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1.
Compend Contin Educ Dent ; 43(5): E9-eE12, 2022 May.
Article in English | MEDLINE | ID: mdl-35523317

ABSTRACT

Rubber dams are frequently used to enable clinicians to achieve better visualization and isolation for dental procedures. Growing in popularity thanks in part to an increasing number of techniques facilitating their placement, rubber dams are able to be used for myriad restorative procedures, including crown and veneer preparation and cementation. An effect of rubber dam use is reduction of saliva, which causes temporary dehydration of the isolated teeth. In turn, this dehydration affects shade matching, an important aspect of esthetic outcomes. The purpose of this study was to determine the extent that shade is altered from baseline due to dehydration from rubber dam use during restorative procedures, and, furthermore, to determine the length of time required for teeth to rehydrate back to their baseline shade.


Subject(s)
Dehydration , Tooth , Crowns , Esthetics, Dental , Humans , Rubber Dams
2.
Compend Contin Educ Dent ; 43(5): E13-eE16, 2022 May.
Article in English | MEDLINE | ID: mdl-35523318

ABSTRACT

Social media has flooded the Internet with beautiful "before and after" photographs of porcelain restorations. While these images can help promote the benefits of cosmetic dentistry, one of the problems this can lead to is patients mistakenly assuming that such restorations are simple to achieve. They may fail to realize that multiple steps need to be taken to attain such esthetic results, with each step requiring meticulous attention to detail. What some patients may not appreciate is the precision that goes into every step and which is critical to achieving long-term success. From preparation design and material choice, to selecting the correct bonding protocol and cements, no steps in the restorative process can be overlooked or deemed less important than others. The case presented describes a smile rehabilitation with proper isolation and cementation protocols.


Subject(s)
Dental Porcelain , Esthetics, Dental , Cementation/methods , Humans
3.
Compend Contin Educ Dent ; 43(5): 292-297, 2022 May.
Article in English | MEDLINE | ID: mdl-35589148

ABSTRACT

To achieve excellence in dentistry, a multitude of steps needs to be completed. From performing a thorough history, to diagnosis and treatment planning, all the way to accurate insertion of the restorations, every aspect of the restorative process requires careful thought and precision, especially in a complex case. This article describes a stepwise approach to completing a full-mouth rehabilitation using an entirely digital approach. Additionally, it discusses ideal measures of isolation and bonding as pertaining to all-ceramic restorations. Through utilizing a systematic strategy, the clinician can establish a predictable path to ensure a successful result.


Subject(s)
Computer-Aided Design , Mouth Rehabilitation , Ceramics , Esthetics, Dental , Workflow
4.
Eur Rev Med Pharmacol Sci ; 22(20): 7039-7044, 2018 10.
Article in English | MEDLINE | ID: mdl-30402872

ABSTRACT

OBJECTIVE: In the last years, the mean age of women who underwent cervical treatment for high-grade cervical intraepithelial neoplasia (CIN 2-3) is similar to the age of women having their first pregnancy. The aim of this study was to evaluate the risk of preterm birth in subsequent pregnancies after loop electrosurgical excision procedure (LEEP). PATIENTS AND METHODS: From January 2013 to January 2016 the study identified a total of 1435 women, nulliparous, who underwent LEEP for CIN 2-3, and who wished to have their first pregnancy. Before surgery, the lengths of the cervix were calculated by transvaginal sonography. After the treatment, the dimension of the removed tissue was evaluated. During the pregnancy, all women carried out periodic transvaginal sonography and vaginal-cervical swabs. RESULTS: The average age of patients was 31.96±5.24 years; the interval between the surgical procedure and pregnancy was 12.04±4.67 months; the gestational age at births was 37.53±2.91 weeks. The first vaginal and cervical swab performed during pregnancy was negative in 81.8% of patients. The most prevalent infections were related to C. Albicans, G. Vaginalis, and Group B Streptococcus (GBS). The rate of preterm delivery was significantly higher in women with a minor cervical length. CONCLUSIONS: The length and the volume of cervical tissue excised have been shown to be directly related to the risk for preterm birth. Furthermore, vaginal infections and their persistence during pregnancy in women with a history of LEEP may be associated with an increased risk for preterm birth, compared with women with no history of LEEP.


