Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ligation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 973 records · Page 54Linked to original sources
PubMed2003

Unilateral spermatic vessel ligation in prepubertal rats decreases microvascular blood flow to ipsilateral testis postpubertally.

High ligation of spermatic vessels (HLSV) and low ligation of spermatic vessels (LLSV) have been described in the surgical treatment of high undescended testis. Testicular capillary blood flow utilizing laser Doppler flowmetry after these maneuvers has not been studied thus far; hence, this study was designed. Thirty male rats, aged 30 days, were randomized into three groups: group I, sham surgery; group II, unilateral HLSV ligation and division of main spermatic vessels high in the left retroperitoneal space; and group III, unilateral LLSV ligation and division of main spermatic vessels close to the left testis. Thirty days later, both testes were explored through scrotal incision and capillary blood flow was measured by laser Doppler flowmeter continuously and simultaneously from both testes. The right testis, the vessels of which were not disturbed in any group, served as the control. The mean decrease in the testicular blood flow between the right testis and left testis was 4.8, 92.9, and 74.2 PFU in groups I, II, and III respectively. There was a significant ( p<0.05) decrease in ipsilateral blood flow in group-II and group-III rats; however, upon comparing group II with group III, there was no significant difference between them. Both HLSV and LLSV in rats significantly decrease the capillary blood flow of ipsilateral testis. Although LLSV group had less reduction in capillary blood flow to the ipsilateral testis than HLSV group, the difference was not statistically significant.

Animals↗
PubMed2005

Prepubertal unilateral spermatic vessel ligation decreases haploid cell population of ipsilateral testis postpubertally in rats.

DNA flow cytometry is a sensitive and rapid technique to evaluate the germ cell maturation of testis. The haploid cell population of testis specifically denotes testicular maturation. High ligation of spermatic vessels (HLSV) and low ligation of spermatic vessels (LLSV) have been described in the surgical treatment of high undescended testis. Estimation of germ cell population of testis after these maneuvers has not been performed so far by DNA flow cytometry; hence this study was designed. Thirty male rats, aged 30 days, were randomized into three groups. Group I underwent sham surgery; group II underwent unilateral HLSV-ligation and division of main spermatic vessels, similar to the Fowler-Stephens technique; and group III underwent unilateral LLSV-ligation and division of main spermatic vessels close to the testis, similar to the Koff and Sethi technique. Thirty days later, the ipsilateral testes were harvested, and haploid, diploid, and tetraploid cells were counted by DNA flow cytometry. The mean (+/-SD) percentage of the haploid cell population was 68.7+/-4.8, 49.3+/-6.5, and 50.8+/-6.4 in groups I, II, and III, respectively. There was a significant (p<0.05) decrease in haploid cell population between groups I and II and between groups I and III. However, there was no significant difference between groups II and III. In conclusion, prepubertal HLSV as well as LLSV decreases the haploid cell population of ipsilateral testis in rats. LLSV has no advantage over HLSV.

Animals↗
PubMed2003

Comparison of early and 1-year follow-up results of conventional hemorrhoidectomy and hemorrhoid artery ligation: a randomized study.

BACKGROUND AND AIMS: Doppler-guided hemorrhoid artery ligation is a new approach for treating hemorrhoids. Early and 1-year follow-up results of the procedure are presented and compared with those of closed scissors hemorrhoidectomy in a prospective randomized study. PATIENTS AND METHODS: Sixty consecutively recruited patients were randomized into two groups: group A ( n=30) was treated with standardized closed scissors hemorrhoidectomy and group B ( n=30) with Doppler-guided hemorrhoid artery ligation. The follow-up period was 11.7+/-4.6 months. RESULTS: The average need for minor analgesics was 11.7+/-12.6 doses in group A and 2.9+/-7.7 in group B. Patients in group A spent 62.9+/-29.0 hours in hospital postoperatively and those in group B 19.8+/-41.8 hours. Return to normal daily activities took 24.9+/-24.5 days in group A and 3.0+/-5.5 days in group B. Neither the disappearance (26 vs. 25 patients) nor the recurrence of preoperative symptoms (5 vs. 6 patients) differed significantly between the two groups. CONCLUSION: Both procedures were effective in treating hemorrhoids. The 1-year results of Doppler-guided hemorrhoid artery ligation do not differ from those of closed scissors hemorrhoidectomy. Doppler-guided hemorrhoid artery ligation seems to be ideal for 1-day surgery, and it fulfills the requirements of minimally invasive surgery.

