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1.
Surg Endosc ; 37(3): 1629-1648, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36781468

RESUMEN

BACKGROUND: In recent years, the use of Indocyanine Green (ICG) fluorescence-guided surgery during open and laparoscopic procedures has exponentially expanded across various clinical settings. The European Association of Endoscopic Surgery (EAES) initiated a consensus development conference on this topic with the aim of creating evidence-based statements and recommendations for the surgical community. METHODS: An expert panel of surgeons has been selected and invited to participate to this project. Systematic reviews of the PubMed, Embase and Cochrane libraries were performed to identify evidence on potential benefits of ICG fluorescence-guided surgery on clinical practice and patient outcomes. Statements and recommendations were prepared and unanimously agreed by the panel; they were then submitted to all EAES members through a two-rounds online survey and results presented at the EAES annual congress, Barcelona, November 2021. RESULTS: A total of 18,273 abstracts were screened with 117 articles included. 22 statements and 16 recommendations were generated and approved. In some areas, such as the use of ICG fluorescence-guided surgery during laparoscopic cholecystectomy, the perfusion assessment in colorectal surgery and the search for the sentinel lymph nodes in gynaecological malignancies, the large number of evidences in literature has allowed us to strongly recommend the use of ICG for a better anatomical definition and a reduction in post-operative complications. CONCLUSIONS: Overall, from the systematic literature review performed by the experts panel and the survey extended to all EAES members, ICG fluorescence-guided surgery could be considered a safe and effective technology. Future robust clinical research is required to specifically validate multiple organ-specific applications and the potential benefits of this technique on clinical outcomes.


Asunto(s)
Colecistectomía Laparoscópica , Laparoscopía , Humanos , Verde de Indocianina , Consenso , Fluorescencia , Laparoscopía/métodos
2.
Updates Surg ; 74(5): 1749-1754, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35416585

RESUMEN

The complexity of handheld steerable laparoscopic instruments (SLI) may impair the learning curve compared to conventional instruments when first utilized. This study aimed to provide the current state of interest in the use of SLI, the current use of these in daily practice and the type of training which is conducted before using SLI in the operating room (OR) on real patients. An online survey was distributed by European Association of Endoscopic Surgery (EAES) Executive Office to all active members, between January 4th and February 3rd, 2020. The survey consisted of 14 questions regarding the usage and training of steerable laparoscopic instruments. A total of 83 members responded, coming from 33 different countries. Twenty three percent of the respondents using SLI, were using the instruments routinely and of these 21% had not received any formal training in advance of using the instruments in real patients. Of all responding EAES members, 41% considered the instruments to potentially compromise patient safety due to their complexity, learning curve and the inexperience of the surgeons. The respondents reported the three most important aspects of a possible steerable laparoscopic instruments training curriculum to be: hands-on training, safe tissue handling and suturing practice. Finally, a major part of the respondents consider force/pressure feedback data to be of significant importance for implementation of training and assessment of safe laparoscopic and robotic surgery. Training and assessment of skills regarding safe implementation of steerable laparoscopic instruments is lacking. The respondents stressed the need for specific hands-on training during which feedback and assessment of skills should be guaranteed before operating on real patients.


Asunto(s)
Laparoscopía , Cirujanos , Competencia Clínica , Humanos , Curva de Aprendizaje , Encuestas y Cuestionarios
3.
Tech Coloproctol ; 25(7): 831-839, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33900493

RESUMEN

BACKGROUND: Postoperative ileus is a common condition following abdominal surgery. Previous studies have shown the positive effects of coffee on gastrointestinal motility. The aim of this study was to assess whether caffeine is the stimulatory agent in coffee that triggers bowel motility and thus may reduce the duration of postoperative ileus. METHODS: This was a single-centered, prospective, randomized controlled, double-blinded clinical trial. Patients scheduled to undergo elective laparoscopic colectomy between November 2017 and March 2019 were randomly assigned to receive either oral caffeine (100 mg three times daily) or placebo following the procedure. Primary endpoints were time to first flatus and time to first bowel movement. Secondary endpoints were time to tolerate a solid, low-residue diet and length of hospital stay. Registration number: NCT03097900. RESULTS: Seventy patients were included, [35 males, median age 56 years (range 19-79 years)]. After the exclusion of 12 patients, there were 30 patients in the caffeine group and 28 patients in the placebo group. The first passage of stool in the caffeine group occurred 18 h earlier than in the placebo group (p = 0.012); other endpoints did not reach statistical significance. No caffeine-related adverse events were observed. CONCLUSION: Caffeine consumption following colectomy is safe, leads to a significantly shorter time to first bowel movement, and may thus potentially lead to a shorter postoperative hospital stay.


