Strain Gauge Force Transducers Research Articles

Rectus femoris muscle flap donor-site morbidity

Donor-site morbidity in four patients after reconstruction with free neurovascular rectus femoris muscle was examined through a series of strength tests in which the leg with rectus femoris muscle harvested was compared with the contralateral leg with an intact rectus femoris muscle. The tests were conducted with three testing devices: (1) the 'Con-Trex Leg-press' in which the force and power of right and left leg extensions at 0.2 and 0.4 m/s in a knee angle from 50 to 90 degrees were tested separately; (2) the isometric power tester, which enabled the unilateral evaluation of the isometric leg extension at three knee angles: 50, 70 and 90 degrees ; and (3) at the 'SP-Force Platforms' in which the patients performed a counter-movement jump where the amplitude of the ground reaction force, the parameters maximum force, and the jump height were calculated in order to compare the right and left leg during a single dynamic movement. Our results showed that the patients (with one exception) demonstrated a balanced relationship between the donor leg and the intact contralateral leg. The patient that primarily demonstrated a large strength deficit was retested 3 months later and showed, after an extensive rehabilitation and training program, an impressive increase in strength. The authors concluded that there is no significant limitation in the strength of the donor leg after removal of the rectus femoris muscle and consequently no significant functional donor-site morbidity. We believe that for the realisation of such results that the intraoperative linking of the vastus lateralis muscle with the vastus medialis muscle, especially in their lower third, and an extensive postoperative rehabilitation and training program are essential.

Effects of Nitric Oxide Synthase Inhibitor on the Digestive System Measured by Simultaneous Monitoring of Gastric Motility, Gastric Emptying Activity and Postprandial Pancreaticobiliary Secretion in Dogs

Relationships between the NO synthase inhibitor and gastric and pancreaticobiliary functions measured simultaneously in the digestive state have been little studied. The aim of this study was to estimate the effect of NO synthase inhibitor on integrated digestive function in conscious dogs. A strain gauge force transducer was implanted on the gastric antrum of 6 mongrel dogs to measure gastric contractile activity and two duodenal cannulas were inserted into the proximal and distal sites to measure the gastric emptying rate and the pancreaticobiliary output into the duodenum using our novel method. Postprandial pancreatic and biliary secretion were presented as amylase and bile acid activity, respectively. Furthermore, a cervical cannula was placed into the superior vena cava as a route for the administration of NO synthase inhibitor, N omega-nitro-L-arginine (L-NNA), at a dose of 2.5 mg/kg-h. In a group given L-NNA, gastric contractile activity after ingestion was significantly enhanced, but the emptying rates of gastric solids and liquids were significantly suppressed in comparison with the control. The mean 0-1 h amylase integrated output was significantly (P < 0.05) decreased in comparison with the control, and the mean bile acid integration of 0-1 h output was also significantly (P < 0.01) decreased. A possible explanation for this observation is that smaller volumes of nutrient are delivered into the duodenum; however, it could also be that postprandial pancreaticobiliary secretion is inhibited by an alteration of blood flow or by a change in contractions of the sphincter of Oddi after the administration of L-NNA.

