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PubMed1978

Modification of the size of developing infarcts in the ligated dog heart by betahistine-HCL.

The effectiveness of beta-histine-HCL in modifying the size of developing myocardial infarcts was tested in the surgically ligated dog. Branches of the left coronary artery were ligated and a 6-hour continuous intravenous infusion of 0.24 mg/kg/min of beta-histine was administered from 0 to 120 min after ligation. The effect of this treatment was evaluated histologically in studies on acute ischemia by the use of the hematoxylin-basic fuchsin-picric acid stain for early myocardial ischemia. The treatment was also evaluated grossly in a study on chronic ischemia where the dogs were permitted to survive for 30 days before sacrifice. In these experiments the size of infarcts found in the beta-histine-treated animals was compared with those found in the saline controls. Both studies showed that the control ligations produced a large uniform area of ischemia or infarction that was greatly reduced or prevented by immediate treatment with beta-histine. Also, beta-histine was capable of significantly reducing the size of developing infarcts for up to 120 min after ligation.

Animals↗
PubMed2001

Mouse carotid artery ligation induces platelet-leukocyte-dependent luminal fibrin, required for neointima development.

The relationship between platelet and leukocyte activation, coagulation, and neointima development was investigated in noninjured murine blood vessels subjected to blood stasis. The left common carotid artery of C57BL/6J mice was ligated proximal to the bifurcation. Tissue-factor expression in luminal leukocytes progressively increased over 2 weeks. On day 3 after ligation, in addition to infiltrated granulocytes, platelet microthrombi and platelet-covered leukocytes as well as tissue-factor-positive fibrin deposits lined the endothelium. Maximal neointima formation in carotid artery cross sections of control mice equaled 28+/-3.7% (n=11) and 42+/-5.1% (n=8) of the internal elastic lamina cross-sectional area 1 and 2 weeks after ligation. In FVIII(-/-) mice, stenosis was significantly lower 1 (11+/-3.6%, n=8) and 2 (21+/-4.7%, n=7) weeks after ligation (both P:<0.01 versus background-matched controls). In u-PA(-/-) mice, luminal stenosis was significantly higher 1 (38+/-7.0%, n=7) and 2 (77+/-5.6%, n=6) weeks after ligation (P:<0.05 and P:<0.01, respectively, versus matched controls). In alpha(2)-AP(-/-) mice, stenosis was lower at 1 week (14+/-2.6%, n=7, P:<0.01) but not at 2 weeks. Responses in tissue-type plasminogen activator or plasminogen activator inhibitor-1 gene-deficient mice equaled that in controls. Reducing plasma fibrinogen levels in controls with ancrod or inducing partial thrombocytopenia with busulfan resulted in significantly less neointima, but inflammation was inhibited only in busulfan-treated mice. We conclude that stasis induces platelet activation, leading to microthrombosis and platelet-leukocyte conjugate formation, triggering inflammation and tissue-factor accumulation on the carotid artery endothelium. Delayed coagulation then results in formation of a fibrin matrix, which is used by smooth muscle cells to migrate into the lumen.

Afibrinogenemia↗
PubMed1999

Osteogenic protein-1 protects against cerebral infarction induced by MCA ligation in adult rats.

BACKGROUND AND PURPOSE: Osteogenic protein-1 (OP1) not only possesses trophic activity on bone tissue but also influences neuronal survival and differentiation in vitro. Specific receptors for OP1 are present in brain and spinal cord and can be upregulated during cerebral contusion. OP1 is a member of the transforming growth factor-beta superfamily, several of whose members possess neuroprotective activity. In this study, the neuroprotective effect of OP1 in cerebral ischemia was evaluated in adult animals. METHODS: Adult male Sprague-Dawley rats were anesthetized with chloral hydrate. OP1 or vehicle was administered intracortically or intracerebroventricularly to the rats. Thirty minutes, 24 hours, or 72 hours after OP1 injection, the right middle cerebral artery (MCA) was ligated for 90 minutes. Twenty-four hours after reperfusion, animals were tested for motor behavior. The animals were subsequently anesthetized with urethane and perfused intracardially with saline. Brain tissue was removed, sliced, and incubated with 2% triphenyltetrazolium chloride to localize the area of infarction. RESULTS: Only animals pretreated with OP1 24 hours before MCA ligation showed a reduction in motor impairment. OP1, given 30 minutes or 72 hours before MCA ligation, did not reduce cortical infarction. In contrast, pretreatment with OP1 24 hours before MCA ligation significantly attenuated the volume of infarction in the cortex, in agreement with the behavioral findings. CONCLUSIONS: Intracerebral administration of OP1 24 hours before MCA ligation reduces ischemia-induced injury in the cerebral cortex.