Asunto(s)
Neoplasias Colorrectales , Ileus , Adulto , Anciano , Cafeína , Motilidad Gastrointestinal , Humanos , Ileus/etiología , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Resultado del Tratamiento , Adulto Joven
4.
Hernia ; 15(3): 321-4, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21259027

RESUMEN

INTRODUCTION: Laparoscopic mesh repair has become an increasingly common method for repairing incisional hernias. The current method for fixating mesh to the abdominal wall includes tacking the mesh to the peritoneum and fascia and suturing the mesh to the fascia with trans-fascial sutures. The iMESH Stitcher™ is a stitching device developed to both simplify and expedite this procedure by passing the suture from one arm of the iMESH stitcher™ to the other. The device enables a stitch to be created in three quick moves using only one hand. We compared both the efficacy and procedure time of trans-fascial mesh fixation when performed with the iMESH stitcher™ as compared to the standard suture passer method. METHODS: A mesh patch was installed on the internal abdominal wall of two pigs. Surgical residents and Medical students were participants in the study and were trained in both techniques. Each participant was asked to perform six fixations with each technique. The procedural time required for both fixation techniques was recorded. Participants were asked to assess subjectively the relative difficulty of each technique on a scale of 1-10 (10 = most difficult). RESULTS: Sixteen residents and students performed a total of 12 mesh fixations, each performing 6 fixations with each technique. Average mesh fixation suture time using the suture passer technique was 44 s for residents and 47 s for students. Average fixation suture time using the iMESH stitcherTM was 17 s for residents and 15 s for students. The average difficulty score for the suture passer technique was 6.1 as compared to 2.9 with iMESH stitcher™. CONCLUSION: Trans-fascial fixation with the iMESH Stitcher™ took significantly less time than the standard suture passer method. The iMESH Stitcher™ significantly simplifies the procedure of transfascial fixation and potentially reduces technical difficulties.


Asunto(s)
Pared Abdominal/cirugía , Laparoscopía/instrumentación , Técnicas de Sutura/instrumentación , Animales , Actitud del Personal de Salud , Eficiencia , Fasciotomía , Hernia Abdominal/cirugía , Humanos , Internado y Residencia , Laparoscopía/métodos , Estudiantes de Medicina , Mallas Quirúrgicas , Porcinos , Estudios de Tiempo y Movimiento
5.
Surg Endosc ; 22(2): 348-51, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18027036

RESUMEN

BACKGROUND: Bowel anastomosis is one of the most challenging and difficult tasks to perform during natural orifice translumenal endoscopic surgery (NOTES). The difficulty is mainly due to the technical limitations of the endoscopic instruments available. Currently, endoscopic clips, T-bar sutures, or cumbersome suturing devices are used. A dual-lumen NOTES approach can facilitate bowel resection in a pig model by allowing the use of laparoscopic staplers through the rectum. METHODS: Acute studies were performed on four 40-kg pig models. The dual-lumen NOTES approach was used to perform small bowel resection and anastomosis. An endoscope was passed into the stomach and pushed through the stomach wall into the peritoneal cavity (first lumen), and a 12-mm trocar was placed through the anterior rectal wall, allowing access to the peritoneum (second lumen). Handling of the bowel, resection, and anastomosis were performed using endoscopic instruments through the gastric lumen and laparoscopic instruments through the rectal lumen. The resected small bowel then was removed through the rectum. RESULTS: Small bowel resection and anastomosis was successfully completed in all four animals using the dual-lumen NOTES approach. The laparoscopic stapler was used one more time to close the gastrotomy through the rectal port. At autopsy, intact suture lines were noted at the bowel anastomosis and at the stomach, with no evidence of leak from either site. CONCLUSIONS: Performing a sutured anastomosis in NOTES is complex and time consuming. The use of stapling devices designed for laparoscopic procedures greatly facilitates gastrointestinal tract operations in NOTES. Using both the upper and lower gastrointestinal tract as entry sites for NOTES eliminates some of the current technical limitations of these procedures.


