[Acute renal failure of the donor in encephalic death: A real contraindication to kidney transplantation?] / L'insuffisance rénale aiguë du donneur en mort encéphalique : une réelle contre-indication à la transplantation rénale ?

INTRODUCTION: The shortage of kidney transplants encourages the expansion of the limits of eligibility criteria for donation. Many donors who are brain dead display acute renal failure at the time of death; is this a real contraindication to harvesting? The aim of this study was to assess kidney graft survival from donors after brain death with confirmed acute renal failure, with or without anuria previous donation. MATERIALS AND METHODS: All of the transplants performed in two university hospitals between 2010 and 2017 were analyzed retrospectively. All patients who underwent single kidney transplant from a brain-dead donor with acute renal failure (ARF) were included in this study. ARI was defined here by a decrease over 50 % of glomerular filtration rate (GFR) to a threshold below 45mL/min/1.73 m2 at the time of kidney procurement. Kidney graft survival, incidence of delayed graft function (DGF) and the GFR at 12 months were analyzed. Analysis of kidney transplant survival based on pre-implantation biopsies was additionally done. RESULTS: One hundred and sixty four patients were transplanted with a kidney from donor with ARF during the selected period. At the admission in ICU the average GFR was 67,7±19mL/min/1,73m2. At the time of donation, the average age of donors was 56.4±17.7 years, the GFR was 33.7±8.0mL/min/1.73 m2 16 % of donors were anuric. Cold ischemia time (CIT) was 16.8±5.0hours. The average age of recipients was 55.6±14.1 years. 81 % of the cases were primary transplants. Graft function took place within 7.8±9.4 days after transplantation. There were two non-primary functions (PNF). One hundred and fifty two patients (93 %) had a functional graft at 12 months. The mean GFR at 12 months was 46.8±20.1mL/min/1.73 m2 and 122 patients (73 %) had a GFR greater than 30mL/min/1.73 m2. Seventy-one percent of preimplantation biopsies revealed acute tubular necrosis (ATU); no cortical necrosis was observed. Survival of theses grafts was 85 %, comparable to the total population of study (P=0,21) CONCLUSION: The acute renal failure of the brain-dead donor should not alone be systematically a contraindication to harvesting and kidney transplantation.

[Renal cell carcinoma in candidates for renal transplantation and recipients of a kidney transplant: The French guidelines from CTAFU]. / Recommandations françaises du Comité de transplantation de l'association française d'urologie (CTAFU) : carcinome rénal sur reins natifs chez le patient transplanté rénal ou en attente de transplantation.

OBJECTIVE: To define guidelines for the management of renal cell carcinoma of the native kidney (NKRCC) in kidney transplant (KTx) recipients and renal cell carcinoma (RCC) in end-stage renal disease (ESRD) patients candidates for renal transplantation. METHOD: A review of the literature following a systematic approach (Medline) was conducted by the CTAFU to report renal cell carcinoma epidemiology, screening, diagnosis and management in KTx candidates and recipients. References were assessed according to a predefined process to propose recommendations with the corresponding levels of evidence. RESULTS: ESRD patients are at higher risk of RCC with a standardized incidence ratio of approximately 4,5 as compared with general population. NKRCC tumors occur in 1 to 3 % of KTx recipients with a 10 to 15-fold increased risk as compared with general population, especially in patients with acquired multicystic kidney disease. Most authors suggest yearly monitoring of the native kidneys using ultrasound imaging. Radical nephrectomy (either open or laparoscopic approach) is the preferred treatment of NKRCC in KTx recipients and RCC in ESRD. Surveillance in a valid option in small or cystic renal masses. In the localized setting, change in immunosuppressive therapy is not recommended besides perioperative avoidance of mTOR inhibitor to limit morbidity. CTAFU does not recommend a mandatory waiting time after nephrectomy for RCC in ESRD patients candidates for renal tranplantation when tumor stage

[Urothelial carcinoma in kidney transplant recipients and candidates: The French guidelines from CTAFU]. / Recommandations françaises du Comité de transplantation de l'association française d'urologie (CTAFU) : carcinome urothélial chez le patient transplanté rénal et le candidat à la transplantation rénale.

