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Histological appearances of the nerves of the bladder in patients with denervation of the bladder after excision of the rectum.

Two groups of patients who developed denervation of the bladder after excision of the rectum for carcinoma have been studied by histological examination of bladder biopsies. The groups were compared with a group of control patients of a similar age. One group with denervation of the bladder was studied soon after (7 weeks) and the other group in the long term (10 months) after operation. Bladder biopsies were stained for acetylcholinesterase, catecholamines and connective tissue. Tissue was also processed for electron microscopy. In control patients, the ratio of cholinesterase positive nerves to the number of smooth muscle nuclei (24:100) was significantly greater than in patients with denervation of the bladder studied soon after operation (2.5: 100; P less than 0.01). Appearances consistent with degenerate nerve terminals were observed on electron microscopy in these patients. No increase in the density of adrenergic nerves was observed in either group of patients with denervation of the bladder. In the long term, a greater density of cholinergic innervation was noted compared with patients studied soon after operation (P less than 0.05). In addition, nerve terminals, similar in appearance to those of control patients, were observed on electron microscopy. The findings in patients with denervation of the bladder studied in the long term after operation are consistent with partial regeneration of autonomic nerves. They suggest that, whilst histological examination of bladder biopsies may be useful soon after excision of the rectum, they may be less sensitive in the long term.

Adrenergic Fibers↗

Evidence that cell bodies of non-cholinergic, excitatory neurones which supply the smooth muscle of the chicken rectum are located in the ganglia of Remak's nerve.

1. A pharmacological investigation of the distribution of non-cholinergic excitatory nerve cell bodies was performed on the chicken's isolated perfused rectum with attached Remak's nerve supply. 2. Electrical stimulation of Remak's nerve trunk produced a contraction and a discharge of action potentials in the nerve branches which supply the smooth muscle of the rectum. Both responses were virtually blocked by hexamethonium when applied via the caudal mesenteric artery. 3. The contractile effect following stimulation of the nerve trunk was inhibited more effectively by hexamethonium when application was restricted to the trunk rather than to the intestine. 4. The contractile effect of stimulating the nerve branches was unaffected by hexamethonium. 5. It is concluded that ganglionic transmission, which is mediated by nicotinic receptors, occurs in the ganglia of Remak's nerve but not in ganglia of the enteric plexuses. Therefore, cell bodies of the postganglionic neurones which are considered to be non-cholinergic are located in Remak's nerve ganglia.

Action Potentials↗

Membrane potential responses to ATP applied by pressure ejection in the longitudinal muscle of chicken rectum.

1. Changes in membrane potential in response to local application of ATP by pressure ejection from a micropipette were recorded intracellularly from smooth muscle cells of the longitudinal muscle strip of chicken rectum. 2. The local application of ATP produced a membrane depolarization. The depolarizing response increased to a plateau of 33 mV with prolongation of the duration of pressure pulses which determines the amount of ATP ejected. The latency and the time required to reach a peak depolarization were not related to the pulse duration, and the shortest latency was 50 ms. 3. When the application of ATP was repeated at a short interval, the second and subsequent depolarizing responses were suppressed, and their latency and time to reach a peak were also increased; the muscle cells became desensitized to ATP. Recovery from the desensitization occurred slowly over a period of 60 s. 4. Electrotonic potentials decreased in amplitude and time course during an ATP-induced depolarization, indicating a decrease in membrane resistance. 5. The ATP-induced depolarization was longer in the latency than an excitatory junction potential (e.j.p.) elicited by electrical field stimulation of the intramural nerves. The other variables such as amplitude, time to reach the peak and duration could not be matched with those of the e.j.p. at the same time. 6. The e.j.p. decreased in amplitude and duration during the ATP-induced depolarization, and its initial amplitude and duration were restored immediately after termination of the ATP-induced depolarization, as in the case of electrotonic potentials. The ej.ps were recorded in the same manner as the control from the muscle cell which was in a state of desensitization to ATP. 7. The present results provide an argument against the hypothesis that ATP mediates the ej.p. in the rectum of the chicken.

Adenosine Triphosphate↗

Membrane potential and current responses to neurotensin in the longitudinal muscle of the rectum of the fowl.