Asunto(s)
Endoscopía Gastrointestinal/métodos , Intestinos/cirugía , Laparoscopía , Anastomosis Quirúrgica/métodos , Animales , Estudios de Factibilidad , Femenino , Porcinos
6.
World J Surg ; 30(11): 2071-7; discussion 2078-9, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16957818

RESUMEN

BACKGROUND: Terror-related multiple casualty incidents (MCI) in Israel since September 2000 have resulted in a new pattern of injury as a result of the mechanisms of trauma. The objective of this study was to asses the temporal death distribution among the civilian casualties in the Jerusalem vicinity during a 3-year period. METHODS: All terrorist attacks in the Jerusalem district from September 2000 to September 2003 were included in this study. The data of all deaths were processed including the time of the attack, the evacuation time to the hospitals, and the time of death. RESULTS: During the study period 28 terror-related MCI occurred. A total of 2328 victims were injured and 273 died, for an overall fatality rate of 11.7%. A unique temporal death distribution was identified; 82.8% of the deaths occurred immediately, at the scene of the attack (scene death); of the remaining 17.2% of patients who died in the hospital, half died within 4 hours of arrival (immediate death), one quarter within 5-24 hours (early death), and one quarter later than that (late death). The temporal death distribution was significantly different when classifying the mechanism of trauma to suicide bombings versus shooting. The scene mortality was higher in the suicide bombings than in shooting attacks (86.7% versus 77%, P = 0.039 ). In contrast, the mortality within 1-24 hours was higher in the shooting attacks (17% versus 6.3%, P = 0.05). CONCLUSIONS: Terror-related MCI occurring in civilian settings have a unique temporal death distribution. A very high scene mortality is seen compared to the classical description of Donald Trunkey1 in 1983. The late deaths, which composed 30% of the mortality in civilian settings, comprise only 4.4% of the total mortality in MCIs. A rough estimate of the in-hospital mortality could be achieved after the first 4 hours, allowing the assessment and distribution of hospital resources. Futile care should be identified early and availability of ICU beds can be calculated according to the immediate mortality.


Asunto(s)
Mortalidad/tendencias , Terrorismo/estadística & datos numéricos , Humanos , Israel/epidemiología , Factores de Tiempo
7.
Int J Qual Health Care ; 18(2): 123-6, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16234299

RESUMEN

INTRODUCTION: Prevention of venous thromboembolism and coronary events (with beta-blockers) during and after surgery is at the top of a list of safety practices for hospitalized patients, recommended by the Agency for Health Care Research and Quality (AHRQ). We wished to determine and improve adherence to clinical guidelines for these topics in our institution. PATIENTS, MATERIAL, AND METHODS: A prospective survey was conducted over several weeks on operated patients in a 1200-beds medical center (a teaching, community and referral hospital in Jerusalem, Israel). Eligibility for and actual administration of prophylactic treatment with anticoagulant and beta-blockers were determined. Following an intervention program, which included staff meetings, development of local protocols, and academic detailing by a nurse, the survey was repeated. RESULTS: In general, adherence to recommended anticoagulation prophylaxis was low, found in only 29% [95% confidence interval (CI) = 23-36] of eligible patients. After the intervention, adequate anticoagulation increased to 50% (95% CI = 40-59) of eligible patients (P < 0.001). Initiation of beta-blockers in preventing perioperative cardiac events was very low (0%, 95% CI = 0-5%) and did not increase after intervention. CONCLUSIONS: Adherence to guidelines for prevention of surgical complications was found to be low in our institution. A multifaceted intervention significantly increased use of prophylaxis for venous thromboembolism but not for coronary events. This differential response suggests that the success of a quality improvement project strongly depends on topic content and its phase of acceptance.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Hospitales Universitarios/normas , Atención Perioperativa/normas , Complicaciones Posoperatorias/prevención & control , Guías de Práctica Clínica como Asunto , Tromboembolia/prevención & control , Trombosis de la Vena/prevención & control , Adulto , Anciano , Quimioprevención , Adhesión a Directriz/estadística & datos numéricos , Encuestas de Atención de la Salud , Humanos , Israel , Persona de Mediana Edad , Atención Perioperativa/métodos , Estudios Prospectivos , Garantía de la Calidad de Atención de Salud
8.
Surg Endosc ; 18(5): 771-3, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15216859