OBJECTIVE: To propose surgical recommendations for urothelial carcinoma management in kidney transplant recipients and candidates. METHOD: A review of the literature (Medline) following a systematic approcah was conducted by the CTAFU regarding the epidemiology, screening, diagnosis and treatment of urothelial carcinoma in kidney transplant recipients and candidates for renal transplantation. References were assessed according to a predefined process to propose recommendations with levels of evidence. RESULTS: Urothelial carcinomas occur in the renal transplant recipient population with a 3-fold increased incidence as compared with general population. While major risk factors for urothelial carcinomas are similar to those in the general population, aristolochic acid nephropathy and BK virus infection are more frequent risk factors in renal transplant recipients. As compared with general population, NMIBC in the renal transplant recipients are associated with earlier and higher recurrence rate. The safety and efficacy of adjuvant intravesical therapies have been reported in retrospective series. Treatment for localized MIBC in renal transplant recipients is based on radical cystectomy. In the candidate for a kidney transplant with a history of urothelial tumor, it is imperative to perform follow-up cystoscopies according to the recommended frequency, depending on the risk of recurrence and progression of NMIBC and to maintain this follow-up at least every six months up to transplantation whatever the level of risk of recurrence and progression. Based on current data, the present recommendations propose guidelines for waiting period before active wait-listing renal transplant candidates with a history of urothelial carcinoma. CONCLUSION: The french recommendations from CTAFU should contribute to improve the management of urothelial carcinoma in renal transplant patients and renal transplant candidates by integrating both oncologic objectives and access to transplantation.

Robot-assisted renal transplantation using the retroperitoneal approach (RART) with more than one year follow up: Description of the technique and results.

OBJECTIVES: To describe the technique and report our first experience of robotic-assisted renal transplantation (RART) with more than one year follow up. PATIENTS AND METHODS: In our center the first case of RART was realized in October 2013 with a cadaveric graft. We used the combined extra- and intraperitoneal robot assisted laparoscopic route with extraperitoneal positioning of the graft and intraperitoneal transplantation. The patient was placed in the supine position with arms along the body; the robot came from the right inferior part of the patient. Access to the retroperitoneal space was obtained using an Alexis trocar that permitted the insertion of the kidney with ice without losing the pneumoperitoneum. Ports included a 12-mm camera port (placed under the ombilicus), two 8-mm robotic ports (placed 6cms laterally from the previous port) and a 12-mm assistant port (placed between the upper port and the ombilic). All the pre-, per- and postoperative data were prospectively included in a database. We report the results of the initial experience of RART, performed with more than one year follow-up. RESULTS: This technique is the first described using the retroperitoneal approach that is the routine approach for conventional open renal transplantation. This approach permitted to perform excellent arterial, veinous and ureteral anastomosis. Eight cases of RART were conducted between October 2013 and November 2015 (five men and three women). The average age was 58 years (range 39-75years). The average body mass index was 28 (range 22-38). Five patients had history of abdominal surgery and were dialyzed for 30 months on average (range 3-63months). Three left and five right cadavers kidneys were transplanted in the right iliac fossa. The mean graft size was 109mm (range 90-130). The mean length of the incision for insertion of the graft was 60 mms (40-100mms). Mean warm ischemia time was 63minutes (range 46-84). The total operative time was 200minutes (149-245). No patient was transfused during surgery and two were transfused postoperatively. Median length of hospital stay was 14 days (range 10-30 days). Only one patient needed postoperative morphine, the pain visual analogic scale 12hours postoperatively was 2 (0-5). Mean serum creatinine at seven days, at three months and at one year was 400 (98-639micromol/L), 151 (80-235micromol/L) and 129 (86-194micromol/L) respectively. At one year follow-up, no patient had a wound infection or incisional hernia. One patient was re-operated for ureteral anastomosis stricture. CONCLUSION: The retroperitoneal approach for RART permits the kidney to be cooled and a direct access to the iliac vessels and bladder. This initial series with more than a year of post-monitoring RART shows promising results despite some initial technical difficulties. The procedure can still be improved and hoped to see an improvement in the results. A comparison to the results of the conventional route is necessary before diffusing the robot-assisted technique. LEVEL OF PROOF: 3.

[Impact of learning curve in renal transplantation]. / Impact de la courbe d'apprentissage dans la transplantation rénale.