1. The effects of neurotensin (NT) on membrane potential and membrane current of the longitudinal smooth muscle of chicken rectum were investigated by intracellular recording and whole-cell voltage clamp. 2. NT (3 nM-1.2 microM), when applied via the bathing medium, produced a concentration-dependent membrane depolarization with an EC50 of 18 +/- 2 nM (n = 7) which was accompanied by an increase in the membrane conductance. The effect was biphasic: an initial, rapid depolarization reached a peak within 2-3 min and then declined to a lower but still elevated level which was sustained until washout. 3. Excitatory junction potentials (e.j.ps), which were non-adrenergic non-cholinergic (NANC) in nature, were decreased in amplitude and total duration in the presence of NT (0.6 microM). The depression of the e.j.p. was due mainly to the reduction of the membrane resistance. 4. When NT was applied locally by means of pressure ejection from a micropipette containing NT, some cells responded with a membrane depolarization and some failed to respond, whereas e.j.ps could invariably be elicited from all of them. 5. In single muscle cells enzymatically isolated from the muscle and dialyzed under voltage clamp at -50 mV with a CsCl-rich solution, NT (5 or 10 microM) produced an inward current. NT-induced inward currents were obtained with inclusion of 10 mM EGTA in the pipette solution and their reversal potential was around 0 mV. In cells dialyzed under voltage clamp at 0 mV with a KCl-rich solution, NT (5 microM) produced a brief outward current followed by abolition of spontaneous transient outward currents.6. The present results suggest that the membrane depolarization, which may arise from activation of non-selective cation channels, and release of calcium from internal stores produced by neurotensin are responsible for its contractile activity in the longitudinal smooth muscle of chicken rectum. Further, the depolarizing effect may provide support for the involvement of NT in the NANC transmission in this preparation.

Adenosine Triphosphate↗

Osmotic and ionic regulation during dehydration in a large bird, the emu (Dromaius novaehollandiae): an important role for the cloaca-rectum.

The emu, a large (40 kg) flightless bird, has low water requirements yet it has a limited ability to produce concentrated urine. To clarify the factors involved in excretion and water conservation by the emu the patterns of excretion during water restriction were examined. Additionally, kidney function was studied, as also was the role of the cloaca and rectum in the final modification of excreta. Following water restriction the osmolality of the excreta fluid increased to a maximum level at 6 d of 428 +/- 39(8) mosmol (mean +/- S.E.M. (n)), the urine to plasma ratio being 1.35 +/- 0.12(8). In normally hydrated birds almost all Na and Cl were excreted in the fluid fraction but a third of the K was associated with the solid fraction of the excreta. After water restriction for 9 d the pattern of excretion of K did not change but the majority of Na (79%) and Cl (73%) were excreted in the solid phase, possibly associated with urates. In ureteral urine most of the nitrogen was excreted as uric acid or urates; a large fraction, 36 +/- 4(4)%, was not identified. The glomerular filtration rate (G.F.R.) was 41.3 +/- 2.2(6) ml/kg.h. This value is low when compared with other birds and may be related to the large size of the emu. The G.F.R. decreased by 30% after 7 d water restriction. The cloaca-rectum appears to play a major role in the modification of excreta. In vivo perfusion studies showed transepithelial net transport rates of water and major electrolytes to be large. Transport of water from an isosmotic solution, 3.36 +/- 0.17 ml/kg.h, was approximately 10 times the maximum value reported for birds previously. The Na and Cl transport rates were also comparatively high.

Animals↗

Effects of morphine on electrical activity of the rectum in man.

1. The effects of morphine on the electrical activity of the human rectum were investigated. 2. In healthy volunteers, morphine (0.04-0.16 mg/kg, i.v.) induced spike activity that could become cyclical. 3. All the effects of morphine were antagonized by naloxone (0.03-0.2 mg/kg, i.v.), but not blocked by atropine (0.007-0.014 mg/kg, i.v.). 4. In patients with spinal cord injury, morphine was observed to have similar excitatory effects. Spinal cord transection was complete in all patients, so that participation of supraspinal nervous structures in these effects could be ruled out. The sacral parasympathetic nervous centres could not have been involved in two patients in whom the medullary cone was also destroyed. The thoracolumbar sympathetic nervous centres were not completely destroyed in any of the patients, however, so that the possibility that these centres may have been involved cannot be entirely ruled out. 5. Morphine failed to activate an aganglionic rectum in a patient with Hirschsprung's disease, indicating that it had no direct effect on smooth muscle cells. It is therefore probable that morphine may have an effect on the intrinsic innervation.

Action Potentials↗

[Positive rates of Neisseria gonorrhoeae and Chlamydia trachomatis on pharynx and rectum of patients with gonococcal or chlamydial genital infections].