RESUMEN

BACKGROUND: Soon after its introduction, laparoscopic adrenalectomy (LA) became the procedure of choice in the surgical management of most adrenal tumors. The aim of this study was to assess the outcome and learning curve of the first 100 cases operated by the same surgical team. METHODS: Retrospective analysis of prospectively collected data of 100 consecutive LAs was performed. The parameters studied were indication for surgery, side and length of operation, intra- and postoperative complications, size of tumor, conversion to open surgery, final diagnosis, and length of stay. RESULTS: Between 1996 and 2002, 100 LAs were performed in 90 patients. The procedures included 45 left, 35 right, and 10 bilateral resections for pheochromocytoma (29), Cushings syndrome (27), Conns syndrome (16), nonfunctioning adenoma (13), and others (5). Mean tumor size was 4.16 cm (range, 0.3-11). Overall major morbidity occurred in eight patients (9%); there was one mortality due to cerebrovascular accident in an elderly patient. Five cases (5%) were converted to open surgery. The mean length of stay for the whole group was 4.7 days (range, 2-25). In order to assess the learning curve, procedures were divided into three, equal consecutive groups (n = 33, 33, and 34). Intraoperative complications in the intermediate and late groups were significantly less compared to those in the early group (2/33, 2/34, and 7/33, respectively; (p < 0.05). Similarly, the mean operating time was significantly reduced between the early (169 min) and both intermediate (116 min) and late (127 min) groups (p < 0.005). The conversion rate was reduced between the three groups (3/33, 2/33, and 0/34), but this was not significant (p = 0.06). CONCLUSIONS: As expected, the outcome of LA is associated with a steep learning curve. According to this study, it seems that performance of approximately 30 cases by an experienced laparoscopic surgeon is required to master the procedure.


Asunto(s)
Adrenalectomía , Competencia Clínica , Laparoscopía , Adolescente , Adrenalectomía/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Complicaciones Intraoperatorias , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos
9.
Surg Endosc ; 16(5): 785-8, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11997822

RESUMEN

BACKGROUND: This study reviewed our experience with laparoscopic ventral postoperative (incisional) hernia repair. METHODS: Clinical data from the first 100 cases were analyzed retrospectively. RESULTS: Between 1997 and 2000, 64 women and 36 men (mean age, 58.4 +/- 13.6 years; range, 27-87 years) underwent laparoscopic hernioplasty. Hernias (mean diameter, 6.2 +/- 3.7 cm) were in a midline (74%), subcostal (10%), or other incision location, and were recurrent in 25%, of the patients. The mean operative time was 119 +/- 77 min. Extensive adhesiolysis was necessary in 37 cases. There was no mortality. The recorded complications included inadvertent enterotomies (n = 6), seromas (n = 11), prolonged ileus (n = 4), and prolonged fever (n = 3). Seven cases were converted; to repair accidental enterotomies (n = 4) due to difficult adhesiolysis (n = 2), or to control bleeding (n = 1). Six patients underwent reoperation because of enetric leak (n = 3) or bowel obstruction (n = 3). There were two documented recurrences (2%). The mean follow-up period was 19 months (range, 12-54 months). CONCLUSIONS: Laparoscopic intraperitoneal approach to postoperative ventral (incisional) hernia repair may be associated with significant complications and morbidity, which can be prevented in part by meticulous technique and liberal conversions. The justification of this procedure is the low recurrence rate, according to preliminary results.