P0026 PP EFFECT OF GHRELIN ON THE GASTROINTESTINAL MOTILITY IN CONSCIOUS RATS

Introduction: Ghrelin, a novel growth-hormone-releasing peptide isolated from rat and human stomachs, has been reported to increase appetite in rats and humans. The clinical usefulness of this novel substance is currently under investigation. However, little is known about its direct effects on the alimentary. In the present study, we examined its effects on intestinal motility in conscious rats. Methods: Male Wistar rats weighing 300–400 g were fasted for more than 24 hours before experiments. After being anesthetized with pentobarbital, the abdominal wall was opened by mid-line laparotomy, and a miniature strain-gauge force transducer was sutured on the serosal site of intestinal wall 5 cm from the anal side of Treizüfs ligament. Five to 10 days after operation, and confirming the stability of the basal intestinal motility, various concentrations (1, 5, 10, 25, 50, and 100 ƒÊ g/kg, intravenous (IV) injection) of rat ghrelin or saline were given through the caudal vein after 4 minutes of phase 3 contractions. Intestinal motility was quantified by frequency and the mean amplitude of clusters, drug-cluster intervals, duration of clusters, and counting the number of phase 3 contractions. Results: When IV injections of ghrelin (over than 5ƒÊ g/kg) were given to animals, clusters appeared immediately and these patterns consisted of phase 3-like contractions. IV administration of ghrelin increased the frequency of clusters in a dose-dependent manner (Table 1). The mean amplitude of clusters was approximately 50% compared with that of previous natural phase 3 contractions. Drug-cluster intervals were shortened in a dose-dependent manner (Regression analysis: p=0.045). Each duration of clusters was about 2 min, and was shorter than that of natural phase 3 contractions 291 plus-minus 34 min. The number of phase 3contractions for one hour did not change before or after IV injections of ghrelin.Table 1: Induction of intestinal clusters by ghrelinConclusion: Exogenous ghrelin modulated small intestinal motility in conscious rats.

Regulation of gastric motility at simulated high altitude in conscious rats.

The aim of the present study was to examine the effects of acute exposure to hypobaric hypoxia on gastric and colonic motilities. Wistar rats, which were instrumented chronically with strain gauge force transducer to measure gastric and colonic motilities, were exposed acutely to hypobaric hypoxia [0.5 atmosphere absolute (ATA, 380 Torr)] over 1 h. In a separate group, the gastric branches of the vagal nerves were cut and underwent the same experimental protocol. Each contraction wave of the stomach and colon was analyzed into frequency and area under the curves, which were then averaged every 10 min. Acute exposure to 0.5 ATA resulted in significant (P < 0.05) decreases in frequency and area of gastric contraction wave by 0.5 +/- 0.1 cycles/min and 64.6 +/- 4.0%, respectively. Gastric vagotomy abolished completely the suppression in the area observed in the intact rats during the 0.5-ATA exposures. Colonic motility increased significantly only at the start and end of exposure to 0.5 ATA and sham exposure [1 ATA (760 Torr), time control] in both intact and vagotomized rats. These data suggest that the acute suppression of the area of the gastric contraction wave that occurred during 0.5-ATA exposure is likely to be mediated by the vagal nerve.

Real-time monitoring for detecting rejection using strain gauge force transducers in porcine small bowel transplantation

Purpose The clinical results of small bowel transplantation (SBT) have not been satisfactory mainly because of the immunological barrier. It is important to detect the presence of and to perform adequate treatment of rejection as early as possible to improve graft survival. Therefore, we have established a pig model to monitor graft motility as a means to detect rejection in real time. Methods Orthotropic SBT was performed in 25 pigs using FK-506 (0.05 to 0.1 mg/kg/d) immunosuppression. The interdigestive motor patterns were evaluated using strain gauge force transducers (SG). Seven pigs without SBT were treated as controls (C). Animals that displayed migrating motor complex (MMC) activity as evidenced by duration, amplitude, and interval in the graft were alive more than 10 days with adequate oral feeding: the functional graft (FG) group. In contrast the rejection (R) group did not show these activities on data recorded within 10 days before death due to rejection. Results The FG group showed MMC propagated throughout the graft with all parameters almost the same as the control group except for the duration. In contrast, all parameters in the group R were significantly lower than those in group FG, suggesting that group R motility was obviously impaired by rejection. Conclusions The SG method may afford real-time monitoring of transplanted bowel motility that could be useful to detect rejection after SBT.

