were abolished by tetrodotoxin (TTX), thereby indicating that these muscles are innervated by adrenergic excitatory, cholinergic and non-adrenergic non-cholinergic inhibitory nerves. In the helicine artery and bulbus glandis, field stimulation evoked contractions and these contractions were abolished by guanethidine or TTX, indicating that these muscles are innervated by adrenergic excitatory nerve fibres. After pre-treatment with guanethidine and atropine, muscle relaxation appeared in response to field stimulation in the helicine artery but not in the bulbus glandis, indicating that the helicine artery in the corpus spongiosum is also innervated by non-adrenergic non-cholinergic inhibitory nerves in addition to the excitatory adrenergic nerves. In the smooth muscle cells of the corpus spongiosum, slow potential changes were correlated with spontaneous contractions and field stimulation evoked excitatory or inhibitory junction potentials. The neural mechanism involved in erection is discussed in relation to the topical difference in the autonomic innervation patterns in the corpus spongiosum, helicine artery and bulbus glandis.     

Electrically evoked activity in the human external anal sphincter

Following electrical stimulation of perianal skin, short latency evoked electromyographic (EMG) responses from the external and sphincter have been interpreted as the electrophysiological correlate of the anal reflex. Delayed responses in patients with idiopathic faecal incontinence have been interpreted as evidence for denervation of the external anal sphincter. Electrically evoked responses were studied in normal subjects, either before and during spinal anaesthesia (n = 8), or before and during competitive neuromuscular blockade (n = 4), instituted for operative purposes. Short latency responses persisted unchanged in either latency or duration during spinal anaesthesia whereas long latency responses were completely abolished. Both short and long latency responses were abolished during competitive neuromuscular blockade. Short latency responses are not spinal reflex in nature, but due to stimulus activation of alpha-motoneuronal terminal branches. Delayed responses in incontinent patients cannot be interpreted as evidence for pudendal neuropathy. Long latency (i.e. greater than 40 ms) responses demand a functional sacral spinal cord and represent the true anal reflex. Their wide range of latency in normal subjects suggests this measurement will be of little use in confirming the presence or absence of pudendal neuropathy, and that other measures of neuropathy may be more appropriate.     

Pudendal nerve stimulation evokes reflex bladder contractions in persons with chronic spinal cord injury

AIMS: Although electrical stimulation of the pudendal nerve has been shown to evoke reflex micturition-like bladder contractions in both intact and spinalized cats, there is little evidence to suggest that an analogous excitatory reflex exists in humans, particularly those with spinal cord injury (SCI). We present two cases where electrical activation of pudendal nerve afferents was used to evoke excitatory bladder responses. SUBJECTS AND METHODS: A percutaneously placed catheter electrode was used to electrically stimulate the pudendal nerve trunk in two males with SCI. The response was quantified with recorded changes in detrusor pressure and EMG activity of the external anal sphincter. RESULTS: In both individuals, frequency specific (f = 20-50 Hz) activation of the pudendal nerve trunk evoked excitatory bladder contractions that also depended on the stimulus amplitude and bladder volume. CONCLUSION: The results suggest that selective activation of the perineal branches of the pudendal nerve may further augment the excitatory reflex evoked by electrical stimulation.     

The role of nitrergic system on the contractility of colonic circular smooth muscle in Hirschsprung's disease.

The contribution of nitrergic tone on the contractility of colonic smooth muscle in Hirschsprung's disease (HD) was investigated. METHODS: Ganglionic and aganglionic bowel specimens were taken from 8 patients with HD during pull-through operations and electrical field stimulation (EFS)-induced isometric contractions of the circular smooth muscle were recorded in vitro. Isolated circular muscle strips prepared from colonic segments of sex- and age-matched patients (n = 3) who underwent surgery for nonmotility-related colonic diseases formed the control group. Statistical analysis was performed by two way analysis of variance and unpaired Student's ttest. RESULTS: The amplitude of spontaneous rhythmic activity was lower in aganglionic segments than in ganglionic ones. The amplitudes of contractile responses were significantly greater in aganglionic segments. In ganglionic preparations, N(omega)-nitro-L-arginine (L-NNA) addition into the medium increased the contractile responses to the level of aganglionic preparations. This increase was completely blocked by L-arginine application. Neither L-NNA nor L-arginine produced any change in aganglionic segments. A relaxation phase was detected in both ganglionic and aganglionic segments. In ganglionic preparations, this relaxation phase was completely inhibited by L-NNA and restored by L-arginine, whereas no effect was detected in aganglionic ones. Responses obtained from the control group were similar to the ganglionic segments of HD patients. CONCLUSIONS: In normal colon and as well as in ganglionic segments of HD, the evoked contractile activity and relaxations are under the tonic influence of the nitrergic system. Aganglionic segments totally lack the nitrergic activity in both evoked contraction and relaxation responses, while still maintaining an inefficient relaxation capacity under unknown mechanisms.     