Subject(s)
Electrosurgery/methods , Microbiota , Pregnancy Outcome , Premature Birth/epidemiology , Adult , Female , Gestational Age , Humans , Infant, Newborn , Pregnancy , Prevalence , Risk Factors , Uterine Cervical Neoplasms/surgery , Uterine Cervical Dysplasia/surgery
5.
Eur J Pediatr ; 175(1): 121-30, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26272254

ABSTRACT

Subclinical cardiac abnormalities represent predisposing factors for cardiovascular disease (CVD) in obese subjects. The aim of this study was to evaluate early cardiac abnormalities in obese youth and the potential association with insulin resistance (IR). Thirty obese (12 males (M)/18 females (F); age = 11.5 ± 2.4 years; body mass index (BMI)-standard deviation score (SDS) = +2.1 ± 0.5) and 15 normal weight (10 M/5 F; age = 12.8 ± 3.1 years; BMI-SDS = +0.3 ± 0.9) children and adolescents underwent Doppler two-dimensional echocardiographic assessments of left atrial (LA) and ventricular (LV) geometry and LV diastolic function (peak early [E] and late waves, E wave deceleration time, myocardial flow velocities). Homeostasis model assessment of IR (HOMA-IR) was used as an IR index. LA size was increased in obese children, as indicated by higher LA diameter (4.9 ± 0.5 vs 4.1 ± 0.4 cm, p < 0.001), area (14.3 ± 2.5 vs 10.7 ± 2.0 cm(2), p < 0.001), and volume (33.8 ± 10.6 vs 23.7 ± 6.4 ml, p = 0.003). LV mass was also increased in obese children (87.0 ± 16.6 vs 68.8 ± 13.2 g, p = 0.003), who also showed subtle diastolic dysfunctions, as indicated by higher values of E (97.1 ± 14.3 vs 86.2 ± 11.9 cm/s, p = 0.02). All the above parameters were significantly associated with BMI-SDS (p < 0.05). In addition, HOMA-IR was independently associated with LA diameter, area, and volume (ß = 0.314, p = 0.040; ß = 0.415, p = 0.008; ß = 0.535, p = 0.001). CONCLUSION: Obese children feature increased LA size, which emerged to be mainly correlated to, and possibly driven by IR, suggesting an increased CVD risk. WHAT IS KNOWN: Left atrial and ventricular alterations have been reported in obese adults, and they represent predisposing factors for cardiovascular disease. There is some evidence suggesting that obese children show increased left ventricular mass and also increased atrial size, although with conflicting results. WHAT IS NEW: Obese normotensive children showed a moderately increased atrial size, subtle alterations in left cardiac diastolic function, and ventricular mass. An association between insulin resistance and left cardiac changes was found, although its mechanism remains to be determined.


Subject(s)
Heart Atria/pathology , Insulin Resistance/physiology , Pediatric Obesity/pathology , Adolescent , Anthropometry , Blood Pressure , Cardiovascular Diseases/etiology , Child , Diastole/physiology , Diastole/radiation effects , Echocardiography, Doppler , Female , Humans , Male , Pilot Projects , Risk Factors
6.
Nutr Metab Cardiovasc Dis ; 24(1): 75-82, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23809150