A force measuring treadmill in clinical gait analysis

This preliminary study presents the development and testing of an instrumented treadmill device measuring the ground reaction forces (GRFs) and the feasibility of using this force measuring treadmill (FMT) in clinical gait analysis. A commercially available treadmill was modified and fitted out with three-dimensional strain-gauge force transducers. Tests of linearity, centre of pressure position (CoP), cross talk, natural frequency, background noises, and belt speed were undertaken in order to assess the performance of the FMT. In addition, the GRFs and segmental kinematics were recorded while healthy subjects and patients walked on the FMT, in order to compute the net ankle joint moments and the body centre of mass (CMb) kinematics and mechanics. The preliminary results of technical tests were satisfactory with an error less than 10% and dynamic tests in healthy subjects corresponded to the literature. The results of patients were clearly disturbed, demonstrating the ability of the FMT to discriminate pathological gaits from normal ones. We concluded that the GRFs measurements obtained from the FMT seem valid and the clinical assessment of net joint moments and CMb kinematics and mechanics seem feasible. The FMT could be useful device for clinical research and routine gait analysis since it allows gaining some extra room and quickly collecting the GRFs during a large number of successive gait cycles and over a wide range of steady-state gait speeds. However, more work is needed in this area in order to confirm the present results, collect reference data and validate the methodology across pathologies.

Efficacy of real-time monitoring to determine motility in porcine small intestinal transplantation.

Orthotropic small intestinal transplantation (SIT) was performed in outbred 20 pigs. The interdigestive motor patterns were evaluated using strain gage (SG) force transducers. Seven pigs without SIT were treated as control (C) group. Based on the obtained data, the group, which could be detected the migrating motor complex (MMC) in the graft and alive with adequate oral feeding, was regarded as functional graft (FG) group, whereas the group which had available data recorded within 10 days before the death due to rejection was regarded as rejection (R) group. The MMC was analyzed using following parameters: duration; amplitude; and interval. In group FG, all parameters were almost same as group C, thus suggesting that the allograft in group FG had a normal motor function. In contrast, all parameters in group R were significantly lower than those in group FG, suggesting that the motility in group R was impaired. The SG method could monitor the real-time motility and was efficient for detecting the rejection of SIT.

Glucose acts in the CNS to regulate gastric motility during hypoglycemia.

Our purposes were to 1) develop an animal model where intravenously (iv) administered d-glucose consistently inhibited antral motility, and 2) use this model to assess whether iv glucose acts to inhibit motility from a peripheral or a central nervous system site and to elucidate the factor(s) that determine(s) whether stomach motor function is sensitive to changes in blood glucose. Rats were anesthetized with alpha-chloralose-urethane, and antral motility was measured by a strain-gauge force transducer sutured to the antrum. In some cases, antral motility and gastric tone were measured by monitoring intragastric balloon pressure. Increases in blood glucose were produced by continuous iv infusion of 25% d-glucose at 2 ml/h. Inhibition of antral motility and gastric tone was observed when gastric contractions were induced by hypoglycemia (subcutaneously administered insulin, 2.5 IU/animal). In contrast, no inhibition of gastric motor function was observed when glucose infusion was tested on gastric contractions that were 1) spontaneously occurring, 2) evoked by iv administered bethanechol in vagotomized animals, and 3) evoked by the TRH analog RX77368, microinjected into the dorsal motor nucleus of the vagus. Using the model of insulin-induced hypoglycemia to increase gastric motor activity, we found that neither sectioning the hepatic branch of the vagus (n = 5), nor treating animals with capsaicin to destroy sensory vagal afferent nerves (n = 5) affected the ability of iv d-glucose to inhibit gastric motor function. Our results indicate that an important factor determining whether stomach motor function will be sensitive to changes in blood glucose is the method used to stimulate gastric contractions, and that the primary site of the inhibitory action of iv glucose on gastric motility is the central nervous system rather than the periphery.