Anal Canal↗
PubMed1998

Rubber band ligation of hemorrhoids: relapse as a function of time.

Rubber band ligation is a well established treatment of internal second-degree hemorrhoids. Up to now, the long-term results (> 5 years) of this method have not been assessed. The aim of this study was to determine the long-term success rate of rubber band ligation in patients with a first episode of second-degree hemorrhoids not responding to medical treatment (local cream with laxative). A total of 92 patients who were treated between 1979 and 1997 for second-degree hemorrhoids responded to a questionnaire. The need for complementary conservative (sclerotherapy, cryotherapy or rubber band ligation) or surgical treatment was considered indicative of relapse. The collected data were analyzed according to the Kaplan-Meier method. The average follow-up time was 5.6 years. There were 21 patients who suffered a relapse. The probability of successful treatment was 0.77 (range: 0.67-0.88) after 5 years and 0.68 (range: 0.5-0.86) after 10.6 years. We conclude that rubber band ligation represent an efficient long-term treatment for second-degree hemorrhoids. Approximately two thirds of the patients are cured after 5 years and more than a half after 10 years.

Female↗
PubMed2006

Ligation of eustachian tube for intractable patulous eustachian tube: a preliminary report.

Pharyngeal orifice of the eustachian tube was ligated on ten patients, 15 ears with intractable patulous eustachian tube. While the eustachian tube orifice was observed by an endoscope inserted through the contralateral nostril, the orifice was ligated transnasally and/or transorally using instruments usually used in the endoscopic nasal surgery. Now 13-27 months after the surgery, the outcome was excellent (both symptoms and sonotubometry were normalized) in two ears, good (either symptoms or sonotubometry was improved) in seven ears, and unchanged in the remaining six ears. In one of the ears with an outcome of unchanged, the ligation was found to be spontaneously released soon after surgery, but the symptom was improved after the second operation 2.5 months after the first operation. Temporary otitis media with effusion was seen in one ear, mild inflammation around the ligated site also in one ear, but no other serious complication has been observed. Although further improvement in the surgical procedure and further discussion about its long-term outcome should be required, this procedure appeared to be one of the therapeutic options for intractable patulous eustachian tube.

Adult↗
PubMed1998

Sarcoplasmic reticulum Ca2+ loading in rabbits 8 and 15 weeks after coronary artery ligation.

Calcium uptake by cardiac sarcoplasmic reticulum (SR) is reported to be reduced in heart failure in the human and in a number of animal models. However, the majority of studies have examined end-stage heart failure in the human and few animal studies have taken account of the duration and severity of left ventricular dysfunction. In this study we have compared SR Ca2+ loading in a haemodynamically assessed, coronary artery ligation model of heart failure at 8 and 15 weeks after ligation. Trabeculae were isolated from the right ventricle and mounted for isometric tension measurement. They were treated with saponin to permeabilize the sarcolemma but retain SR function and bathed in a mock intracellular solution including adenosine triphosphate (ATP) and buffered Ca2+. Caffeine was used to release Ca2+ from the SR. The amplitude of the caffeine-induced contracture was used as a quantitative gauge of the Ca2+ content of the SR. Eight weeks after ligation, trabeculae demonstrated enhanced SR Ca2+ uptake as manifest by larger caffeine-induced contractures (e.g. 200 nM [Ca2+], 120 s loading - 38.2+/-9.2 versus 67.3+/-10.1% of maximum Ca2+-activated force, FCa, max, P=0.03). At 15 weeks, trabeculae from ligated hearts were not significantly different from controls with SR Ca2+ loading returning to control levels (e.g. 200 nM [Ca2+], 120 s loading - 47.3+/-9.6 versus 30.2+/-12.8% FCa, max, P=0.12). These data suggest that SR Ca2+ loading may increase in the early stages of heart failure and fall back to normal with an increasing duration of left ventricular dysfunction. Increased incidence of spontaneous Ca2+ release observed from the SR at 8 weeks and not at 15 weeks may represent an arrhythmogenic mechanism specific to the early phase of heart failure.