OBJECTIVES: Renal transplantation is performed only in university hospital centres, in accredited transplanting centres. The aim of this study is to analyse the learning curve of this operation and its impact on the graft survival. PATIENTS-METHODS: Monocentric retrospective study in which 3 groups have been defined: Juniors 1, Juniors 2 and Seniors corresponding respectively to the first thirty transplantations and to the last thirty transplantations of 5 clinical leaders, and 30 transplantation graft of referent seniors. Data have been registered in a database. Operation times, lukewarm ischemic times and postoperative complications have been compared within the 3 groups. RESULTS: A clear difference of operation time has been noted within the 3 groups with an average time of 202 minutes for Juniors 1, 173 minutes for Juniors 2 and 140 minutes for Seniors (P<0.0001). Likewise, concerning lukewarm ischemic time and vascular anastomosis time respectively with an average time of 72, 59 and 40 min (P<0.0001). Vascular complications occurred in 20% of cases in Juniors 1, 44.3% of cases in Juniors 2 and 17% of cases in Seniors (P=0.65). There were no significant differences of survival without urinary complications: 20% of complications for Juniors 1, 10% for Juniors 2 and 17% for Seniors (P=0.63). Similarly results have been obtained with analysing complications following Clavien's order. CONCLUSION: This study reveals that renal transplantations operated by young surgeons require longer operation and lukeward ischemic time but without significant repercussions on the surgical complication rate and the global survival. This stresses on the importance of surgical training during medicine internship.

De novo kidney graft tumors: results from a multicentric retrospective national study.

De novo tumors in renal allografts are rare and their prevalence is underestimated. We therefore analyzed renal cell carcinomas arising in renal allografts through a retrospective French renal transplant cohort. We performed a retrospective, multicentric survey by sending questionnaires to all French kidney transplantation centers. All graft tumors diagnosed after transplantation were considered as de novo tumors. Thirty-two centers participated in this study. Seventy-nine tumors were identified among 41 806 recipients (Incidence 0.19%). Patients were 54 men and 25 women with a mean age of 47 years old at the time of diagnosis. Mean tumor size was 27.8 mm. Seventy-four (93.6%), 53 (67%) and 44 tumors (55.6%) were organ confined (T1-2), low grade (G1-2) and papillary carcinomas, respectively. Four patients died of renal cell carcinomas (5%). The mean time lapse between transplantation and RCC diagnosis was 131.7 months. Thirty-five patients underwent conservative surgery by partial nephrectomy (n = 35, 44.3%) or radiofrequency (n = 5; 6.3%). The estimated 5 years cancer specific survival rate was 94%. Most of these tumors were small and incidental. Most tumors were papillary carcinoma, low stage and low grade carcinomas. Conservative treatment has been preferred each time it was feasible in order to avoid a return to dialysis.

[Kidney transplantation in obese recipients: review of the Transplantation Committee of the French Association of Urology]. / Transplantation rénale et receveurs obèses : revue du comité de transplantation de l'Association française d'urologie.

INTRODUCTION: Transplantation Committee of the French Association of Urology (CTAFU) conducted a review of the complication of kidney transplantation in obese recipients. MATERIAL AND METHODS: A bibliographic research in French and English using Medline with the keywords "obesity", "body mass index", "kidney transplantation", "graft function", "survival", "wound complications", "graft rejection" and "graft survival" was performed. We limited the review for the last fifteen years because of the change in immunosuppressive treatment area. Only studies with more than 20 obese patients were selected. RESULTS: Wound or infectious postoperative complications and delayed graft function are more frequent in obese patients than in non-obese recipients. Similarly, transplant survival at 5 years is lower in obese patients. On the other hand, patient survival and acute rejection are the same between the two groups if recipient selection is carefully made, particularly with regard to heart complication. CONCLUSION: Kidney transplantation in obese patients is not an easy surgery with known complication. Obese patients will take time before transplantation to explain all the risk and a regular heart follow-up is crucial if we don't want to reduce patient survival. But obese survival is better if we proceed to kidney transplantation than if they stay on dialysis, arguing for a non-exclusion of the waiting list. So there is the need for a national study concerning obese patients on waiting list to enact future guidelines.

[Pelvic lymphadenectomy in prostate cancer: Should it be realized by laparoscopy?]. / Le curage ilio-obturateur dans le cancer de la prostate doit-il être réalisé par voie coelioscopique ?