Erythromycin induces pyloric relaxation accompanied by a contraction of the gastric body after pylorus-preserving gastrectomy

Background. Pylorus-preserving gastrectomy (PPG) is a function-preserving surgery; however, long-term retention of food in the residual stomach is a frequent complication during the early postoperative period. We reported that gastric stasis after PPG was attributable to the delayed recovery of gastric phase III, in which pyloric relaxation accompanied a contraction of the gastric body. The objective of the present study is to determine whether erythromycin can induce phase III with pyloric relaxation after PPG. Methods. We studied gastrointestinal motility in dogs after PPG by using strain gauge force transducer. After randomized administration of either erythromycin or saline, interdigestive gastropyloroduodenal motility was recorded. Results. Erythromycin induced phase III with pyloric relaxation in the early postoperative period. Pyloric relaxation accompanied a contraction of the gastric body. Compared with the saline group (body: 87.2 ± 16.7 mmHg × min, antrum: 69.7 ± 13.7 mmHg × min, pylorus: 91.7 ± 22.1 mmHg × min), the erythromycin group showed significantly increased gastropyloric motility indexes (body: 506.2 ± 33.5 mmHg × min, antrum: 430.9 ± 53.7 mmHg × min, pylorus: 589.5 ± 59.5 mmHg × min). Conclusions. Erythromycin can induce phase III, in which pyloric relaxation accompanied a contraction of the gastric body in the early postoperative period after PPG. Erythromycin might be used as a prokinetic agent for the treatment of early gastric stasis after PPG. (Surgery 2003;133:647-55.)

A 5-HT4 agonist mosapride enhances rectorectal and rectoanal reflexes in guinea pigs.

The rectal distension-evoked reflex rectal (R-R) contractions and internal anal sphincter (R-IAS) relaxations in guinea pigs were generated through the extrinsic sacral excitatory nerve pathway (pelvic nerves) and the intrinsic cholinergic excitatory and nitrergic inhibitory nerve pathways. The aim of the present study was to evaluate whether a prokinetic benzamide, mosapride, enhances the R-R and R-IAS reflexes mediated via 5-HT4 receptors in the guinea pig. The mechanical activities of the R and IAS were recorded with a balloon connected to a pressure transducer and a strain gauge force transducer in the anesthetized guinea pig with intact spinal-intestinal pathways. Gradual and sustained rectal distension evoked R-R contractions and synchronous R-IAS relaxations. Mosapride (0.1-1.0 mg/kg i.v.) dose-dependently enhanced both R-R and R-IAS reflex responses. Reflex indexes for R-R and R-IAS maximally increased from 1.0 (control) to 1.92 and 1.88, respectively. A specific 5-HT4 receptor antagonist, GR 113808 (1.0 mg/kg i.v.), antagonized the enhancement of the R-R and R-IAS reflexes induced by mosapride 1.0 mg/kg i.v. The present results indicate that mosapride enhanced the R-R and R-IAS reflexes mediated through 5-HT4 receptors.

Stimulatory action of itopride hydrochloride on colonic motor activity in vitro and in vivo.

We investigated the effects of itopride hydrochloride (itopride, N-[4-[2-(dimethylamino)ethoxy]benzyl]-3,4-dimethoxybenzamide hydrochloride), a gastroprokinetic agent, on the colonic motor activity in vitro and in vivo, in comparison with benzamides, cisapride hydrate (cisapride), and mosapride citrate (mosapride). Itopride stimulated both peristaltic and segmental motility induced by applying intraluminal pressure to the isolated guinea pig colon. Although cisapride and mosapride enhanced the segmental motility, they markedly reduced the peristaltic motility. In conscious dogs with implanted strain gauge force transducers, itopride stimulated contractile activity in the gastrointestinal tract from the stomach to the colon. Cisapride stimulated contractile activity in the gastric antrum, ileum, and ascending colon. Mosapride stimulated contractile activity only in the gastric antrum and ileum. In guinea pigs and rats, itopride accelerated colonic luminal transit. On the other hand, cisapride and mosapride failed to enhance colonic transit. These results demonstrate that itopride has a stimulatory action on colonic peristalsis, propelling colonic luminal contents, different from that of cisapride and mosapride. Therefore, itopride may be a useful drug for the treatment of functional bowel disorders such as functional constipation.

Neural control of the internal anal sphincter motility.