ABSTRACT

BACKGROUND AND AIMS: The Mediterranean diet has been recognised as having a protective role on the cardiovascular system due to its low lipid and high antioxidant content. Lipid profile and oxidant status represent two important risk factors related to endothelial dysfunction, even at early stages of cardiovascular diseases. The aim of the study was to evaluate the influence of a 12-month Mediterranean diet on the variation of lipid profile and carotid intima-media thickness (cIMT) in pre-pubertal hypercholesterolaemic children. METHODS AND RESULTS: We performed a cross-sectional study comparing lipid profile and cIMT in a group of 68 pre-pubertal children (36 with hypercholesterolaemia and 32 controls). In addition, in the hypercholesterolaemic children a 12-month intervention programme with a Mediterranean diet was started to evaluate the variation of lipid profile and cIMT. At baseline, hypercholesterolaemic children showed a significantly higher cIMT (both right and left carotid artery) compared to controls (both p < 0.05). After 12 months of diet intervention, a significant reduction of total cholesterol, LDL-cholesterol and cIMT was documented (all p < 0.05). Furthermore, at the end of follow-up, delta body mass index-Standard Deviation score and delta LDL-cholesterol were significantly and independently related to the changes of cIMT (both p < 0.05). CONCLUSION: The Mediterranean diet represents a valid approach in the treatment of hypercholesterolaemia even during childhood.


Subject(s)
Carotid Intima-Media Thickness , Diet, Mediterranean , Hypercholesterolemia/diet therapy , Apolipoprotein A-I/blood , Apolipoproteins B/blood , Blood Glucose/metabolism , Body Mass Index , Case-Control Studies , Child , Child, Preschool , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Cross-Sectional Studies , Electric Impedance , Female , Follow-Up Studies , Humans , Insulin/blood , Linear Models , Male , Risk Factors
7.
Free Radic Res ; 47(3): 146-53, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23205728

ABSTRACT

In obese adults with non alcoholic fatty liver disease (NAFLD), treatment with Vitamin E has resulted in an improvement in liver histology, whereas variable and limited results are available in children. Our aim was to assess whether lifestyle combined with supplementation with Vitamin E might reduce oxidative stress and improve cardio-metabolic status in obese children with NAFLD. 24 obese prepubertal children (16M) followed a 6-month lifestyle intervention combined with Vitamin E supplementation (600 mg/day) and they were compared with 21 age and sex-matched obese peers who underwent lifestyle intervention only. At baseline and after 6-month urinary prostaglandin F2α (PGF-2α), endogenous secretory receptor for advanced glycation end products (esRAGE), high sensitivity C-reactive protein (hs-CRP), alanine aminotransferases (ALT), lipid profile, glucose, and insulin were assessed. The two groups were comparable for age (8.3 ± 1.6 vs 8.4 ± 1.3 yr), sex and BMI SDS (2.16 ± 0.29 vs 2.13 ± 0.28). At the beginning of the study, PGF2-α, esRAGE hsCRP, ALT, lipid profile and HOMA-IR levels were similar between the two groups (all p > 0.05). After 6-month treatment, levels of PGF2-α (p < 0.001) significantly decreased and esRAGE significantly increased (p < 0.001) in children treated with Vitamin E. A significant reduction was also found in ALT (p = 0.001), lipid profile and HOMA-IR (p < 0.001). In contrast, no significant change in any of these markers was detected in the lifestyle only group. In conclusion, Vitamin E supplementation was associated with a significant reduction in oxidative stress and improved cardio-metabolic alterations. These data suggest that Vitamin E supplementation could represent a valuable treatment in obese children affected by NAFLD.


Subject(s)
Fatty Liver/therapy , Life Style , Obesity/therapy , Oxidative Stress , Vitamin E/administration & dosage , Body Mass Index , Child , Diet , Exercise Therapy , Fatty Liver/metabolism , Fatty Liver/pathology , Female , Humans , Lipids/blood , Male , Obesity/metabolism , Obesity/pathology
8.
Phytomedicine ; 18(10): 879-86, 2011 Jul 15.
Article in English | MEDLINE | ID: mdl-21397481