AIM: Laparoscopic pelvic lymphadenectomy in localized prostatic cancer is performed since the 1990s, lessens the postoperative complications and respects carcinologic's principles (No. lymph nodes removed and lymph nodes metastasis). In order to verify that these objectives are achieved, we compared our results of pelvic lymphadenectomy by laparotomy and by laparoscopy for the past 12 years. PATIENTS AND METHODS: Between January 1997 and June 2008, 36 (23.8%) patients underwent open pelvic lymphadenectomy and 76.16% (115 cases) laparoscopic pelvic lymphadenectomy. We did a retrospective and comparative analysis of data including the preoperative characteristics, per- and postoperative complication as well pathologic results. RESULTS: Preoperative data were comparable between both groups. The comparison of the peroperative data showed an increased bleeding volume in the open group (105.6±420.9mL; 12.1±96.1mL: P=0.001) and longer operative time in the laparoscopic group (103.7±83.9min; 132.8±40.9min: P=0.006). Postoperative complications were similar. Pathologic results showed a significantly more important number of lymph nodes removed in the open group (7.2±3.5; 5.7±3.2: P=0.022), but the positive rate similar in both groups (13.9%; 22.6%: P=0.258). In order to remove "the learning curve effect", we compared 36 open pelvic lymphadenectomy to the last 36 laparoscopic pelvic lymphadenectomy. In the laparoscopic group the patients showed an upper Gleason score (6.3±1.1; 7±1: P=0.005); but there was no difference for the operative time, number of lymph nodes removed and the complications rates. CONCLUSIONS: After training, laparoscopic pelvic lymphadenectomy was similar to open pelvic lymphadenectomy.

[Ureteral stenosis after renal transplantation: Risk factors and impact on survival]. / Sténoses urétérales après transplantation rénale : facteurs de risque et impact sur la survie.

OBJECTIVES: To identify the risk factors for ureteral stenosis after renal transplantation and to evaluate their impact on both graft and patient survival. PATIENTS AND METHODS: This retrospective study included 789 kidney transplants among 782 patients performed at our institution between 1995 and 2007. The parameters studied included the characteristics of the donor, recipient and transplant, the surgical variables, the elements of the monitoring process and a graft and patient survival. RESULTS: The ureteral stenosis rate after renal transplantation was found to be 6.5%, and the ureterovesical junction was the most common location (68%). A univariate analysis showed that this complication was significantly associated with a higher donor age (P=0.01), abnormal graft revascularisation (P=0.032) and DGF (Delay Graft Function) (P=0.05). In multivariate analysis, only donor age (P=0.001) and abnormal graft revascularisation (P=0.035) were independent risk factors for ureteral stenosis after renal transplantation. When ureteral stenosis was treated, an analysis of the survival curves according to the Kaplan-Meier method did not reveal significant differences either in graft survival (P=0.518) or overall survival of the patients (P=0.614) as compared to the control group. CONCLUSIONS: In the present study, donor age and abnormal graft revascularisation were independent risk factors for ureteral stenosis after renal transplantation. This result is a strong argument for an ischemic component in the genesis of ureteral stenosis after renal transplantation, which should help to identify patients at risk.

Is urine culture routinely necessary before prostate biopsy?

The objective of this study was to assess the value of a urine bacterial culture performed before prostate biopsy. We performed a prospective study on 353 patients who underwent prostate biopsy. All patients had a urine bacterial culture performed before biopsy. We compared the outcomes of patients with bacteriuria (left untreated) with those of patients without bacteriuria. Of the 353 men, 12 had a pre-biopsy-positive bacterial culture and underwent prostate biopsy without any infectious complication. Fifteen patients with a negative pre-biopsy culture developed a post-biopsy-positive bacterial culture, but remained asymptomatic without any treatment. Only four men from the group without pre-biopsy bacteriuria developed an infectious complication, requiring 3 weeks of antibiotic therapy. The complication rates were similar for both groups. Our results suggest that routine urine bacterial culture before prostate biopsy is not useful when antibiotic prophylaxis and enema are performed. We do, however, suggest performing a urine bacterial culture before prostate biopsy for patients with a previous history of urinary tract infections.

[Management of perianastomotic stenoses complicating vascular accesses for haemodialysis]. / Prise en charge des sténoses périanastomotiques compliquant les abords vasculaires pour hémodialyse.