In an attempt to know the applicability of non-cultural detection technique for N. gonorrhoeae and C. trachomatis on pharyngeal and rectal swabs, the swabs taken from N. gonorrhoeae- and C. trachomatis-free subjects were tested by Gonozyme, Chlamydiazyme, Ideia Chlamydia, Gen-Probe and Gen Probe Pace 2. As N. gonorrhoeae- and C. trachomatis-free subjects, the castrated males older than age 70, with known prostate cancer treated at least for 6 months with anti-androgens who were seronegative for C. trachomatis and had a history of Ofloxacin treatment in the last 3 months and whose pharyngeal and rectal swabs were negative for N. gonorrhoeae, were subjected for study. The false negative rates were for N. gonorrhoeae from the pharynx by Gonozyme 57.7%, by Gen-Probe 0%, by Gen-Probe Pace 2 0%, from rectum by Gonozyme 0%, by Gen-Probe 0% by Gen-Probe Pace 2 0%, for C. trachomatis from pharynx by Chlamydiazyme 93.8%, by Ideia Chlamydia 8.3%, by Gen-Probe 0%, by Gen-Probe Pace 2 0%, from rectum by Chlamydiazyme 94.4%, by Ideia Chlamydia 70.9%, by Gen-Probe 20.0% and by Gen-Probe Pace 2 0%. To investigate the incidence of pharyngeal and rectal infection by N. gonorrhoeae among the patients with gonococcal genital infection, as well as pharyngeal and rectal infection by C. trachomatis among the patients with chlamydial genital infection, pharyngeal and recal swabs obtained from the patients with genital infection by N. gonorrhoeae or C. trachomatis were tested by Gen-Probe Pace 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Induction of specific immunoglobulin A in the small intestine, colon-rectum, and vagina measured by a new method for collection of secretions from local mucosal surfaces.

In order study patterns of local antibody responses following mucosal immunization of mice via different routes, a method for collection of secretions directly from mucosal surfaces was developed. Mice were immunized on days 0, 10, 17, and 24 by administration of cholera toxin into the oral cavity, stomach, colon-rectum, or vagina. At sacrifice on day 32, absorbent wicks were placed in the oral cavity and, via an applicator tube, into the vagina and distal colon-rectum and along the entire small intestine after flushing of luminal contents. Protein was quantitatively extracted from wicks, and specific anti-cholera toxin immunoglobulin A (IgA) and IgG were measured by enzyme-linked immunosorbent assay. Concentrations of specific IgA in secretions at various mucosal sites were dramatically influenced by the route of immunization. Oral immunization effectively induced IgA in saliva, and the intragastric route was optimal for induction of IgA in the small intestine. High levels of specific IgA appeared on the colonic-rectal mucosal surface only after rectal delivery of antigen. Oral, gastric, and rectal immunizations also produced distant responses in the vagina. Following vaginal immunization, however, neither local nor distant IgA responses were detected. These results suggest that vaccines intended for protection of colonic-rectal and vaginal mucosal surfaces might best be administered by the rectal route.

Animals↗

Colonization in the rectum and uterine cervix with group B streptococci may induce specific antibody responses in cervical secretions of pregnant women.

We have studied the relationships between genital or rectal carriage of group B streptococci (GBS) with the levels of systemic and mucosal antibodies to GBS in 200 women at about week 17 of pregnancy. Secretions from the uterine cervix were collected with absorbent cylindrical wicks for quantification of antibody levels with whole cell enzyme-linked immunosorbent assay. GBS were cultured from the cervix (with or without concomitant rectal colonization) of 13.5%, from the rectum (with or without concomitant cervical colonization) of 12%, and from both culture sites of 8.5% of the women. Serotypes Ia, II, and III were predominant. Compared with culture-negative women, the group of women colonized rectally had markedly elevated levels of both immunoglobulin A (IgA) and IgG antibodies to GBS in cervical secretions and also had a moderate but significant elevation of IgA antibodies in sera. Women colonized only in the cervix had increases of specific IgA and IgG antibodies in cervical secretions, but their serum antibody levels were not elevated. In cervical secretions, the increase in antibody levels in the groups of colonized women was most pronounced for the IgG isotype, indicating a mucosal immune response involving IgG as well as IgA. A close correlation was found among the levels of antibodies to each of the three GBS serotypes tested. Evidence for such cross-reacting antibodies to different serotypes of GBS, as well as to group A streptococci, was also obtained from absorption experiments. Altogether, our results show that undiluted secretions for antibody determination can be easily collected from the uterine cervix with absorbent wicks and demonstrate that colonization of GBS in the rectum and the uterine cervix may induce a systemic as well as a pronounced local immune response in the female genital tract. The findings may have implications for the development of a mucosal vaccine against GBS disease.