Animals↗
PubMed1994

Hemodynamic changes in the head and neck after ligation of the unilateral carotid arteries: a study using color Doppler imaging.

For evaluation of the hemodynamics of the collateral circulation to the ligated external carotid artery (ECA) region, we measured the blood flow direction and volume in branches of the ECA in patients with unilateral carotid artery ligation before and during digital suppression of the common carotid artery (CCA) on the ligated and nonligated sides with color Doppler imaging and angiography. The main collateral pathway to the ligated ECA region was the ipsilateral occipital artery through Richter's anastomosis from the vertebral artery in the case of unilateral ECA ligation, and was the contralateral carotid artery in the case of unilateral CCA, ECA, and internal carotid artery resection. The superior and inferior labial arteries were important as the collateral pathway from the contralateral ECA.

Blood Flow Velocity↗
PubMedDate not supplied

Experimental carcinogenesis in duct-artery ligated rat submandibular gland.

In an attempt to shorten tumor induction time and alter tumor anaplasticity, ductal metaplasia was induced in the submandibular gland of 30 rats by ligation of the duct and artery followed by the implanation of 4-mg pellets of pure DMBA. Control groups consisted of 19-ligated and 15-DMBA implanted rats. The ligate controls showed degeneration and atrophy of the affected gland and replacement of glandular tissue by scar tissue. The DMBA controls followed the expected pattern, with all rats eventually developing well-differentiated squamous cell carcinoma. The CMBA-ligated rats showed a combination of the two processes, each acting separately from the other. There was no difference either in induction time or tumor anaplasticity between the DMBA control rats and the DMBA-ligated rats. It seems that only factors relating to a change in the immunologic response of the host affect the latent period of tumor induction time in submandibular gland carcinogenesis.

Animals↗
PubMed1999

Morphological and functional characteristics of acinar atrophy and recovery in the duct-ligated parotid gland of the rat.

Although acinar atrophy occurs frequently in salivary diseases, the relationship between structural changes and functional decrements is not well-established, and the potential for recovery of histological and functional integrity has not been wholly quantified. We aimed, therefore, to develop further our understanding of pathological acinar atrophy. Stensen's duct was ligated for periods up to six weeks and, in separate experiments, was de-ligated after two weeks and allowed to recover for up to two weeks. Qualitative and quantitative histological analyses were carried out. Additionally, the ability of enzymatically dispersed cells from ligated and de-ligated glands to respond to neurohormonal stimuli was also measured. The results confirmed that totally obstructed glands undergo a rapid, progressive severe atrophy amounting to absolute losses of over 85% of acinar tissue by two weeks. Acinar shrinkage and cell losses through apoptosis accounted for the glandular atrophy. Remaining intralobular epithelia consisted of extremely atrophic acini and numerous duct-like structures with intermediate forms. Dispersed cells from atrophic glands exhibited agonist-induced release of chloride similar to normal. Together, these structural-functional results confirm the persistent viability of acinar-like cells in the obstructed gland and suggest that the duct-like structures are derived from surviving atrophic acini. De-ligated glands exhibited a near-normal recovery of structure by two weeks. Their enzymatically dispersed cells responded normally to agonist stimulation. The results support the view that pathological atrophy is largely similar to physiological atrophy, providing a mechanism for acinar cell survival under adverse conditions, with the possibility of eventual recovery.

Animals↗
PubMed1977

Rise of plasma corticosterone concentrations in rats immediately before and after birth and in fetal rats after the ligation of maternal uterine blood vessels or of the umbilical cord.