OBJECTIVE: Perianastomotic stenoses (PAS) complicating native arteriovenous fistulas (AVF) of the forearm can be treated by angioplasty or surgery. The objective of this study was to report primary patency (PP) and primary assisted patency (PAP) rates of surgery and angioplasty of these stenoses. The secondary objective was to identify factors influencing the patency rates of these reoperations. MATERIAL AND METHODS: Seventy-three patients with a mean age, 65 years were treated for PAS between January 1999 and December 2005 in two centres (Tours and Le Mans), which were retrospectively included. PAS were treated by surgery (n=21) or angioplasty (n=52). The two groups were comparable. The mean follow-up was 39 months for the angioplasty group and 49 months for the surgery group (p=0.088). RESULTS: The PP rate was 71+/-10% for surgery and 41+/-6% for angioplasty (p<0.0175). The PAP rate was not significantly different (p=0.462) between angioplasty (92+/-4%) and surgery (95+/-4%). In the endovascular group, the site of stenosis on the anastomosis was a risk factor for early recurrence (95% CI between 0.006 and 0.392; p=0.047). CONCLUSION: These results suggest that anastomotic stenoses should be treated surgically rather than by angioplasty. Angioplasty and surgery give identical patency rates in other types of perianastomotic stenoses at the cost of a higher reoperation rate for angioplasty.

Prevalence and risk factors of urinary incontinence in young and middle-aged women.

Objective To assess the prevalence of and risk factors for urinary incontinence (UI) in young and middle-aged women. Subjects and methods During 1998 the prevalence of overall, stress, urge and mixed UI was assessed in women working in a French academic hospital. Women (2800) received a questionnaire at the same time as their yearly interview with a staff physician in occupational medicine. The usual risk factors for constitutional events, i.e. increasing age, obesity (defined as a body mass index of > or = 25), obstetric events (pregnancy, previous Caesarean delivery, previous vaginal delivery, postpartum incontinence) and gynaecological events (hysterectomy) were evaluated. Results Of the 1700 women (mean age 40.0 years) who returned the questionnaire, 467 (27.5%, 95% confidence interval, CI, 25.4-29.7) reported UI, comprising 210 (12.4%, 10.8-14.0) with stress UI, 28 (1.6%, 1.1-2.4) with urge UI and 229 (13.5%, 11.9-15.2) with mixed UI. Thirty-eight women (8.1%) had frequent urinary leakage, comprising one (0.5%), four (14.3%) and 33 (14.4%) with stress, urge and mixed UI. The prevalence of UI increased significantly with age > or = 40 years, with a relative risk (95% CI) of 2.16 (1.86-2.57), and with pregnancy (2.22, 1.71-2.87), previous vaginal delivery (2.15, 1.72-2.69), postpartum incontinence (2.57, 2.22-2.97), and hysterectomy (1.52, 1.11-2.08). Obesity (1.14, 0.99-1.32) and previous Caesarean delivery (2.15, 1.72-2.69) did not significantly increase the risk of UI. The risk factors for stress UI were age > or = 40 years, pregnancy, previous vaginal delivery, postpartum incontinence and hysterectomy, but there was no relationship between stress UI and obesity or previous Caesarean delivery. Conclusion There was a high prevalence of UI among young adult and middle-aged women hospital workers who had easy access to medical resources. Gynaecological and obstetric events (pregnancy, particularly previous vaginal delivery and hysterectomy) were the most prominent risk factors, especially for stress UI.

Aberrant membrane hormone receptors in incidentally discovered bilateral macronodular adrenal hyperplasia with subclinical Cushing's syndrome.

Cortisol secretion in adrenal Cushing's syndrome can be regulated by the aberrant adrenal expression of receptors for gastric inhibitory polypeptide, vasopressin, catecholamines, LH/human CG (LH/hCG), or serotonin. Four patients with incidentally discovered bilateral macronodular adrenal hyperplasia without clinical Cushing's syndrome were evaluated for the possible presence of aberrant adrenocortical hormone receptors. Urinary free cortisol levels were within normal limits, but plasma cortisol levels were slightly elevated at nighttime and suppressed incompletely after dexamethasone administration. Plasma ACTH was partially suppressed basally but increased after administration of ovine CRH. A 51-yr-old woman had ACTH-independent increases of plasma cortisol after 10 IU AVP im (292%), 100 microg GnRH iv (184%), or 10 mg cisapride orally (310%); cortisol also increased after administration of NaCl (3%), hCG, human LH, and metoclopramide. In a 61-yr-old man, cortisol was increased by AVP (349%), GnRH (155%), hCG (252%), and metoclopramide (191%). Another 53-yr-old male increased plasma cortisol after AVP (171%) and cisapride (142%). Cortisol secretion was also stimulated by vasopressin in a 54-yr-old female. This study demonstrates that subclinical secretion of cortisol can be regulated via the aberrant function of at least V1-vasopressin, LH/hCG, or 5-HT4 receptors in incidentally identified bilateral macronodular adrenal hyperplasia.