Animals↗
PubMed1999

A prospective randomized controlled trial of sclerotherapy vs ligation in the prophylactic treatment of high-risk esophageal varices.

BACKGROUND: Endoscopic ligation (EVL) and endoscopic sclerotherapy (EIS) are both effective in the treatment of bleeding esophageal varices, but the efficacy of the two techniques in the prophylaxis of first variceal bleeding has not been investigated. The aim of this study was to investigate the frequency of first variceal bleeding, the recurrence of varices, and survival after treatment with the two techniques, as compared to a nontreated control group. METHODS: A total of 157 patients with liver cirrhosis and advanced esophageal varices with no previous history of upper gastrointestinal bleeding were randomly assigned to either an EIS group (n = 55), an EVL group (n = 52), or a nontreated control group (n = 50). After the eradication of esophageal varices in the EIS and in EVL groups and in all control patients, the endoscopic examination was performed at 3-month intervals. RESULTS: There were no significant differences between EIS and EVL in the eradication rate of esophageal varices (85% in the EIS group versus 81% in the EVL group). The mean number of sessions required to obtain eradication was lower in the EVL group than in the EIS group (4.8 +/- 1.8 versus 6.2 +/- 2.0; p = 0.0003), but the recurrence of esophageal varices was higher in the EVL group (31% versus 11%; p = 0.01). Total mortality was significantly lower in the EIS patients than in the controls (20% versus 38%; p = 0.04). It was also lower, but not significantly, in the EVL patients than in the controls (23% versus 38%; p = 0.10). A significant decrease in variceal bleeding was observed both in sclerotherapy cases (20%) and controls (54%; p = 0.0005) and in ligation cases and controls (29%; p = 0.01). No significant difference in bleeding episodes was observed between the sclerotherapy and ligation cases (p = 0.29). No serious complications were observed either in the EIS or EVL groups. CONCLUSIONS: EIS and EVL are similarly effective in the prevention of first variceal bleeding. The choice between EIS and EVL depends on the skill of the endoscopic unit. For highly experienced surgeons facing no complications, sclerotherapy seems to be preferable; for all others, it is technically easier to perform ligation.

Adult↗
PubMed2004

Ductular cell proliferation in islet cell neogenesis induced by incomplete ligation of the pancreatic duct in dogs.

PURPOSE: It has been suggested that islet neogenesis can be induced by incomplete ligation of the pancreatic duct in small animals; however, there has been no report of neogenesis and the proliferation of islets occurring in larger animals. When this procedure was performed in the Vervet monkey, it produced a noticeable increase in duct proliferation, but islet neogenesis was not observed, although the number of monkeys examined was very small. We conducted this study to evaluate whether islet neogenesis and ductular proliferation could be induced in larger animals such as the dog, by partial obstruction of the pancreatic duct. METHODS: Incomplete ligation of the pancreatic duct was induced by tying the pancreas around the ventral side of the head with 2-0 silk and reducing the circumference by about 80% to cause partial obstruction. RESULTS: By 2 weeks after ligation, we saw hyperplasia of the epithelial cells, multilayering of cuboidal cells, and proliferation of ductular cells. The terminal ductules involved in the formation of immunohistochemically insulin-positive islets, and islets, formed adjacent to the alignment of the ductular cells. By 8 weeks after ligation we saw scattered islets, less than 50 micro m in diameter and less than 1 000 microm(2) in area. These cells were immunolabeled for both insulin and cytokeratin, and there was continuity between these insulin-positive cells and terminal ductular cells. Glucagon-positive cells and somatostatin-positive cells were also found adjacent to the alignment of ductular cells. CONCLUSIONS: These results suggest that islets may be differentiated from precursor cells in the pancreatic duct, and that stem cells exist even in adults.