Just before normal vaginal delivery the plasma corticosterone concentration (PCC) in fetal rats increased markedly compared with that on day 22 of gestation. The PCC was elevated 2 h after birth and then declined until 12 h after birth, when it approached the level found on day 22 of gestation. Similarly, in premature newborn rats obtained by cesarean delivery on days 21 and 22 of gestation, the PCC increased 2 to 4 h after delivery and then declined. The PCC in 22-day-old fetal rats, 30 min after ligation of the maternal blood vessels running along a uterine horn, rose markedly compared with that in fetuses in the contralateral intact horn. A similar increase in PCC was not observed in either decapitated or encephalectomized fetuses, but observed in fetuses whose umbilical cords were ligated. The rise in fetal PCC after ligation of uterine blood vessels and of umbilical cords was considerably higher than that observed after various stresses reported by other investigators and also higher than that found 60 min after maternal adrenalectomy. The rise in PCC just before and just after birth and after the ligation should not be considered as the result of stress, parturition or ligation, but may be a result of the response to other factors.

Animals↗
PubMed1989

Effects of ligation of the ductus deferens on the fowl epididymal region.

The effects of ligation of the ductus deferens on the epididymis in the fowl were studied histochemically and immunohistochemically to reveal the mechanisms of sperm disposal. At one week post-ligation, the lumina of the rete testes (RT) and the efferent ductules (ED) were distended and filled with densely accumulated spermatozoa. Macrophages and foreign-body giant cells were aggregated in and around the accumulations. The epithelium regressed in the initial portion of the RT with the invasion of fibroblasts and heterophiles into the lumen. The other part of the epithelium was penetrated by many spermatozoa. Numerous lymphocytes and plasma cells infiltrated into the interstitium. At 4 weeks, larger number of spermatozoa agglutinated in the lumen, and large masses of foamy cells and proliferated connective tissue protruded into the lumen. At 8 weeks, large masses of foamy cells were noted. The connecting ductules or the epididymal duct showed no marked changes after ligation. The epithelium of the ED showed weaker or no acid phosphatase activity after ligation. Immunoglobulin G-containing cells increased in number in the interstitium. These results showed that ligation of the ductus deferens in the fowl causes granuloma in the RT and ED, and that epithelial cells, macrophages and granuloma are engaged in the removal of spermatozoa. The participation of antibody is suggested in the sperm disposal processes.

Animals↗
PubMed1992

Role of platelet-activating factor in pulmonary edema after coronary ligation in dogs.

To evaluate whether PAF is related to the precipitation of pulmonary edema after myocardial ischemia, we studied the effect of a specific PAF antagonist, CV-6209, on the extravascular lung water level measured by the thermal-dye double indicator dilution method, ETV, after coronary ligation in dogs. Eight dogs served as sham control animals (group 1). The proximal left anterior descending coronary artery was ligated for 45 min in eight dogs (group 2), and the coronary artery was ligated after pretreatment with CV-6209 (1 mg/kg) in eight dogs (group 3). The ETV increased significantly after coronary ligation in groups 2 and 3. The amount of increase in ETV in group 2 was significantly larger than in group 3. Thus, CV-6209 can prevent the accumulation of extravascular lung water after coronary ligation without producing changes in pulmonary vascular dynamics, indicating that PAF may play an important role in pulmonary edema after myocardial ischemia.

Animals↗
PubMed2002

Morphological changes in the rat exocrine pancreas after pancreatic duct ligation.

In the present study, morphological changes of the exocrine pancreas in rats after pancreatic duct ligation were examined with light microscopy (hematoxylin-eosin, TUNEL, and PCNA staining) and scanning electron microscopy in order to elucidate the effects of increased pancreatic duct pressure. On the fifth day after pancreatic duct ligation, ductular proliferation, periductal fibrosis, and disappearance of acini were observed. TUNEL and PCNA staining demonstrated many apoptotic acinar cells and proliferating ductal cells immediately after ligation, which reached a maximal number on the 2nd or 3rd day. Tortuous or helical interlobular pancreatic ducts with inner surfaces containing many crater-like depressions and long cilia were found after ligation. These changes were almost identical to those observed in the pancreatic tissue of model chronic pancreatitis rats, WBN/Kob rats, and stroke-prone spontaneously hypertensive (SHRSP) rats. In summary, the morphological changes observed after pancreatic duct ligation were similar to those of chronic pancreatitis, therefore, the characteristic changes of pancreatic ducts observed in chronic pancreatitis may be caused by increased pancreatic duct pressure.