Asunto(s)
Hernia Ventral/etiología , Hernia Ventral/cirugía , Laparoscopía/efectos adversos , Laparoscopía/métodos , Peritoneo/cirugía , Politetrafluoroetileno/uso terapéutico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Mallas Quirúrgicas , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Politetrafluoroetileno/efectos adversos , Recurrencia , Reoperación/métodos , Estudios Retrospectivos , Mallas Quirúrgicas/efectos adversos , Insuficiencia del Tratamiento , Resultado del Tratamiento
12.
Surg Laparosc Endosc ; 9(1): 68-9, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9950134

RESUMEN

A 50-year-old woman presented with an adenocarcinoma at a port site of a previous laparoscopic cholecystectomy. A thorough investigation and exploratory laparotomy with excision of the tumor failed to detect its origin.


Asunto(s)
Músculos Abdominales , Adenocarcinoma/secundario , Colecistectomía Laparoscópica/efectos adversos , Neoplasias de los Músculos/secundario , Neoplasias Primarias Desconocidas , Femenino , Humanos , Persona de Mediana Edad , Siembra Neoplásica
13.
Harefuah ; 136(5): 359-61, 419, 1999 Mar 01.
Artículo en Hebreo | MEDLINE | ID: mdl-10914238

RESUMEN

Inguinal hernias are common and have highly variable clinical presentations, ranging from the asymptomatic to surgical emergencies when incarcerated, sometimes necessitating bowel resection. Several techniques have been described for repair of inguinal hernias based on the unique anatomic structure of the inguinal region. In 1989 Lichtenstein and co-workers described a "tension free" repair based on using a synthetic mesh patch to reinforce the inguinal canal floor and as a plug to prevent recurrence through the internal inguinal ring. This technique has been used in many centers worldwide with good rates of success.


Asunto(s)
Hernia Inguinal/cirugía , Polipropilenos , Humanos , Masculino
14.
Arch Orthop Trauma Surg ; 116(6-7): 420-2, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9266055

RESUMEN

Total hip arthroplasty (THA) is one of the major breakthroughs in modern orthopedics this century. Since its introduction in the early 1960s by Sir J. Charnley, it has become the most common form of arthroplasty. The art of performing THA has developed to a large extent, yet with the inevitable "price" of a learning curve. The rates of early and late complications reported in the orthopedic literature have been decreasing gradually, along with improved short- and long-term results. We report the results of two similar series of THA performed with an interval of 15 to 20 years, which show that the improvement of the results that form the learning curve of THA at our institution is statistically significant.


Asunto(s)
Prótesis de Cadera , Anciano , Competencia Clínica , Femenino , Estudios de Seguimiento , Articulación de la Cadera/cirugía , Humanos , Complicaciones Intraoperatorias , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Falla de Prótesis
15.
J Bacteriol ; 175(5): 1375-83, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8444800

RESUMEN

The Escherichia coli F plasmid gene required for amino-terminal acetylation of F-pilin subunits was identified. Using Western blots (immunoblots), we assayed the reaction of monoclonal antibodies with F-pilin polypeptides in inner membrane preparations from various F mutant strains. It was known that JEL92 recognizes an internal pilin epitope and JEL93 recognizes the acetylated amino-terminal sequence (L.S. Frost, J.S. Lee, D.G. Scraba, and W. Paranchych, J. Bacteriol. 168:192-198, 1986). As expected, neither antibody reacted with inner membranes from F- cells or Flac derivatives that do not synthesize pilin. Mutations that affected the individual activities of F tra genes traA, -B, -C, -D, -E, -F, -G, -H, -I, -J, -K, -L, -M, -N, -P, -R, -U, -V and -W or trb genes trbA, -B, -C, -D, -E, -G, -H, and -I did not prevent JEL92 or JEL93 recognition of membrane pilin. However, Hfr deletion mutants that lacked the most-distal transfer region genes did not express pilin that reacted with JEL93. Nevertheless, all strains that retained traA and traQ did express JEL92-reactive pilin polypeptides. Analysis of strains expressing cloned tra segments showed that traA and traQ suffice for synthesis of JEL92-reactive pilin, but synthesis of JEL93-reactive pilin is additionally dependent on traX. We concluded that the traX product is required for acetylation of F pilin. Interestingly, our data also showed that TraA+ TraQ+ cells synthesize two forms of pilin which migrate at approximately 7 and 8 kDa. In TraX+ cells, both become acetylated and react with JEL93. Preparations of wild-type F-pilus filaments contain both types of subunits.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas de Escherichia coli , Escherichia coli/genética , Factor F , Acetilación , Anticuerpos Monoclonales , Proteínas de la Membrana Bacteriana Externa/genética , Western Blotting , Proteínas Fimbrias , Genes Bacterianos , Mutación
16.
Science ; 215(4539): 1498-501, 1982 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-17788673