ABSTRACT

Genistein aglycone (GEN) has a favorable effect on bone loss. We investigated the effects of GEN alone or in combination with supplemental calcium and vitamin D(3) in an animal model of bone loss to evaluate if there was additional benefit. Ovariectomized (OVX) and SHAM-OVX rats were used. OVX were divided into 12 groups and randomized to receive: GEN at 27, 54, 200, 500 or 1000 mg (human equivalent dose (HED)/day/ip injection alone or with calcium carbonate (Ca) (360 mg/kg/day/gavages) and vitamin D(3) (D(3)) (50 IU/kg/day/gavages) or Ca/D(3) without GEN or untreated for 6 weeks. SHAM-OVX were randomized into 7 groups and treated with: Ca and D(3) alone or in combination with GEN (same doses as OVX), or left untreated. Bone mineral density (BMD), bone-alkaline phosphatase (b-ALP), collagen C-telopeptides (CTX), osteoprotegerin (OPG) and soluble receptor activator of NFκB ligand (sRANKL) were assessed. Femurs were excised and tested for breaking strength and histology. Uterine weight was analyzed to assess GEN's estrogenic effects on the SHAM-OVX. The most effective dose of GEN, independent of Ca/D(3) supplementation, was 54 mg/day. Higher doses yielded no further improvement in bone biomarkers, histology or strength. Only 1000 mg/day HED of genistein produced statistically significant changes in uterine weight of the SHAM-OVX. This study suggests that 54 mg/day of GEN is the threshold dose for efficacy. In addition, supplemental calcium and vitamin D(3), beyond normal dietary intake do not enhance the effects of genistein on improving measures of bone loss. This observation has implications regarding the use of calcium and vitamin D(3) supplementation.


Subject(s)
Bone Diseases, Metabolic/drug therapy , Calcium Carbonate/pharmacology , Cholecalciferol/pharmacology , Genistein/therapeutic use , Alkaline Phosphatase/metabolism , Animals , Bone Density , Bone Density Conservation Agents/administration & dosage , Bone Density Conservation Agents/pharmacology , Compressive Strength , Disease Models, Animal , Drug Therapy, Combination , Female , Femur/anatomy & histology , Femur/drug effects , Genistein/administration & dosage , Osteoprotegerin/drug effects , Ovariectomy , Plant Extracts/administration & dosage , Plant Extracts/therapeutic use , RANK Ligand/metabolism , Random Allocation , Rats , Rats, Sprague-Dawley , Sophora/chemistry , Uterus/drug effects
9.
Br J Pharmacol ; 160(5): 1185-94, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20590611

ABSTRACT

BACKGROUND AND PURPOSE: Oestrogen loss at menopause is frequently related to poor wound healing. Genistein has been tested in anti-ageing cosmetic preparations with interesting results on skin health. Here, we investigated the effects of the genistein aglycones, given systemically, in an incisional model of wound healing, compared to systemic oestradiol and raloxifene. EXPERIMENTAL APPROACH: Six months after ovariectomy (OVX), rats were randomly assigned to groups of 12 animals each and treated daily with genistein aglycone (1 and 10 mg kg(-1) s.c.), raloxifene hydrochloride (0.05 and 0.5 mg kg(-1) s.c.) or 17-alpha-ethinyl oestradiol (0.003 and 0.03 mg kg(-1) s.c.) for 12 weeks. Untreated OVX and sham OVX rats were used as controls. Then, 14 or 7 days before the end of the experiment, an incisional wound healing procedure was performed and skin specimens were collected to evaluate molecular, histological and functional measurements. KEY RESULTS: Seven and fourteen days after wounding, samples from OVX rats showed a decrease in transforming growth factor-beta1, tissue transglutaminase 2 and vascular endothelial growth factor compared to samples from sham OVX rats. Oestradiol, raloxifene and genistein all significantly modified this decrease, but the lowest genistein dose exerted a greater effect than the other treatments. Moreover, the lowest dose of genistein was the most effective in improving skin healing and wound tensile strength. CONCLUSIONS AND IMPLICATIONS: Genistein aglycone might be an alternative therapy for the management of skin wound healing.