Intestinal perforation as a complication of tension-free vaginal tape procedure for urinary incontinence.

OBJECTIVES: To report and prevent a serious complication of tension-free vaginal tape (TVT) procedure. CASE REPORT: One day after a TVT procedure, an emergency CT scan showed adhesion of intestinal loops with a pneumoperitoneum. The patient had previously had intra- and retroperitoneal surgery with a sacral cervicopexy and a Burch colposuspension. CONCLUSION: In such a case of previous surgery, a CT scan may be useful before a TVT procedure.

Identification of nuclear orphan receptors as regulators of expression of a neurotransmitter receptor gene.

Nuclear orphan receptors are known to be important mediators of neurogenesis, but the target genes of these transcription factors in the vertebrate nervous system remain largely undefined. We have previously shown that a 500-base pair fragment in the first intron of the GRIK5 gene, which encodes the kainate-preferring glutamate receptor subunit KA2, down-regulates gene expression. In our present studies, mutation of an 11-base pair element within this fragment resulted in a loss of nuclear protein binding and reverses negative regulation by the intron. Using yeast one-hybrid screening, we have identified intron-binding proteins from rat brain as COUP-TFI, EAR2, and NURR1. Gel shift studies with postnatal day 2 rat brain extract indicate the presence of COUP-TFs, EAR2, and NURR1 in the DNA-protein complex. Competition assays with GRIK5-binding site mutations show that the recombinant clones exhibit differential binding characteristics and suggest that the DNA-protein complex from postnatal day 2 rat brain may consist primarily of EAR2. The DNA binding activity was also observed to be enriched in rat neural tissue and developmentally regulated. Co-transfection assays showed that recombinant nuclear orphan receptors function as transcriptional repressors in both CV1 cells and rat CG4 oligodendrocyte cells. Direct interaction of the orphan receptors with and relief of repression by TFIIB indicate likely role(s) in active and/or transrepression. Our findings are thus consistent with the notion that multiple nuclear orphan receptors can regulate the transcription of a widely expressed neurotransmitter receptor gene by binding a common element in an intron and directly modulating the activity of the transcription machinery.

Asynchronous development of bilateral nodular adrenal hyperplasia in gastric inhibitory polypeptide-dependent cushing's syndrome.

Gastric inhibitory polypeptide (GIP)-dependent Cushing's syndrome has been reported to occur either in unilateral adrenal adenoma or in bilateral macronodular adrenal hyperplasia. A 33-yr-old woman with Cushing's syndrome was found to have two 2.5- to 3-cm nodules in the right adrenal on computed tomography scan; the left adrenal appeared normal except for the presence of a small 0.8 x 0.6-cm nodule. Uptake of iodocholesterol was limited to the right adrenal. Plasma morning cortisol was 279 nmol/L fasting and 991 nmol/L postprandially, and ACTH remained suppressed. Plasma cortisol increased after oral glucose (202%) or a lipid-rich meal (183%), but not after a protein-rich meal (95%) or iv glucose (93%); the response to oral glucose was blunted by pretreatment with 100 microg octreotide, sc. Plasma cortisol and GIP levels were positively correlated (r = 0.95; P = 0.0001); cortisol was stimulated by the administration of human GIP iv (225%), but not by GLP-1, insulin, TRH, GnRH, glucagon, arginine vasopressin, upright posture, or cisapride orally. A right adrenalectomy was performed; GIP receptor messenger ribonucleic acid was overexpressed in both adrenal nodules and in the adjacent cortex. Histopathology revealed diffuse macronodular adrenal hyperplasia without internodular atrophy. Three months after surgery, fasting plasma ACTH and cortisol were suppressed, but cortisol increased 3.6-fold after oral glucose, whereas ACTH remained suppressed; this was inhibited by octreotide pretreatment, suggesting that cortisol secretion by the left adrenal is also GIP dependent. We conclude that GIP-dependent nodular hyperplasia can progress in an asynchronous manner and that GIPR overexpression is an early event in this syndrome.