RESUMEN

Calculations with a numerical model of the atmosphere show that the global fields of rainfall, temperature, and motion strongly depend on the land- surface evapotranspiration. This confirms the long-held idea that the surface vegetation, which produces the evapotransporation, is an important factor in the earth's climate.

18.
Biochim Biophys Acta ; 544(2): 273-83, 1978 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-152657

RESUMEN

Heparin was found to be the most potent inhibitor of rat ovarian luteinizing hormone-sensitive adenylate cyclase (I50 = 2 microgram/ml) when compared to other naturally occurring glycosamin oglycans. This inhibition was also apparent when this enzyme was stimulated by follicle-stimulating hormone or prostaglandin E2. Heparin was also found to inhibit glucagon-sensitive rat hepatic adenylate cyclase, and the prostaglandin E1-sensitive enzyme from rat ileum and human platelets. In contrast, heparin stimulated the dopamine sensitive adenylate cyclase from rat caudate nucleus. The sulfated polysugar dextran sulfate exerts similar effects on adenylate cyclase activity of the rat ovary and was shown to inhibit hormone binding to rat ovarian plasma membrane in a manner similar to that exerted by heparin. In contrast to heparin, dextran sulfate inhibited dopamine-sensitive adenylate cyclase from rat caudate nucleus.


Asunto(s)
Adenilil Ciclasas/metabolismo , Dextranos/farmacología , Glicosaminoglicanos/farmacología , Animales , Plaquetas/enzimología , Núcleo Caudado/enzimología , Membrana Celular/enzimología , Gonadotropina Coriónica/farmacología , Femenino , Hormona Folículo Estimulante/farmacología , Humanos , Íleon/enzimología , Mucosa Intestinal/enzimología , Cinética , Hígado/enzimología , Hormona Luteinizante/farmacología , Masculino , Ovario/enzimología , Prostaglandinas E/farmacología , Ratas
20.
J Cyclic Nucleotide Res ; 3(3): 163-76, 1977 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-198442

RESUMEN

A concomitant increase in the activity of LH-senstive adenylate cyclase and in the number of LH/hCG binding sites was induced in ovaries of immature rats upon administration of pregnant mare serum gonadotropin (PMSG), a hormone preparation known to have predominantly follicle stimulation (FSH-like) activity. When an optimal dose of PMSG (15 i.u./rat) was administered to 25-day-old rats, specific activity of LH-dependent adenylate cyclase and the number of binding sites for LH/hCG per mg protein remained unchanged during the first 24h, but 48h after injection a 2-to 4-fold increase in both parameters was observed. By contrast, there was no change in basal adenylate cyclase activity or in the response of the enzyme to the stimulatory action of guanosine-5'-(beta gamma-imino) triphosphate (Gpp (NH)p), GTP, or NaF. Specific activity of succinate cytochrome c reductase, glucose-6-phosphatase and 5'-nucleotidase were found to be unaffected by the hormonal pretreatment, although total protein determined in these homogenates increased 3-fold in the course of this treatment. It is inferred that during follicular maturation, FSH enhances the responsiveness of ovarian adenylate cyclase to LH by stimulating the insertion of LH/hCG-receptors into the cell membrane.


Asunto(s)
Adenilil Ciclasas/metabolismo , Gonadotropina Coriónica/metabolismo , Gonadotropinas Equinas/farmacología , Hormona Luteinizante/farmacología , Ovario/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Femenino , Glucosa-6-Fosfatasa/metabolismo , Guanosina Trifosfato/farmacología , Nucleotidasas/metabolismo , Ratas , Receptores de Superficie Celular/metabolismo , Succinato Citocromo c Oxidorreductasa/metabolismo
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