Subject(s)
Ethinyl Estradiol/administration & dosage , Genistein/administration & dosage , Phytoestrogens/administration & dosage , Raloxifene Hydrochloride/administration & dosage , Skin/drug effects , Wound Healing/drug effects , Animals , Dermatologic Surgical Procedures , Disease Models, Animal , Dose-Response Relationship, Drug , Female , GTP-Binding Proteins/metabolism , Ovariectomy , Protein Glutamine gamma Glutamyltransferase 2 , Random Allocation , Rats , Rats, Sprague-Dawley , Skin/metabolism , Skin/pathology , Tensile Strength/drug effects , Transforming Growth Factor beta1/metabolism , Transglutaminases/metabolism , Vascular Endothelial Growth Factor A/metabolism
10.
Diabetologia ; 53(6): 1199-209, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20204321

ABSTRACT

AIMS/HYPOTHESIS: A high but normal fasting plasma glucose level in adults is a risk factor for future development of type 2 diabetes mellitus and cardiovascular disease. We investigated whether normal fasting plasma glucose levels (<5.60 mmol/l) are associated with decreases in insulin sensitivity and beta cell function, as well as an adverse cardiovascular profile in obese youth. METHODS: We performed a cross-sectional analysis in a multiethnic sample of 1,020 obese youth (614 girls and 406 boys; mean age 12.9 years [CI 95% 12.7-13.1], BMI z score 2.34 [CI 95% 2.31-2.38]) with normal fasting plasma glucose. All participants had a standard OGTT, with calculation of indices of insulin sensitivity and beta cell function. For the analysis, prepubertal and pubertal participants were stratified into quartiles of normal fasting plasma glucose. RESULTS: We observed a significant increase in fasting insulin and AUC 2 h glucose across quartiles. Pronounced changes were observed in insulin sensitivity and secretion, particularly in the pubertal group. Moreover, the odds of presenting with impaired glucose tolerance increased by 4.5% with each 0.06 mmol/l increase in fasting plasma glucose. No significant differences in cardiovascular indices were seen across quartiles. CONCLUSIONS/INTERPRETATION: These data suggest that in obese youth, independent of age, BMI z score, sex, family history and ethnicity, insulin sensitivity and secretion decline when moving from low to high normal fasting plasma glucose. The simple measure of fasting plasma glucose could assist clinicians in identifying children for targeted diabetes screening and subsequent lifestyle management.


Subject(s)
Blood Glucose , Insulin Resistance , Insulin-Secreting Cells/metabolism , Obesity/metabolism , Adolescent , Analysis of Variance , Area Under Curve , Child , Cross-Sectional Studies , Fasting , Female , Humans , Insulin/blood , Male , Predictive Value of Tests , Regression Analysis , Risk Factors
11.
Nutr Metab Cardiovasc Dis ; 20(5): 332-40, 2010 Jun.
Article in English | MEDLINE | ID: mdl-19631515

ABSTRACT

BACKGROUND AND AIM: Recent evidence suggests that genistein aglycone may act beneficially on surrogate cardiovascular risk markers in postmenopausal women. We assessed the effects of genistein aglycone on some cardiovascular risk factors and homocysteine levels after 3-years of continued therapy in a cohort of osteopenic, postmenopausal women. METHODS AND RESULTS: The parent study was a randomized, double-blind, placebo-controlled trial involving 389 postmenopausal women with low bone mass for 24 months. Subsequently, a subcohort (138 patients) continued therapy for an additional year. Participants received 54mg of genistein aglycone (n=71) or placebo (n=67), daily. Both arms received calcium and vitamin D(3) in therapeutic doses. Moreover, 4 weeks before randomization procedures and during our follow-up study, all patients received dietary instructions in an isocaloric fat-restricted diet. Blood lipid profiles, fasting glucose and insulin, insulin resistance (HOMA-IR), fibrinogen, osteoprotegerin (OPG) and homocysteine at baseline and after 24 and 36 months of treatment were measured. Compared to placebo, genistein significantly decreased fasting glucose and insulin, HOMA-IR, fibrinogen and homocysteine after 24 and 36 months of treatment. By contrast, isoflavone administration did not affect high-density lipoprotein cholesterol and triglycerides though serum OPG was higher in the genistein recipients. There were no differences in adverse events or discomfort between groups. Results on routine biochemical, liver function, and hematologic testing did not change over time in placebo or genistein group. CONCLUSIONS: After 3-years of treatment, genistein aglycone plus calcium, vitamin D(3) and a healthy diet showed positive effects on some cardiovascular risk factors and homocysteine levels in a cohort of postmenopausal women with low bone mass.