Animals↗
PubMed1978

The influence of the testis on the fertilizing life of spermatozoa in the ligated vas deferens of the golden hamster.

Spermatozoa in the vas deferens of the hamster lose their fertilizing capacity 3 days after ligation of the initial part of the duct and after 2 days if the testes are removed at the time of ligation. Sham-ligation had no effect on the fertilizing life of vasal spermatozoa on the contralateral side even 3 days after bilateral castration. Unilateral castration for 3 days had no effect on the fertilizing capacity of spermatozoa from the ipsilateral unobstructed duct, whereas no eggs were fertilized by spermatozoa from the contralateral ligated duct associated with the remaining testis. Unlike testosterone, 5alpha-dihydrotestosterone injected daily or implanted subcutaneously in Silastic tubes maintained normal fertilizing capacity for 2 days in castrates and for 3 days in intact males. Within each group, ligation had no effect on the level of fructose in the seminal vesicle on that side compared with the level in the gland on the other side.

Androgens↗
PubMed2003

Arrested apoptosis without nuclear fragmentation produced by efferent duct ligation in round spermatids and multinucleated giant cells of rat testis.

The apoptotic process evoked by efferent duct ligation in the testes of adult rats was followed for 10 days by differential staining for haematoxylin-eosin, periodic acid-Schiff and a modified trichrome technique in optical microscopy and by ultrastructural localization of acid phosphatase. Round spermatids showed the first effects of efferent duct ligation. At day 3 after ligation, annular clumps of chromatin with typical apoptotic characteristics appeared against the nuclear membrane of these cells. Afterwards, membranous structures and a wide separation between the two layers of the nuclear membrane were observed but nuclear fragmentation did not occur and apoptotic granules were not seen. Cytoplasmic components were also altered, and severely damaged organoids and empty vacuoles lacking acid phosphatase reaction were frequently seen. On day 2 after efferent duct ligation, multinucleated giant cells appeared, which displayed similar characteristics as spermatids and showed no acid phosphatase reaction. Although abnormal spermatids and multinucleated giant cells were surrounded by the cytoplasm of Sertoli cells, neither lysosomal acid phosphatase nor phagocytic activity was detected. It is concluded that efferent duct ligation specifically affects round immature spermatids eliciting a partial nuclear apoptotic response that is not accompanied by autophagic or heterophagic activity and without lysosomal participation in Sertoli cells.

Acid Phosphatase↗
PubMed1979

Coronary collateral circulation as an important factor to modify the ischemic injury of the myocardium in coronary ligated dogs.

Effect of coronary ligation on epicardial and intramyocardial ST-segment voltage was investigated in 121 dogs. After ligation of the anterior descending coronary artery, marked ST-elevation, more than 2 mV, was detected in 102 dogs (Group-I) in epicardial lead of the area which was nourished by the ligated coronary artery. In 7 dogs (Group-II), coronary ligation produced negligible changes in ST-segment voltage in epicardial lead, while significant ST-elevation was observed in the leads of middle and inner layers of the myocardium. Systemic hemo-dynamic parameters showed no statistically significant difference between the 2 groups. Coronary collateral indices, however, revealed the significant difference between them. Systolic peripheral coronary pressure was 29.3 +/- 3.1 mmHg in Group-I and 59.2 +/- 10.6 mmHg in Group-II (P less than 0.05). Retrograde flow was also greater in Group-II (14.8 +/- 4.4 ml/min) than in Group-I (1.3 +/- 0.5 ml/min) (p less than 0.01). Diversion of retrograde flow produced a marked ST-elevation in Group-II. Restoration of retrograde flow to the myocardium immediately decreased the ST-segment voltage. These results suggest that spontaneously developed collaterals have an important function for the prevention of the occurrence of ischemic injury after coronary ligation in dogs.