Animals↗
PubMed2004

Closed subfascial ligation of incompetent perforating veins of the lower extremities.

The purpose of this study was to determine the effectiveness of minimally invasive surgical procedures for interrupting incompetent perforating veins of the lower limb. A closed subfascial ligation was performed in 20 patients who had incompetent perforating veins in 28 limbs as diagnosed by a clinical examination and duplex scanning. Two small transverse incisions measuring 5-10 mm in length were made on both sides of the incompetent perforating vein. Using an aneurysmal needle, a suture (polypropylene No. 1) was placed in the subfascial plane to encircle the incompetent perforating vein from all directions. Next, this suture was tied through two incisions to ligate this perforator. The mean follow-up period was 26 months. The ligation of the incompetent perforators was successful in 27 of 28 limbs and no wound complications were observed. A closed subfascial ligation of incompetent perforating veins of the lower limbs is thus considered to be easy to perform, not overly invasive, safe, and to also have very encouraging results.

Adult↗
PubMed2003

Short-term and long-term results of combined sclerotherapy and rubber band ligation of hemorrhoids and mucosal prolapse.

PURPOSE: Rubber band ligation is a common office procedure for symptomatic hemorrhoids. The aim of the study was to assess our short-term and long-term results of combined sclerotherapy and rubber band ligation in the management of hemorrhoids and incomplete mucosal prolapse. METHODS: Data on 6,739 patients who had previous combined sclerotherapy and rubber band ligation by the senior authors (GLN and PRD) were retrieved from the database dating between January 1976 and June 2000. These patients either had hemorrhoids or incomplete mucosal prolapse. Furthermore, questionnaires were sent to a random sample of 2,400 patients. Telephone interviews were performed for 600 of the nonrespondents. RESULTS: Of 6,739 patients (3,683 males; mean age, 46.7 years) in the database, 4,686 (70 percent) received the procedure once, and 2,053 (30 percent) received the procedure more than once. There were 5,689 patients (84 percent) who had their procedures performed consecutively within a planned period, and only 1,050 patients (16 percent) had repeat procedures after a period of more than 12 months from their last treatments. Thus, the recurrence rate was 16 percent. The overall complication rate was 3.1 percent, with minor bleeding being the major complaint. With regard to the questionnaire, 44 percent responded. The mean follow-up period was 6.5 (range, 1-11) years. There were patients who had residual symptoms of bleeding (19 percent), itch (21 percent), and lump (20 percent). However, 58 percent of patients who replied were asymptomatic. With satisfaction scores ranging from +3 to -3 (+3 indicating complete satisfaction and -3 indicating complete dissatisfaction), 90 percent scored >/=1, 9 percent scored 0 or less, and 1 percent did not specify a score. Hemorrhoidectomy was required in 7.7 percent of the responders. Of 600 phone interviews with the nonrespondents, 152 responded to the questionnaires. Although there was less satisfaction from the phone respondents, which may have accounted for the initial nonresponse, no statistical difference was detected in residual symptoms. CONCLUSIONS: Combined triple sclerotherapy and rubber band ligation is an effective treatment for early hemorrhoids and incomplete mucosal prolapse, with low rates of recurrence, complications, and hemorrhoidectomy, and it can be repeated easily.

Adolescent↗
PubMed2005

Doppler-guided hemorrhoidal artery ligation: an alternative to hemorrhoidectomy.