Control mechanism of smooth muscle movement of the internal anal sphincter (IAS) by enteric and extrinsic neuvous systems in the dog was investigated. Responses of IAS muscle strips to electrical field stimulation (EFS) and neurotransmitter agents were recorded in vitro. The contraction response to norepinephrine or to EFS was inhibited by phentolamine. The relaxation induced by EFS was not affected by phentolamine, propranolol or atropine. The mechanical activity of smooth muscle in colon and anorectum during spontaneous defecation was recorded using strain gauge force transducers. The colon and anorectum showed the characteristic motility pattern during defecation: 1) The giant migrating contraction of the colon propagated to the rectum, 2) The relaxation of the rectum prior to the contraction, and 3) The IAS muscles continued to relax while the giant contractions of the colon were migrating to the rectum. Sacral nerves were stimulated electrically and the responses of smooth muscles in the rectum and IAS were recorded. The sacral nerve stimulation induced a relaxation followed by contraction of smooth muscle in the rectum and the relaxation in IAS. The mechanical responses of smooth muscle in the IAS were modulated by alpha-adrenergic excitatory and non-adrenergic, non-cholinergic inhibitory nerves. During defecation, the relaxation of IAS smooth muscle was associated with a characteristic motility pattern of the colon and anorectum. The enteric nervous systems may be organizing the motility of these muscles by way of the motor neurones under the control the extrinsic nervous systems.

Intraileal capsaicin inhibits gastrointestinal contractions via a neural reflex in conscious dogs

Background & Aims: The aim of the present study was to determine the effect of intraileal administration of capsaicin on gastrointestinal motility. Methods: Mongrel dogs equipped with strain gauge force transducers on the stomach, small intestine, and colon were used. We studied the effects of intraileal capsaicin on gastrointestinal contractions with or without pharmacologic antagonists. The effects of capsaicin administration into the lumen of innervated and extrinsically denervated ileal Thiry loops were also studied. Results: Intraileal capsaicin dose dependently inhibited postprandial contractions at all sites and interdigestive contractions in the upper gastrointestinal tract. Intraileal capsaicin-induced inhibition of gastrointestinal contractions was partially reversed by a nitric oxide (NO) synthase inhibitor, a 5 hydroxytryptamine-3 receptor antagonist (5-HT3), and an opiate antagonist. Administration of capsaicin into the innervated ileal Thiry loop had inhibitory effects on gastrointestinal contractions, but gastrointesinal motor activity was not affected by capsaicin administered into the extrinsically denervated Thiry loop. Conclusions: Stimulation of ileal afferent fibers by capsaicin inhibits gastrointestinal contractions via an extrinsic neural reflex.GASTROENTEROLOGY 2002;123:1904:1911

Changes in gastrointestinal motility after subtotal colectomy in dogs.

This study was conducted to examine recovery from diarrhea after subtotal colectomy by observing changes in gastrointestinal motility, neuropeptides, and autonomic nerves in the enteric nervous system in dogs. The moisture volume of intestinal matter recovered from the ileal side of the anastomosis was defined as the diarrhea index. Gastrointestinal motility was measured using strain gauge force transducers (SG) for 24 weeks after subtotal colectomy. Immunohistochemical changes in neuropeptides in the residual intestine, acetylcholinesterase activation of cholinergic fibers, and fluorohistochemical changes of adrenergic fibers in the myenteric plexuses were evaluated. The digestive tract transit time returned to normal in the early postoperative period, but decreased moisture volume was seen in the intestinal matter after 8 postoperative weeks. Migrating contraction waves propagating beyond the site of anastomosis, signaling recovery of intestinal motility, were noted after 8 postoperative weeks, corresponding to reconstruction of cholinergic fibers in the anastomotic section. Transient activation of vasoactive intestinal polypeptide was seen in the residual intestine, but this had normalized by the eighth postoperative week. Lengthened villi in the residual intestine were also seen after 8 postoperative weeks. The decreased moisture volume in the intestinal matter is due to the improvements we observed in the eighth postoperative week.