Nerve mediated responses to drugs and electrical stimulation in aganglionic muscle segments in Hirschsprung's disease

The activity of isolated muscle strips from normal and aganglionic human large bowel was studied in vitro. The intrinsic nerves were stimulated electrically and by nicotinic agonists. The ganglionic preparations displayed a strong inhibitory response due to the release of both norepinephrine and a noncholinergic, nonadrenergic inhibitory neurotransmitter. In the aganglionic strips (obtained from patients with Hirschsprung's disease), nerve activation tended to evoke contraction, apparently due to enhancement in the release of acetylcholine. At the same time, the release of norepinephrine appeared to be less than normal. A particularly interesting finding in the aganglionic muscle strips was the presence of a substantial inhibitory response due to the release of a noncholinergic, nonadrenergic substance. These results provide further evidence for the importance of the innervation of the aganglionic segment in Hirschsprung's disease.     

An in vitro pharmacological study of the human trigone--a site of non-adrenergic, non-cholinergic neurotransmission

Muscle strips from the human detrusor and trigone were studied in vitro. The detrusor muscle contracted strongly to both cholinergic receptor stimulation with carbachol and to electrical field stimulation. There was no evidence of atropine resistance in the detrusor strips. The superficial trigone responded maximally to alpha-adrenergic receptor stimulation but also produced a significant cholinergic response. Intramural nerve stimulation in the presence of both atropine and phentolamine produced a residual non-adrenergic, non-cholinergic (NANC) response of 40% of its maximum at 5 Hz. Electrical stimulation, particularly at the lower frequencies of stimulation, produced relaxation responses in 40% of the superficial trigonal muscle strips. These relaxations were not blocked by atropine, phentolamine or propranolol, but were abolished by tetrodotoxin. The possible role of the cholinergic "input" to the superficial trigone and the importance of the NANC excitatory and inhibitory innervation in preventing vesico-ureteric reflux and and in aiding bladder neck opening is discussed.     

Adrenergic control of the internal anal sphincter is abnormal in patients with idiopathic faecal incontinence

There is histological and functional evidence that the internal anal sphincter is abnormal in patients with idiopathic faecal incontinence. The in vitro responsiveness of the internal anal sphincter to noradrenaline (an important sympathetic neurotransmitter) and electrical field stimulation (known to stimulate the intrinsic innervation) has been studied. Muscle strips from eight patients with incontinence undergoing postanal repair and five controls undergoing resection for low rectal carcinoma were studied. The contraction-response curves for noradrenaline were significantly different, and the EC50, the concentration required to produce 50 per cent of maximum contraction, was higher in incontinent patients (P less than 0.001). Electrical field stimulation produced initial contractions in four of the control group which were blocked by phentolamine. This contraction was not present in the incontinent patients (P less than 0.01). These results indicate an abnormality in the adrenergic innervation of the internal anal sphincter in patients with idiopathic faecal incontinence.     

Functional response to vasoactive intestinal peptide in piebald lethal mice

Diminished concentrations of the gut neuropeptide, vasoactive intestinal peptide (VIP), have been measured by radioimmunoassay in man and mouse models of Hirschsprung's disease. This in vitro study was designed to ascertain the functional response to VIP in aganglionic colon. Seven piebald lethal (PLM) mice with histologically verified aganglionosis and seven normal littermates (NLM) were sacrificed. Distal colonic segments were placed in standard oxygenated tissue baths and responses to electrical field stimulation (EFS), acetylcholine (ACh), and VIP recorded and analyzed by a motility index (MI). Aganglionic colonic tissues from PLM exhibited marked basal contractile activity in contrast to NLM (MI = 19.5 +/- 2.0 SEM v 6.5 +/- 3.6 SEM, P less than .01). In NLM tissues, VIP reduced the MI to ACh challenge by 49% (P less than .01), while in PLM tissues, a nonsignificant 22% reduction was observed. VIP blocked the response to EFS in NLM tissues, while no response was elicited to EFS in PLM tissues. An in vitro deficit in the VIP inhibitory response to ACh challenge is apparent in PLM with distal colonic aganglionosis. The increased basal activity and reduction in responsiveness to VIP, observed in the PLM tissues, support a generalized reduction in the function of the inhibitory innervation of the aganglionic colon.     