Adolescent↗

Electrical potential difference, sodium absorption and potassium secretion by the human rectum during carbenoxolone therapy.

The transmucosal electrical potential difference (pd) and the sodium and potassium net fluxes were measured in the rectum of subjects taking carbenoxolone. There was a rise in transmucosal pd persisting throughout treatment in all subjects which was accompanied by an increase in sodium absorption and potassium secretion. Comparison of the pd changes produced by carbenoxolone with those due to the mineralocorticoid 9-alpha-fluorocortisol showed that carbenoxolone had about 1/1000th the potency on a weight basis and the two drugs appeared to be additive in their effects. Topical instillation of carbenoxolone into the rectum produced an elevation of pd which persisted for three days. Amiloride and bendrofluazide did not interfere with these actions of carbenoxolone but spironolactone abolished them. One patient who developed fluid retention and hypokalaemia had a rectal pd similar to that of the other patients who had no side effects.

Adult↗

Sensibility of the rectum to distension and the anorectal distension reflex in ulcerative colitis.

The maximum volume of air tolerated within a rectal balloon was less in colitic patients than in normal subjects (P less than 0.001). Smaller volumes were tolerated by patients with a spontaneously bleeding mucosa than by those with less severe inflammation (P less than 0.001). Severe urgency of defaecation with incontinence was experienced by about half those with spontaneous mucosal haemorrhage but was infrequent among other colitics. Those patients with inactive colitis and a reduced maximum tolerable volume tended to have a smaller rectal size than those who could tolerate a normal volume within the rectum. Reflex relaxation of the internal anal sphincter on distension of the rectum appeared normal in patients with colitis.

Adult↗

The histogenesis of carcinoid tumours of the rectum.

;Carcinoid' tumours of the rectum have been described which are classified on histological appearances into three main varieties: ;true' carcinoid or argentaffinoma, ;atypical' or non-argentaffin carcinoid, and ;composite carcinoid. The histogenesis of these tumours is discussed and it is suggested that non-argentaffin carcinoids of the rectum have an essentially similar histogenesis to certain tumours of the lung, pancreas, and gastrointestinal tract. The difference in growth, pattern, and staining reactions are a reflection of differing directions and levels of differentiation of the parent epithelium. The functional implications of this hypothesis are discussed.

Adenocarcinoma↗

Battle injuries of the rectum: options for the field surgeon.

Historically, battle wounds of the rectum have had high mortality and morbidity. This has improved greatly over several decades as a result of battle experience. This article highlights the value of civilian gunshot experience and its possible use in the military setting. The standard principles of rectal examination, followed by proctosigmoidoscopy after initial resuscitation, remain unchanged. Thereafter, the surgical decisions are made at laparotomy. Rectal injuries commonly have other injuries in association which must also be dealt with. In the stable patient rectal repair may be possible. Where repair is hazardous due to extensive injury (rectum or adjacent structures), the well-proven protective colostomy is used. A loop colostomy with or without distal closure is effective and is used to protect most injuries; possible exceptions being injuries dealt with early, in which there is minimal contamination and repair is easy. Presacral drainage can generally be reserved for severely destructive wounds or those in which repair has not been done. Rectal washout remains an option in patients with inspissated faeces. The basic military surgical principles remain valid, their extent and degree of implementation depending on the anatomical location of injury, degree of damage and any delay in presentation to surgery.

Colostomy↗

Responses of the isolated rectum of the rainbow lizard (Agama agama) to sympathomimetics.

The relaxant effects of isoprenaline, noradrenaline, and adrenaline on the isolated rectum of the rainbow lizard (Agama agama) were studied. Responses were measured as a reduction of carbachol-induced contractions for each sympathomimetic agent. Isoprenaline, adrenaline, noradrenaline produced a dose-dependent relaxation of this preparation and the order of potency was as given. The pD2 value of 8.15 +/- 1.88 obtained for isoprenaline was significantly different (p less than 0.05) from those for adrenaline (5.80 +/- 0.90) and noradrenaline (5.25 +/- 1.18). H35/25, propranolol, and practolol competitively antagonized the relaxant effects of isoprenaline on the isolated lizard rectum. The pA2 values for these beta-adrenoceptor antagonists did not differ significantly (at p less than 0.05). alpha-Adrenoceptor antagonists, phentolamine and phenoxybenzamine, failed to alter the relaxant responses of these sympathometics to any appreciable extent. These results are interpreted to suggest that the relaxant effect produced by these sympathomimetics are mediated predominantly by beta-adrenoceptors that are not significantly differentiated into subtypes. alpha-Adrenoceptors in this preparation contribute minimally to the observed inhibitory response following sympathomimetic stimulation.