Animals↗
PubMed2004

Bacteremia in cirrhotic patients submitted to endoscopic band ligation of esophageal varices.

BACKGROUND: Endoscopic procedures can develop bacteremia. Patients with chronic liver disease are more predisposed to undergo bacteremia and infections because they are immunocompromised. AIMS: The purpose of this study was to determine the incidence of bacteremia in cirrhotics submitted to endoscopic variceal ligation. METHODS: Three groups of 40 patients each were studied. One group was made up of patients with cirrhosis who were submitted to ligation, a second group was composed of cirrhotics who underwent esophagogastroduodenoscopy only, and a third group was composed of patients without liver disease who underwent esophagogastroduodenoscopy. Blood was sampled from all patients for culture, both in aerobic and in anaerobic mediums, immediately before endoscopy and at 5 and 30 minutes after its completion. RESULTS: Blood culture was positive in 6 samples. In 4 of these, the bacteria (Staphylococcus hominis hominis, Staphylococcus auricularis, Acinetobacter lwoffii, and coagulase-negative staphylococcus) were isolated before the endoscopic procedure and thus were considered as contamination. In the ligation group, a streptococcus of the viridans group was isolated 5 minutes after the procedure, and in the cirrhosis without ligation group, a Staphylococcus epidermidis was isolated at 30 minutes. None of the patients showed clinical evidence of infection. CONCLUSIONS: The bacteremia incidence in cirrhotic patients submitted to variceal ligation was 2.5%, showing no difference from the control groups.

Bacteremia↗
PubMedDate not supplied

Prenatal tracheal ligation or intra-amniotic administration of surfactant or dexamethasone prevents some structural changes in the pulmonary arteries of surgically created diaphragmatic hernia in rabbits.

PURPOSE: Characterization of the structural changes occurring in the pulmonary arteries resulting from surgically produced congenital diaphragmatic hernia in rabbits, with particular emphasis on the preventive effects of prenatal tracheal ligation or administration of intra-amniotic dexamethasone or surfactant. METHODS: Twenty rabbit fetuses underwent surgical creation of a left-sided congenital diaphragmatic hernia on the 24th or 25th gestational day. They were divided according to the following procedures: congenital diaphragmatic hernia (n = 5), congenital diaphragmatic hernia plus tracheal ligation (n = 5), congenital diaphragmatic hernia plus intra-amniotic administration of dexamethasone 0.4 mg (n = 5) or surfactant (Curosurf 40 mg, n = 5). On gestational day 30, all the fetuses were delivered by caesarean section and killed. A control group consisted of five nonoperated fetuses. Histomorphometric analysis of medial thickness, cell nuclei density, and elastic fiber density of pulmonary arterial walls was performed. RESULTS: Arteries with an external diameter > 100 microm have a decreased medial thickness, lower cell nuclei density, and greater elastic fiber density when compared with arteries with external diameter < or = 100 microm. Congenital diaphragmatic hernia promoted a significant decrease in medial thickness and an increase in cell nuclei density in artery walls with external diameter > 100 microm. Prenatal treatments with tracheal ligation or intra-amniotic administration of dexamethasone or surfactant prevented these changes. In arteries with external diameter < or = 100 microm, congenital diaphragmatic hernia promoted a significant increase in medial thickness and in cell nuclei density and a decrease in elastic fiber density. The prenatal treatments with tracheal ligation or intra-amniotic administration of dexamethasone or surfactant prevented these changes, although no effect was observed in elastic fiber density in the congenital diaphragmatic hernia plus dexamethasone group. CONCLUSIONS: Congenital diaphragmatic hernia promoted different structural changes for large or small arteries. The prenatal intra-amniotic administration of dexamethasone or surfactant had positive effects on the lung structural changes promoted by congenital diaphragmatic hernia, and these effects were comparable to the changes induced by tracheal ligation.

Amnion↗
PubMed2003

Infrared coagulation versus rubber band ligation in early stage hemorrhoids.