PURPOSE: Postoperative pain is the main adverse effect of formal hemorrhoidectomy. A new technique based on Doppler-guided ligation of the terminal branches of the superior hemorrhoidal artery was introduced in 1995 as an alternative to hemorrhoidectomy. The authors report a preliminary experience with this procedure. METHODS: The Doppler-guided hemorrhoidal artery ligation technique uses a special proctoscope bearing a Doppler transducer that allows identification and suture ligation of the hemorrhoidal arteries. Sixty-eight consecutive patients (mean age, 48 years; range, 21-74 years) with Grade 3 hemorrhoids were treated. RESULTS: Intraoperative discomfort was measured by a visual analog scale (1-10) and resulted in a mean score of 2.3 (range, 1.3-2.8). Only 38 percent of patients required postoperative analgesia. Patients were examined at 1 week, 1 month, and 3 months and every 6 months thereafter. The mean follow-up was 11 (range, 3-18) months. Bleeding resolved in 91 percent of patients, pain in 73 percent, and prolapse in 94 percent. Complications were recorded in five patients and included persistent pain for more than two days in two patients (3 percent), swelling and thrombosis of one of the hemorrhoids in two patients (3 percent), and a secondary hemorrhage in one patient (1.5 percent). CONCLUSION: Doppler-guided ligation of the hemorrhoidal artery is a safe and effective alternative to hemorrhoidectomy and is associated with minimal discomfort and low risk of complications.

Adult↗
PubMed2006

First 100 cases with Doppler-guided hemorrhoidal artery ligation.

PURPOSE: This study was designed to examine the benefits of a Doppler-guided hemorrhoidal artery ligation technique in terms of surgical outcome, functional recovery, and postoperative pain. METHODS: Using local, regional, or general anesthesia, 100 patients with symptomatic Grades II or III hemorrhoids underwent sonographic identification and suture ligation of six to eight terminal branches of the superior rectal artery above the dentate line. Visual Analog Scales were used for postoperative pain scoring. Surgical and functional outcomes were assessed at 6 weeks and 3, 6, and 12 months after surgery. RESULTS: There were 42 (42 percent) males and 58 (58 percent) females (mean age, 42 years; median duration of symptoms, 6.3 years). The mean operative time was 19 minutes. Local anal block combined with intravenous sedation (n = 93) or general or spinal (n = 7) anesthesia was used. Only five were hospitalized overnight. There was no urinary retention, bleeding, or mortality in the immediate postoperative course. The mean pain score decreased from 2.1 at two hours postoperative to 1.3 on the first postoperative day. All patients had a complete functional recovery by the third postoperative day. Ninety-four patients remained asymptomatic after a mean follow-up of six months: four patients required additional surgical excision, and two required rubber band ligations for persistent bleeding. On follow-up, there was no report of incontinence to gas or feces, fecal impaction, or persistent pain. CONCLUSIONS: Our experience indicates that Doppler-guided hemorrhoidal artery ligation is safe and effective and can be performed as an outpatient procedure with local or regional anesthesia and with minimal postoperative pain and early recovery.

Adult↗
PubMed2005

A randomized controlled trial of beta-blockers versus endoscopic band ligation for primary prophylaxis: a large sample size is required to show a difference in bleeding rates.