Adrenergic alpha-Antagonists↗

The effect of prednisone and irradiation on the rectum in dogs.

In an attempt to diminish the severity of the acute and late effects of irradiation to the rectum of dogs, oral prednisone was administered to 10 dogs for 1 week prior to, during, and for 1 month following a 3-week fractionated course of 60Co exposures to the pelvis. A control group of 10 dogs received irradiation alone. The dogs were observed clinically, serial rectal biopsies were done during and following the acute reaction, and the rectum was studied following sacrifice. Observations suggest that prednisone has no beneficial effect on the acute inflammatory reaction, and increases the severity of the late tissue damage.

Animals↗

Computed tomography of the rectum.

CT is an important diagnostic procedure in patients with suspected or known disease of the rectum. Knowledge of proper technique for CT of the rectum, as well as an understanding of normal pelvic anatomy, is essential to its effective use. CT can demonstrate the extent of perirectal and pararectal abnormalities detected on barium enema. While routine preoperative staging of rectal cancer is not justified, CT can be used to solve specific problems. Perhaps the most important role of rectal CT is in evaluating postoperative rectosigmoid cancer patients in an attempt to detect early asymptomatic recurrences and, thereby, prolong patient survival.

Abscess↗

Rectum has abnormal ion transport but normal cAMP-binding proteins in cystic fibrosis.

The luminal membranes of involved tissues in cystic fibrosis (CF) are relatively impermeable to Cl and the regulation of Cl transport by adenosine 3',5'-cyclic monophosphate (cAMP)-mediated hormones is abnormal. We investigated the human rectum as a putative model for CF. We compared in vivo transrectal potential difference (PD) in CF and in normal subjects in response to sequential perfusions with various test solutions. The base-line PD was different in normal (-35.5 +/- 4.0 mV; lumen negative; mean +/- SE; n = 9) and CF subjects (-23.4 +/- 3.1 mV; n = 6; P less than 0.025) and was eliminated by amiloride (10(-4) M) perfusion in both groups by 3 min. However, in response to a Cl-free solution with amiloride, all six CF subjects exhibit less of a change in PD (PD, -2.2 +/- 1.2 mV vs. -11.7 +/- 1.5 mV in 6 controls; P less than 0.01). Furthermore, normal subjects (n = 7) respond to a 5 mM theophylline + amiloride perfusion with an increase in lumen-negative PD, whereas, CF subjects (n = 6) show no increase in lumen-negative PD. Rectal biopsy specimens from four normal and four CF subjects exhibit similar (2- to 3-fold) increases in theophylline-induced cAMP content and have similar cAMP-binding proteins (CF, n = 3; control, n = 3). We conclude that the rectum is an involved epithelium in CF in which the aberration may lie at a point beyond the binding of cAMP to its protein kinase.

Adult↗

Quantification of axial forces in rectum-anal canal of the cat.

A newly developed probe was used to measure in vivo axial forces in the rectum-anal canal of the anesthetized cat. Spontaneous contractions of the smooth muscle of the internal anal sphincter were recorded, as were neurally evoked contractions of striated muscle of the external anal sphincter. Bilateral electrical stimulation (1-10 V, 1-5 Hz, 0.05 ms duration) of motor axons in pudendal nerves elicited two responses. One was synchronous phasic contractions of skeletal muscle fibers of the external anal sphincter that were not abolished by atropine but were by gallamine trithiodide. They occurred at short latencies (1-2 ms) and were mediated through low-threshold (1-3 V, 0.05 ms duration) efferent axons in the pudendal nerves. Contraction times ranged from 45 to 60 ms, and contraction duration ranged from 100 to 160 ms. The second response was a progressive elevation in tone of the anal canal due to contractions either of the smooth muscle of the rectum and/or that of the internal anal sphincter. The elevation in smooth muscle tone concomitant with pudendal nerve stimulation may be due to reflex activation of cholinergic neural pathways, since the response was abolished by atropine.

Anal Canal↗