Subject(s)
Cardiovascular Diseases/prevention & control , Genistein/pharmacology , Homocysteine/blood , Calcium Carbonate/administration & dosage , Cholecalciferol/administration & dosage , Female , Follow-Up Studies , Genistein/adverse effects , Humans , Insulin Resistance , Lipids/blood , Middle Aged , Osteoprotegerin/blood , Postmenopause , Research Design , Risk Factors
12.
Drug Saf ; 22(4): 251-62, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10789822

ABSTRACT

Dobutamine stress echocardiography is considered a relatively well-tolerated diagnostic modality, effective in the management of patients with known or suspected coronary artery disease. Adverse effects during testing are relatively frequent, precluding the achievement of a diagnostic end-point in about 5 to 10% of tests. These adverse effects, mostly tachyarrhythmias and arterial hypotension, are usually minor and self limiting. However, severe life-threatening complications, as well as death, also occur. By analysing Medline-quoted literature up to March 1999, we found 35 original studies from a single institution with more than 100 patients, as well as 2 multicentre studies, concerning the feasibility and safety of dobutamine stress echocardiography. In a cumulative total of 26438 tests performed, 79 life-threatening complications (such as acute myocardial infarction, asystole, ventricular fibrillation, sustained ventricular tachycardia or severe symptomatic hypotension) have been reported, giving an incidence of 1 severe adverse reaction per every 335 examinations. In addition, 29 isolated case reports have been published describing life-threatening complications during dobutamine echocardiography. In case reports, 2 deaths have been described, both due to acute cardiac rupture in patients with recent inferior myocardial infarction. Severe adverse reactions during dobutamine echocardiography can be ischaemia independent, and are independent of operator experience and are unpredictable; some complications can be late occurring and long lasting. As a consequence, the procedure must be clearly indicated, written informed consent has to be obtained from the patient, an attending physician must be present during testing, and long term observation of outpatients is useful in order to manage late complications. In conclusion, while the safety of dobutamine stress echocardiography was reported to be outstanding in early reports, further experience presents a substantially more worrying picture. This must be taken into account by both physicians and patients when assessing the risk-benefit profile of the procedure.


Subject(s)
Arrhythmias, Cardiac/chemically induced , Cardiotonic Agents/adverse effects , Coronary Disease/diagnosis , Dobutamine/adverse effects , Echocardiography/adverse effects , Hypotension/chemically induced , Clinical Trials as Topic , Exercise Test , Humans
13.
Arch Ital Biol ; 131(2-3): 235-43, 1993 Apr.
Article in English | MEDLINE | ID: mdl-8101707

ABSTRACT

In rat duodenal segments in vitro, electrical field stimulation induced a TTX-sensitive relaxation in the presence of atropine and guanethidine. A correlation between the amplitude of the evoked response and stimulus frequency was observed. Opioid peptides DAGO, DPDPE and DYN caused a dose-dependent increase in the amplitude of the response to EFS. Naloxone shifted to the right the dose-response curves for each opioid peptide significantly enhancing the ED50 values. The amplitude of the response to EFS was enhanced, dose-dependently, also in the presence of 5-HT. Such an effect induced by 5-HT was prevented by 5-HT receptor desensitization, but persisted unchanged after naloxone pretreatment. Opioids failed to affect the response to EFS after 5-HT receptor desensitization. Results suggest that in rat duodenum opioids modulate NANC inhibitory neurotransmission, indirectly the release of 5-HT.