Autoregulation of the rat prolactin gene in lactotrophs.

The autoregulation of prolactin (PRL) secretion in the rat has been demonstrated at both the hypothalamus and the pituitary levels. Studies on the direct negative feedback effect of PRL in the lactotrophs have concentrated on the acute effect on PRL secretion which does not involve change in PRL synthesis. In this study, we have developed a cotransfection assay in somatolactotrophs where we examine the effect of PRL on the transcription of its own gene. We found that oPRL, at physiological concentrations, exerts a strong and specific inhibition of the rPRL gene transcription in PRL-deficient GC cells. This effect is mediated by both the intermediate and the long forms of PRL receptor. The inhibition was also reproduced in GH3 cells, which secretes PRL, by adding exogenous oPRL in the presence of anti-rat PRL antiserum to neutralize endogenous rPRL. Cellular specificity was demonstrated by testing this regulation in non-pituitary cell types where no modulation of the PRL promoter reporter gene could be elicited by PRL, even with cotransfection with the Pit-1 expression vector. Finally, deletions of the rPRL promoter indicate that the full inhibitory effect of PRL requires the same regulatory domains (proximal and distal) that have been described for the other PRL gene regulators. These results strongly suggest the existence of the extra-short loop regulation of the rat PRL at the transcriptional level.

Nuclear orphan receptors COUP-TFII and Ear-2: presence in oxytocin-producing uterine cells and functional interaction with the oxytocin gene promoter.

We have previously demonstrated that the oxytocin (OT) gene is expressed in the rat uterine epithelium and that its expression is upregulated in vivo and in vitro by estrogen. This hormonal regulation is mediated by a hormone response element (HRE) located in the OT gene promoter. Here we show that the same OT-HRE is also capable of interacting with two novel members of the orphan nuclear receptor family, rat COUP-TFII and Ear-2, and that this interaction antagonizes the estrogenic induction of the OT promoter. By Northern blot analysis and immunocytochemistry, using specific cDNA probes and antibodies, respectively, we demonstrate furthermore that both orphan receptors are expressed in uterine epithelial cells. Therefore, the present findings indicate that uterine OT gene expression is under stimulatory as well as inhibitory influences which are both mediated by the same HRE. More detailed analysis of the sequences necessary for estrogen receptor action and for orphan receptor action, using site-directed mutagenesis, revealed that the specific recognition sequences are overlapping but distinct: whereas the (imperfect) palindromic structure of the HRE constitutes the estrogen response element (ERE), orphan receptor action relies on an underlying direct TGACC repeat which forms part of the OT-HRE structure and overlaps with the estrogen response element.

Cellular expression of growth hormone and prolactin receptors in human breast disorders.

Growth hormone (GH) and prolactin (PRL) exert their regulatory functions in the mammary gland by acting on specific receptors. Using isotopic in situ hybridization and immunohistochemistry, we have localized the expression of hGH receptor (hGHR) and hPRL receptor (hPRLR) in a panel of human breast disorders. Surgical specimens from adult females included normal breast, inflammatory lesions (mastitis) benign proliferative breast disease (fibroadenoma, papilloma, adenosis, epitheliosis), intraductal carcinoma or lobular carcinoma in situ, and invasive ductal, lobular or medullary carcinoma. Cases of male breast enlargement (gynecomastia) were also studied. In situ hybridization analysis demonstrated the co-expression of hGHR and hPRLR mRNA in all samples tested. Epithelial cells of both normal and tumor tissues were labelled. Quantitative estimation of receptor mRNA levels was regionally measured in areas corresponding to tumor cells and adipose cells from the same section. It demonstrated large individual variation and no correlation emerged according to the histological type of lesion. Receptor immunoreactivity was detected both in the cytoplasm and nuclei or in the cytoplasm alone. Scattered stromal cells were found positive in some cases, but the labeling intensity was always weaker than for neoplastic epithelial cells. Our results demonstrate the expression of the hGHR and hPRLR genes and their translation in epithelial cells of normal, proliferative and neoplastic lesions of the breast. They also demonstrate that stromal components express GHR and PRLR genes. Thus the putative role of hGH or hPRL in the progression of proliferative mammary disorders is not due to grossly altered levels of receptor expression.