Preventive effects of parathyroid hormone-related peptide on stress-induced gastric hypercontraction in the rat.

Parathyroid hormone-related peptide (PTHrP) appears to be a potent smooth muscle relaxant, but there has been no study of its effects on gastric motility in vivo. The purposes of this study were to evaluate the effects of external PTHrP on stress-induced gastric motility in vivo and on the expression of PTHrP and PTH/PTHrP receptors in the rat stomach. Stress-induced hypercontraction was evoked by restraint water immersion (RWI). Gastric motility was evaluated with a strain gauge force transducer, and the effects of external PTHrP-(1-34) (10 micro i.p.) on gastric motility were examined. Expressions of PTHrP and PTH/PTHrP receptor mRNA were evaluated by RNase protection assay. External PTHrP significantly suppressed abnormal contraction and mucosal lesions upon RWI stress. Upon RWI stress, the expression of PTHrP mRNA decreased, but that of PTH/PTHrP receptor mRNA was enhanced reciprocally. The PTH/PTHrP receptor was localized in smooth muscle cells of the muscle layers immunohistochemically. These findings suggest that smooth muscle contractile activity is modified by the autocrine/paracrine mechanism of PTHrP in the rat stomach and that the external PTHrP prevents stress-induced hypercontraction and mucosal lesions.

Intraduodenal capsaicin inhibits gastric migrating motor complex via an extrinsic neural reflex in conscious dogs.

The aim was to study the effect of intraduodenal capsaicin on interdigestive gastric contractions. Mongrel dogs were equipped with strain-gauge force transducers to measure gastroduodenal motility. The effects of intraduodenal capsaicin with or without pharmacological antagonists on spontaneous and motilin-induced interdigestive gastric contractions and on plasma motilin were studied in dogs with intact stomachs. The effect of intraduodenal capsaicin on gastric contractions was also studied in vagally denervated gastric (Heidenhain) pouch and vagally innervated antral pouch. Intraduodenal capsaicin inhibited spontaneous and motilin-induced gastric contractions. The spontaneous peak in plasma motilin was inhibited by intraduodenal capsaicin. The effect of intraduodenal capsaicin on motilin-induced gastric contractions was not affected by blockade of nitric oxide synthase, or by beta-adrenoceptor antagonist. Administration of alpha-adrenergic blocker inhibited basal interdigestive gastric motility. Intraduodenal capsaicin had no effect on contractions in the Heidenhain pouch but inhibited those in vagally innervated antral pouch. Duodenal afferent fibres stimulated by capsaicin inhibit gastric contractions via a nitric oxide-independent extrinsic neural reflex.

Effects of extrinsic autonomic denervation and myenteric plexus transection on colonic motility in conscious dogs

Background. The role of extrinsic autonomic nerves in regulation of colonic contractile activity is not well understood. Methods. Twelve dogs had 6 strain gauge force transducers implanted in the colon and were divided into 3 experimental groups: (1) a control group, (2) an extrinsic denervation group (denervation group), and (3) an extrinsic denervation with proximal intrinsic myenteric plexus transection group (denervation + transection group). After recovery, colonic contractile activity during fasting and effects of feeding on gastrocolonic response were recorded. Results. Colonic contractile activity occurred not only in the denervation group but also in the denervation + transection group. Both mean duration and propagation time of the colonic contractile activity were shorter in the denervation + transection group than in the control group. In the denervation group, propagation time was shorter than in the controls but the other parameters were not different. Feeding failed to immediately induce the gastrocolonic response in both experimental groups. Conclusions. We conclude that extrinsic nerves are not required for the appearance of colonic contractile activity. However, colonic contractile activity and its propagation are modulated by extrinsic innervation or proximal intrinsic neural continuity. Gastrocolonic response may be predominantly under extrinsic neural control. (Surgery 2002;132:471-9.)

Integrative control of rectoanal reflex in guinea pigs through lumbar colonic nerves.

