Unmet needs and perspectives in rheumatoid arthritis-associated interstitial lung disease: A critical review

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by synovitis as the most common clinical manifestation, and interstitial lung disease (RA-ILD) represents one of the most common and potentially severe extra-articular features. Our current understanding of the mechanisms and predictors of RA-ILD is limited despite the demonstration that an early identification of progressive fibrosing forms is crucial to provide timely treatment with antifibrotic therapies. While high resolution computed tomography is the gold standard technique for the diagnosis and follow-up of RA-ILD, it has been hypothesized that serum biomarkers (including novel and rare autoantibodies), new imaging techniques such as ultrasound of the lung, or the application of innovative radiologic algorithms may help towards predicting and detecting early forms of diseases. Further, while new treatments are becoming available for idiopathic and connective tissue disease-associated forms of lung fibrosis, the treatment of RA-ILD remains anecdotal and largely unexplored. We are convinced that a better understanding of the mechanisms connecting RA with ILD in a subgroup of patients as well as the creation of adequate diagnostic pathways will be mandatory steps for a more effective management of this clinically challenging entity.

The Development of an Intelligent Agent to Detect and Non-Invasively Characterize Lung Lesions on CT Scans: Ready for the "Real World"?

(1) Background: Once lung lesions are identified on CT scans, they must be characterized by assessing the risk of malignancy. Despite the promising performance of computer-aided systems, some limitations related to the study design and technical issues undermine these tools' efficiency; an "intelligent agent" to detect and non-invasively characterize lung lesions on CT scans is proposed. (2) Methods: Two main modules tackled the detection of lung nodules on CT scans and the diagnosis of each nodule into benign and malignant categories. Computer-aided detection (CADe) and computer aided-diagnosis (CADx) modules relied on deep learning techniques such as Retina U-Net and the convolutional neural network; (3) Results: Tests were conducted on one publicly available dataset and two local datasets featuring CT scans acquired with different devices to reveal deep learning performances in "real-world" clinical scenarios. The CADe module reached an accuracy rate of 78%, while the CADx's accuracy, specificity, and sensitivity stand at 80%, 73%, and 85.7%, respectively; (4) Conclusions: Two different deep learning techniques have been adapted for CADe and CADx purposes in both publicly available and private CT scan datasets. Experiments have shown adequate performance in both detection and diagnosis tasks. Nevertheless, some drawbacks still characterize the supervised learning paradigm employed in networks such as CNN and Retina U-Net in real-world clinical scenarios, with CT scans from different devices with different sensors' fingerprints and spatial resolution. Continuous reassessment of CADe and CADx's performance is needed during their implementation in clinical practice.

Adapted physical activity for breast cancer patients: shared considerations with two Olympic and world Italian sports champions

Breast cancer is a growing global public health concern. Thanks to the recent treatments progress, the survival rate of BC patients has significantly improved (88% of 5-year survival rate) and the number of cancer survivors has also increased. Notwithstanding these brilliant results, many BC patients have long-term side effects as pain, oedema, limited mobility, cancer related fatigue, etc. as a consequence of surgical, radiotherapy and medical treatments. For example, posture appears to be frequently altered after mastectomy, due to the impairment of the mobility of the arm caused by surgical scars. All these aspects negatively affect the health-related Quality of Life (QoL) of BC patients. Recent several randomized clinical trials have shown benefits of regular and appropriate physical activity (PA) during and after BC treatment, particularly in terms of benefits for health, reducing fatigue, improving strength levels, QoL and physical function. In this context, two types of sports have demonstrated their affinity and efficacy as treatment support during and after treatments for BC patients: fencing and rowing. Here we report considerations shared with two sport champions: the fencing Olympic gold medal Daniele Garozzo and the rowing World Champion Giovanni Ficarra, with the aim to find the adapted PA for BC patients.