Primary prophylaxis with nonselective beta-blockers in high-risk subjects has been shown to be effective in reducing both esophageal variceal bleeding and mortality. Recently it has been suggested that band ligation may be a better option for primary prophylaxis. We compared nonselective beta-blockers with band ligation in patients with large varices (F2, F3) and elevated hepatic venous wedge pressure gradient (HVWPG, > or = 12 mm Hg). All patients were prospectively followed for variceal bleeding, mortality, and treatment-related complications. Based on previous published studies, we estimated that 90 patients in each arm would be required to show a difference in bleeding rate. The study was prematurely terminated when we realized that our estimated sample size was inadequate to show a difference based on the observed bleeding rate. At the time of termination, 31 patients (Child A, 11; B, 14; C, 6), with a mean HVWPG of 19 +/- 9.1 mm Hg, were randomized to either band ligation (group A; n = 16) or beta-blockers (group B; n = 15). Baseline demographics of both groups were similar and the mean follow-up period was 27.4 +/- 12.9 months. During the follow-up, two patients in group A and one patient in group B had bleeding. Nine patients (29%; group A, six; group B, three; P = ns) died due to non-bleeding-related causes and five (16%) patients (group A, three; group B, two) underwent liver transplantation. Treatment-related complication were minimal in both groups. Despite the selection of high-risk patients, the observed bleeding rate was much lower than anticipated. Based on our observed bleeding rates, 424 patients would be required in each arm to show a difference between band ligation and beta-blocker therapy.

Adrenergic beta-Antagonists↗
PubMed1990

The development of hydrops fetalis in the ovine fetus after lymphatic ligation or lymphatic excision.

Sixteen ovine fetuses underwent either ligation or excision of the left thoracic, left cervical, and left brachiocephalic lymphatic ducts. Our purpose was to test the hypothesis that interruption of lymphatic flow would lead to hydropic changes in the ovine fetus. Of the 11 animals in the group that underwent ligation, hydrops developed in 1. All five of the fetuses that underwent excision of these major lymphatic ducts were hydropic at the time of autopsy (3 to 7 days), with 62 to 502 ml of free fluid collected from the thoracic and abdominal cavities. The mean edema fluid total protein concentration in the hydropic fetuses was 2.6 gm/dl. This value was 71% to 94% of that found in the plasma, suggesting that the fetus is capable of producing new plasma proteins at a high rate. The observation that lymphatic excision led to hydropic changes in the ovine fetus, whereas ligation did not consistently produce hydrops, suggests that fetal lymph vessels may be capable of very rapid regrowth over short distances. Thus lymphatic excision, but not ligation, produces an animal model for the study of hydrops fetalis.

Analysis of Variance↗
PubMed1996

Incidence of vocal fold paralysis in infants undergoing ligation of patent ductus arteriosus.

BACKGROUND: Left-sided, iatrogenic vocal fold paralysis (IVFP) secondary to recurrent laryngeal nerve injury is a potential complication of ligation of patent ductus arteriosus (PDA). This study investigates specific risk factors associated with IVFP. METHODS: A retrospective chart review was performed for all infants 12 months of age or younger who underwent operative PDA closure at the University of Iowa from January 1, 1991, to January 1, 1994. RESULTS: Six cases of IVFP were diagnosed in 68 infants who underwent PDA ligation using clips (52.9%), suture ligatures (41.2%) or both (5.9%). Compared with infants without postoperative IVFP, infants with IVFP were smaller at birth (0.9 versus 2.3 kg; p < 0.001) and more premature (gestational age, 26.3 versus 33.8 weeks; p < 0.001), and were smaller (1.1 versus 3.4 kg; p < 0.001) and younger (31.9 versus 88.4 days; p < 0.001) at operation. Weight gain from birth to operation was significant only in infants without postoperative IVFP (p < 0.05). Although the overall incidence of IVFP in all infants undergoing PDA closure was 8.8%, five of the six cases (83.3%) of IVFP occurred in extremely low birth weight infants, ie, those weighing 1 kg or less at birth. Among the cohort of extremely low birth weight babies undergoing operation, the incidence of IVFP was 22.7%. Iatrogenic vocal fold paralysis was associated only with the use of surgical clips; however, because clips were used in 90.9% of the premature infants requiring PDA ligation, it was not possible to establish whether suture ligature is a safer technique. CONCLUSIONS: This study demonstrates that the single major risk factor for IVFP after ligation of PDA is birth weight less than 1 kg.