The ideal therapy for early stages of hemorrhoids is always debated. Some are more effective but are more painful, others are less painful but their efficacy is also lower. Thus, comfort or efficacy is a major concern. In the present randomized study, a comparison is made between infrared coagulation and rubber band ligation in terms of effectiveness and discomfort. One hundred patients with second degree bleeding piles were randomized prospectively to either rubber band ligation (N = 54) or infrared coagulation (N = 46). Parameters measured included postoperative discomfort and pain, time to return to work, relief in incidence of bleeding, and recurrence rate. The mean age was 38 years (range 19-68 years). The mean duration of disease was 17.5 months (range 12 to 34 months). The number of male patients was double that of females. Postoperative pain during the first week was more intense in the band ligation group (2-5 vs 0-3 on a visual analogue scale). Post-defecation pain was more intense with band ligation and so was rectal tenesmus (P = 0.0059). The patients in the infrared coagulation group resumed their duties earlier (2 vs 4 days, P = 0.03), but also had a higher recurrence or failure rate (P = 0.03). Thus, we conclude that band ligation, although more effective in controlling symptoms and obliterating hemorrhoids, is associated with more pain and discomfort to the patient. As infrared coagulation can be conveniently repeated in case of recurrence, it could be considered to be a suitable alternative office procedure for the treatment of early stage hemorrhoids.

Adult↗
PubMed2006

[Esophageal motility studies in cirrhotic patients before and after endoscopic variceal ligation].

BACKGROUND: To study esophageal motility before and after the endoscopic variceal ligation in cirrhotic patients. METHODS: Twenty-four patients with chronic liver disease assisted at the "Gastrocentro - UNICAMP" in the program of endoscopic variceal ligation were studied (mean age of 49.5 years, 19 males and 5 females). The inclusion criteria were chronic liver disease and esophageal varices with high-risk bleeding. Initially upper digestive endoscopy and esophageal manometry were performed in all cases. Next, the sessions of variceal ligation were initiated (average 3.4+/-2.1) in the outpatient clinic, with an interval of 2 to 4 weeks. The esophageal manometry was repeated 4 weeks after variceal eradication and amplitude, duration, propagation speed of the contractile waves and peristalsis were studied. RESULTS: Analysis of the lower sphincter pressure did not show differences before and after variceal ligation. In 10 cases (41.6%) dysmotility was recorded, and the amplitude of the contractile waves rose from 70.7 mmHg (52.3 and 108.4) before variceal ligation to 89.7 mmHg (69.9 and 122.8) after the procedure (p = 0.004 - p < 0.05), and the duration increased from 3.55 seg.+/- 0.58 to 3.90 seg.+/- 0.72 (p = 0.02 - p < 0.05). The wave propagation speed did not differ from the values before the exam of 3.43+/- 0.97 cm/seg, to those after of. 61+/- 0.99 cm/sec (p = 0.15 - p > 0.05). CONCLUSION: The final analysis shows alterations of esophageal motility characterized by increase in the amplitude and duration of the contractile waves.

Esophageal Motility Disorders↗
PubMed1999

Enteral IGF-I enhances fetal growth and gastrointestinal development in oesophageal ligated fetal sheep.

Infants with upper gut atresia often have impaired intrauterine growth and gut function. IGF-I is important in fetal growth and is contained in amniotic fluid. We therefore wanted to test the hypothesis that IGF-I infused into fetal gut would reverse the effects of an upper gut obstruction on gut structure and growth in fetal sheep. At 90 days gestation fetuses (n=6 per group) underwent oesophageal ligation, followed by continuous infusion of IGF-I (1-8 microgram/day) or saline into the gut beyond the ligation until 137 days. Controls underwent sham ligation only. Oesophageal ligation tended to reduce fetal body and organ weights. IGF-I treatment prevented this reduction and increased body length and spleen weight above those of controls. The decrease in bowel wall thickness induced by oesophageal ligation was also prevented by IGF-I treatment. Amniotic fluid IGF-I concentrations did not change over gestation and were higher in the IGF-I treated group. No change in fetal plasma IGF-I concentrations were detectable. We conclude that enterally administered IGF-I may enhance fetal growth and gut development in utero and that IGF-I in amniotic fluid may play a physiological role in gut development in the fetus.

Animals↗