Fatigue in post-acute sequelae of SARS-CoV2 (PASC) treated with oxygen-ozone autohemotherapy - preliminary results on 100 patients

OBJECTIVE

Post-acute sequelae of SARS-CoV2 infection (PASC) are a novel terminology used to describe post-COVID persistent symptoms, mimicking somehow the previously described chronic fatigue syndrome (CFS). In this manuscript, we evaluated a therapeutical approach to address PASC-derived fatigue in a cohort of past-COVID-19 positive patients.

PATIENTS AND METHODS

A number of 100 patients, previously diagnosed as COVID-19 positive subjects and meeting our eligibility criteria, was diagnosed having PASC-related fatigue. They were recruited in the study and treated with oxygen-ozone autohemotherapy (O2-O3-AHT), according to the SIOOT protocol. Patients' response to O2-O3-AHT and changes in fatigue were measured with the 7-scoring Fatigue Severity Scale (FSS), according to previously published protocols.

RESULTS

Statistics assessed that the effects of O2-O3-AHT on fatigue reduced PASC symptoms by 67%, as a mean, in all the investigated cohort of patients (H = 148.4786 p < 0.0001) (Figure 1). Patients following O2-O3-AHT therapy, quite completely recovered for PASC-associated fatigue, a quote amounting to about two fifths (around 40%) of the whole cohort undergoing ozone treatment and despite most of patients were female subjects, the effect was not influenced by sex distribution (H = 0.7353, p = 0.39117).

CONCLUSIONS

Ozone therapy is able to recover normal functionality and to relief pain and discomfort in the form of PASC-associated fatigue in at least 67% of patients suffering from post-COVID sequelae, aside from sex and age distribution.

Risk factors for myocardial injury and death in patients with COVID-19: insights from a cohort study with chest computed tomography

AIMS

Whether pulmonary artery (PA) dimension and coronary artery calcium (CAC) score, as assessed by chest computed tomography (CT), are associated with myocardial injury in patients with coronavirus disease 2019 (COVID-19) is not known. The aim of this study was to explore the risk factors for myocardial injury and death and to investigate whether myocardial injury has an independent association with all-cause mortality in patients with COVID-19.

METHODS AND RESULTS

This is a single-centre cohort study including consecutive patients with laboratory-confirmed COVID-19 undergoing chest CT on admission. Myocardial injury was defined as high-sensitivity troponin I >20 ng/L on admission. A total of 332 patients with a median follow-up of 12 days were included. There were 68 (20.5%) deaths; 123 (37%) patients had myocardial injury. PA diameter was higher in patients with myocardial injury compared with patients without myocardial injury [29.0 (25th-75th percentile, 27-32) mm vs. 27.7 (25-30) mm, P < 0.001). PA diameter was independently associated with an increased risk of myocardial injury [adjusted odds ratio 1.10, 95% confidence interval (CI) 1.02-1.19, P = 0.01] and death [adjusted hazard ratio (HR) 1.09, 95% CI 1.02-1.17, P = 0.01]. Compared with patients without myocardial injury, patients with myocardial injury had a lower prevalence of a CAC score of zero (25% vs. 55%, P < 0.001); however, the CAC score did not emerge as a predictor of myocardial injury by multivariable logistic regression. Myocardial injury was independently associated with an increased risk of death by multivariable Cox regression (adjusted HR 2.25, 95% CI 1.27-3.96, P = 0.005). Older age, lower estimated glomerular filtration rate, and lower PaO2/FiO2 ratio on admission were other independent predictors for both myocardial injury and death.

CONCLUSIONS

An increased PA diameter, as assessed by chest CT, is an independent risk factor for myocardial injury and mortality in patients with COVID-19. Myocardial injury is independently associated with an approximately two-fold increased risk of death.

Gadoxetic acid-enhanced MRI of transient hepatic enhancement differences: Another cause of hypointense observation on hepatobiliary phase

PURPOSE

To retrospectively determine the frequency, natural history and factors associated with the presence of transient hepatic enhancement difference showing hypointensity on hepatobiliary phase images of gadoxetic acid-enhanced MRI.