Birth Weight↗
PubMed1984

Regional cerebral blood flow and stroke index after left carotid artery ligation in the conscious gerbil.

We measured the regional cerebral blood flow in both hemispheres of Mongolian gerbils subjected to permanent left carotid artery ligation, using [3H]nicotine as the tracer. At 1, 3 and 6 h post-ligation, neurological signs were recorded and a stroke index score was tallied for each animal. In conscious control gerbils, mean cerebral blood flow on the left side was 1.10 +/- 0.08 (S.E.M.) ml X g-1 X min-1 at the cerebral cortex, 0.58 +/- 0.02 at the hippocampus and 0.69 +/- 0.04 at the diencephalon. Animals with a stroke index score exceeding 10 were considered symptomatic. We noted a close relationship between regional cerebral blood flow and the stroke index score. In symptomatic animals, regional cerebral blood flow in the ischemic hemisphere at 1, 3 and 6 h post-ligation was less than 0.21 ml X g-1 X min-1 at the cortex and diencephalon, and less than 0.09 ml X g-1 X min-1 at the hippocampus. We suggest that unilaterally ligated gerbils manifesting a stroke index score greater than 10 represent a good experimental model for the study of ischemia.

Animals↗
PubMed1980

Release of endogenous noradrenaline from ligated cat hypogastric nerve by veratridine.

The effect of veratridine on in vitro release of noradrenaline (NA) from ligated cat hypogastric nerve was investigated. After in vivo ligation for 24-48 h, large amounts of NA and dopamine-beta-hydroxylase (DBH) accumulated in the nerve segment immediately proximal to the ligature (P1). In vitro incubation of ligated nerves (segments P1 and P2) in oxygenated Krebs solution at 37 degrees C in the presence of veratridine caused a marked and dose-dependent release of endogenously accumulated NA into the incubation medium. The release continued to occur for a considerable time, even after washout of the drug. Veratridine-induced depletion of tissue NA was accounted for by its release, as NA, into the incubating medium. The secretory response to veratridine was readily blocked by tetrodotoxin (TTX). Veratridine-induced release was dependent on calcium and abolished by high magnesium. On the basis of the similarity between the NA secretory response to veratridine in this preparation and in adrenergically innervated organs, the results favour the view that the in vivo-ligated cat hypogastric nerve may serve as a useful model of adrenergic nerve terminals free of effector cells.

Animals↗
PubMed1993

Newly synthesized hepatocyte plasma membrane proteins are transported in transcytotic vesicles in the bile duct-ligated rat.

BACKGROUND: Newly synthesized apical membrane proteins in hepatocytes go first to the basolateral membrane, from which they are retrieved and delivered to the apical domain. The goal of the present study was to identify the vesicular carriers of these molecules. METHODS: The common bile duct of rats was ligated for 10-72 hours, and then various plasma membrane proteins were localized using immunofluorescence and quantitative immuno-electron microscopy of fixed liver tissue. RESULTS: By immunofluorescence, we found intracellular punctate staining near the bile canalicular membrane of polymeric immunoglobulin A (IgA) receptor and several apical membrane proteins, but not basolateral proteins. This compartment was membrane bounded and pleiomorphic by immunoelectron microscopy. Colocalization at the electron microscopic level showed that the apical protein, dipeptidyl peptidase IV, was in the same structures as aminopeptidase N, polymeric IgA receptor, or intravenously injected horseradish peroxidase. This intracellular immunolabeling decreased after cycloheximide treatment (t1/2 = 2-2.5 hours) or reversal of the ligation for 1 hour. In the latter case, bile canalicular labeling increased. Furthermore, polymeric IgA receptor was delivered to the bile canaliculi. CONCLUSIONS: Bile duct ligation leads to an intracellular accumulation of vesicles carrying polymeric IgA receptor, several apical membrane proteins, and a fluid phase marker. These vesicles continue to fuse with the apical membrane, even during ligation.

Animals↗