Subject(s)
Autonomic Nervous System/drug effects , Duodenum/innervation , Endorphins/physiology , Serotonin/physiology , Synaptic Transmission/drug effects , Analgesics/pharmacology , Animals , Atropine/pharmacology , Duodenum/drug effects , Dynorphins/pharmacology , Electric Stimulation , Enkephalin, Ala(2)-MePhe(4)-Gly(5)- , Enkephalin, D-Penicillamine (2,5)- , Enkephalins/pharmacology , Gastrointestinal Motility/drug effects , Guanethidine/pharmacology , In Vitro Techniques , Male , Muscle Contraction/drug effects , Naloxone/pharmacology , Rats , Rats, Wistar , Tetrodotoxin/pharmacology
15.
Eur J Pharmacol ; 182(3): 487-95, 1990 Jul 17.
Article in English | MEDLINE | ID: mdl-1977591

ABSTRACT

The possible involvement of purines in the non-adrenergic non-cholinergic (NANC) relaxation of rat duodenum was studied using an isometric-isovolumic preparation. Purines (adenosine, AMP, ADP, ATP) induced a concentration-dependent, tetrodotoxin (TTX)-insensitive, fall in both endoluminal pressure and isometric tension. The relaxation induced by adenosine and by 2-chloroadenosine was selectively antagonized by 8-phenyltheophylline (1, 10 nM, 0.5 microM) and the ATP-induced relaxation was opposed by alpha, beta-methylene ATP (10 microM) and by reactive blue 2 (10 microM). Electrical field stimulation (EFS) caused TTX-sensitive inhibitory effects similar to those induced by ATP. None of the purinergic antagonists used were capable of affecting the EFS-induced relaxation. Our results indicate that both P1 and P2 purinoreceptors are present in muscle of the rat duodenum and are not involved in the NANC relaxation.


Subject(s)
Autonomic Nervous System/physiology , Duodenum/innervation , Neurotransmitter Agents/physiology , Purines/pharmacology , Adenosine/analogs & derivatives , Adenosine/pharmacology , Adenosine Diphosphate/pharmacology , Adenosine Monophosphate/pharmacology , Adenosine Triphosphate/pharmacology , Animals , Duodenum/physiology , Electric Stimulation , In Vitro Techniques , Male , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Rats , Rats, Inbred Strains , Tetrodotoxin/pharmacology , Theophylline/analogs & derivatives , Theophylline/pharmacology
16.
Arch Int Physiol Biochim ; 98(1): 35-40, 1990 Mar.
Article in English | MEDLINE | ID: mdl-1692692

ABSTRACT

Isolated rat duodenum shows spontaneous mechanical and electrical activities. Mechanical activity consists in changes both in endoluminal pressure and in isometric tension. Electrical activity is characterized by slow waves with superimposed bursts. This spontaneous activity is tetrodotoxin (TTX) resistant and therefore it is myogenic in origin. Indeed, TTX pretreatment, even in the presence of atropine and guanethidine, caused an increase in amplitude and in frequency of the electrical and mechanical activities. This finding indicates the presence of tonically active inhibitory intramural non adrenergic, non cholinergic (NANC) nerves. Duodenal longitudinal strips showed a spontaneous mechanical activity resembling that one recorded from isolated segment. Instead, circular strips are quiescent under resting condition and a contractile activity can be detected only after TTX pretreatment suggesting that: i) the circular smooth muscle layer is tonically inhibited by intramural NANC nerves and, ii) the contractions observed in the rat duodenum are due to the activity of the longitudinal one.


Subject(s)
Duodenum/physiology , Gastrointestinal Motility/physiology , Muscle, Smooth/physiology , Animals , Biomechanical Phenomena , Electrophysiology , In Vitro Techniques , Male , Rats
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