The aim of the present study was to analyze the neuromodulation of rectoanal reflex activity by lumbar sympathetic nerves in guinea pigs. The mechanical activities of the rectum were recorded with a balloon connected to a pressure transducer, and those of the internal anal sphincter (IAS) were recorded with a custom-made strain gauge force transducer. Gradual and sustained rectal distension evoked the rectoanal reflex, causing cholinergic contractions of the rectum and synchronous nitrergic relaxations of the IAS. Section of the lumbar colonic nerves enhanced both rectal contractions and IAS relaxations. Section of the 13th thoracic cord abolished both rectal contractions and IAS relaxations, but section of the lumbar colonic nerves restored them. Lumbar sympathectomy and pithing sacral cords greatly diminished these rectal contractions and IAS relaxations, but the intrinsic reflex component remained. NG-nitro-L-arginine methyl ester enhanced the intrinsic reflex-mediated contraction of the rectum and abolished reflex-mediated relaxation of the IAS and converted into cholinergic contractions. The present results indicate that the extrinsic lumbar inhibitory outflow causes marked inhibition of the rectoanal reflex via the lumbar colonic nerves.

Motility of the gastrointestinal tract and gallbladder during long-term total parenteral nutrition in dogs.

The motility of the gastrointestinal tract during total parenteral nutrition (TPN) remains poorly understood. The objective of this study was to determine the motility pattern not only in the gastrointestinal tract but also in the gallbladders of dogs maintained by TPN. Central venous catheters were inserted through the external jugular vein of 5 dogs and 6 strain gauge force transducers were sewn to the stomach, small intestine, and gallbladder. Two weeks later, oral food was discontinued and motility was recorded for 24 hours after the first migrating motor complex (MMC) was confirmed in the stomach as pre-TPN. TPN was started and continued for 4 weeks, and patterns of motor activity during TPN were recorded for 24 hours at the end of each week. The durations of MMC in the stomach, duodenum, and gallbladder in pre-TPN were 118 +/- 3 minutes, 118 +/- 2 minutes, and 118 +/- 2 minutes, respectively, but in the first week of TPN they were 432 +/- 56 minutes, 431 +/- 56 minutes, and 386 +/- 29 minutes, respectively. TPN times were significantly longer than those of pre-TPN (corrected p < .005). The durations of MMC in jejunoileum did not alter between pre-TPN and TPN. The occurrences of phase III in the stomach, duodenum, and gallbladder in pre-TPN were 12/d, but during TPN they were reduced significantly (corrected p < .005). TPN did not affect the motility of the jejunoileum but did inhibit the motor activities of the stomach, duodenum, and gallbladder. The inhibition of gallbladder contraction observed during TPN may be one of the factors inducing gallbladder disease.

Pyloric motility after pylorus-preserving gastrectomy with or without the pyloric branch of the vagus nerve.

An attempt was made to examine gastropyloric motility after pylorus-preserving gastrectomy (PPG) and to determine the influence of the pyloric branch of the vagus nerve in the dog. Fifteen dogs were divided into three groups of five. PPG with preservation (PPPG) and resection of the pyloric branch of the vagus (RPPG) were performed, and controls were prepared. Interdigestive and digestive gastropyloroduodenal motility was recorded after a 2-week recovery period using strain-gauge force transducers (SG). Radiopaque markers (ROMs) were used to assess gastric emptying. No significant differences were found between PPPG and RPPG in terms of gastropyloroduodenal motility during either the interdigestive or the postprandial state. During phase III of the interdigestive state, pyloric relaxation correlated with contraction of the gastric body after both PPPG and RPPG. During the first month it was accompanied by tonic and phasic pyloric contractions after feeding and delayed gastric emptying in two groups. By the end of the first month these pyloric contractions had diminished, and the rate of gastric emptying was similar to that of the controls. We concluded that it is not necessary to preserve the pyloric branch of the vagus for gastropyloroduodenal motility after PPG. Gastric stasis during the early postoperative period is due to tonic and phasic contractions of the pylorus.