External anal sphincter responses after S3 spinal root surface electrical stimulation

AIMS: The aim of this study is to present the normative data of direct and reflex motor anal sphincter responses, simultaneously evoked by S3 surface electrical stimulation. By this method, it is possible to test the functional integrity of the nervous pathways activated during sacral neuromodulation (SNM). METHODS: Twenty healthy subjects were studied. Motor-evoked potentials (MEPs) were recorded by concentric needle electrode from external anal sphincter (EAS). Electrical stimulation was applied by means of a bipolar surface electrode over the S3 right or left sacral foramina. RESULTS: Direct (R1) and reflex responses (R2 and R3) were found at latencies of 6.98, 25.12, and 50.31 msec, respectively. The two first responses were recorded in all the cases; the last response is steadily recorded in 17 out of 20 subjects. CONCLUSIONS: Our data can serve as reference values for future study in patients with pelvic floor dysfunction. EAS responses following S3 percutaneous electrical stimulation can represent a useful aid in the selection of candidates to SNM.     

Surgical treatment of total colonic aganglionosis: efficacy of aganglionic patch enteroplasty in the rat

This study evaluates ileo endorectal pull-through (IEP) with and without an aganglionic colon patch in an experimental rat model for the surgical treatment of total colonic aganglionosis (TCA). Animals were randomly assigned to Group 1 (no patch, No. = 6), Group 2 (right colon patch, No. = 8), Group 3 (transverse colon patch, No. = 7), Group 4 (left colon patch; No. = 6), sham operation (SH, No. = 6), and unoperated controls (UC, No. = 10). Change in percent body weight at 4 weeks after operation was -30.9 +/- 3.68% in Group 1, +5.1 +/- 1.67% in Group 2, -3.4 +/- 3.96% in Group 3, -1.8 +/- 4.17% in Group 4, and +12.7 +/- 1.54% in SH (Group 1 v other groups: P less than .001). Restoration of initial body weight occurred in 100% in Group 2 and SH (8/8 and 6/6, respectively), 50% in Group 4 (3/6), 42.9% in Group 3 (3/7), and 0% in Group 1 (0/6). Transit time (stomach to anus) was significantly shorter in Group 1. All rats in patched groups had a prolonged transit time compared with Group 1. Manometric studies in IEP rats showed favorable anal canal pressures, which were slightly lower than SH and UC. Water and Na+ absorption were significantly greater in patched groups. Rats with a right colon patch (Group 2) showed slightly greater absorption at 4 weeks. These data suggest that an aganglionic colon patch may be an important adjunct in the surgical treatment of TCA.     

Is preserving the entire aganglionic colon reasonable in the surgical treatment of total colonic aganglionosis?

Clinical reports describe an increased incidence of severe enterocolitis in infants with total colonic aganglionosis (TCA) following the Martin extended Duhamel procedure using the entire aganglionic colon. This study evaluates the efficacy of this procedure in an experimental model of TCA in comparison with an antimesenteric aganglionic colon patch in rats. TCA was produced by serosal application of 0.1% benzalkonium chloride in 18 Sprague-Dawley rats (250 g). Five additional rats served as operated controls. Ileoanal pull-through was performed in 18 TCA rats, in conjunction with the Martin extended Duhamel procedure using the entire colon in six rats, with an aganglionic colon patch in nine (using the right [3 rats], transverse [3 rats] and left [3 rats] colon), and without other procedures in three rats. Animals were evaluated for survival, weight change, food intake, stool consistency and volume, barium enema, complete blood cell count (CBC), total protein, and serum electrolytes at 4 and 12 weeks. Survival was 83% (5/6) rats with the Martin procedure, 100% in the nine rats with various colon patches, zero in three rats with ileoanal pull-through alone, and 100% in controls. Rats with the Martin procedure gained 2.2 +/- 3.27% of preoperative weight, while controls gained 11.2 +/- 0.52% at 4 weeks. All other rats showed an early weight loss. At 12 weeks, right and transverse colon patched rats had weight gain. Blood count and laboratory studies were similar in each group. Barium enema showed rapid transit in rats with ileoanal pull-through, and slower transit in rats with colon patches or the Martin procedure.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hirschsprung's disease with skip area (segmental aganglionosis)

Hirschsprung's disease is characterized by a single aganglionic segment of colon extending distally to the anal margin. Well documented reports of segmental aganglionosis have been rare. We report a case of segmental aganglionosis in which there were two distinct aganglionic segments resected. The entire transverse colon between the two aganglionic segments was normally ganglionated, preserved, and utilized and functions in a normal fashion.     

Differential effects of sacral anterior root stimulation on anal sphincter and colorectal motility in spinally injured man

The motility responses of the sigmoid colon, rectum and external anal sphincter to sequential electrical stimulation of the anterior sacral roots (S2, S3 and S4) were studied in five patients with traumatic spinal cord injury. Identical and reproducible results were obtained. S2 stimulation provoked isolated low-pressure colorectal contractions. S3 stimulation initiated high-pressure colorectal motor activity which appeared peristaltic and was enhanced with repetitive stimuli. This response appeared to be frequency-dependent. S4 stimulation increased colonic and rectal tone. External sphincter activity was stimulated in increasing order from S2 to S4. These observations directly elucidate the central control of colorectal motility and may have implications in the treatment of severe constipation following spinal injury.