MATERIALS AND METHODS

Gadoxetic acid-enhanced MRI of 125 patients (91 men; 34 women) with transient hepatic enhancement difference were retrospectively reviewed. Three readers qualitatively and quantitatively evaluated MR imaging features and evolution at follow up. The Chi-square test, Fisher's exact test and Kruskall-Wallis rank test were used for statistical analysis.

RESULTS

Transient hepatic enhancement difference were hypointense on hepatobiliary phase images in 20 of 125 cases (16%). At univariate analysis there was association with wedge-shape morphology (p < 0.001), size ≥21 mm (p < 0.001), hyperintensity on T2-weighted imaging (p < 0.001), restricted diffusion (p < 0.001) and previous treatment (p < 0.005). At multivariate analysis, the following factors were associated: previous treatment (p < 0.05), hyperintensity on T2-weighted imaging (p < 0.001) and size ≥21 mm (p < 0.001). Of 12 patients with hypointense transient hepatic enhancement difference on hepatobiliary phase images who had follow-up MRI, nine showed reduction in size.

CONCLUSION

Transient hepatic enhancement difference observations showing hypointensity on hepatobiliary phase images of gadoxetic acid-enhanced MRI are not infrequent and may shrink at follow-up. They are more likely associated with size ≥21 mm, hyperintensity on T2-weighted images and previous treatment of adjacent tumor.

The cheating liver: imaging of focal steatosis and fatty sparing

Focal steatosis and fatty sparing are a frequent finding in liver imaging, and can mimic solid lesions. Liver regional variations in the degree of fat accumulation can be related to vascular anomalies, metabolic disorders, use of certain drugs or coexistence of hepatic masses. CT and MRI are the modalities of choice for the noninvasive diagnosis of hepatic steatosis. Knowledge of CT and MRI appearance of focal steatosis and fatty sparing is crucial for an accurate diagnosis, and to rule-out other pathologic processes. This paper will review the CT and MRI techniques for the diagnosis of hepatic steatosis and the CT and MRI features of common and uncommon causes of focal steatosis and fatty sparing.

Evaluation of insulin resistance in a cohort of HIV-infected youth

OBJECTIVE

Metabolic abnormalities, including impairment of glucose homeostasis, have been well characterized in HIV-infected patients. In contrast to adults, insulin resistance and diabetes mellitus appear to be relatively uncommon finding in youth.

DESIGN

We assessed insulin resistance, and associated risk factors, in a population of vertically HIV-infected children and young adults, when compared with a control population of healthy children.

METHODS

At the time of enrolment, weeks of pregnancy, birth weight, sex, age, weight, height, body mass index (BMI), pubertal stages, CDC classification, blood pressure, clinical lipodystrophy, hepatitis B or C co-infection, antiretroviral therapy, CD4 T lymphocyte counts, and HIV-RNA levels were recorded. Fasting plasma glucose and insulin levels and homeostatic model assessment-insulin resistance (HOMA-IR) were determined. These parameters were compared between HIV patients and healthy controls with multivariate analyses.

RESULTS

Fasting insulin levels (OR=1.21, P<0.001) and glycemia (OR=0.89, P<0.001) were significantly different between HIV-infected patients and controls. Antiretroviral therapy duration (r=0.281, P<0.05), triglyceride levels (r=0.286, P<0.05), age (r=0.299, P<0.05), and BMI SDS (r=0.485, P<0.001) were significant predictor variables of insulin resistance, expressed as HOMA-IR. Moreover, clinical lipodystrophy seems to be strongly correlated to glycemia (P<0.05), triglyceride levels (P<0.05), serum insulin levels (P<0.001), HOMA-IR (P<0.05), and also with therapy duration (P<0.05).

CONCLUSIONS

Both HIV infection and antiretroviral therapy demonstrate differential effects on glucose metabolism in HIV-infected children. Targeted prevention of insulin resistance and diabetes mellitus in HIV-infected children and young adults is needed in order to avoid the associated long-term complications that would otherwise occur, given the improvement in life expectancy of HIV-infected individuals.

Five-year follow-up of a cognitive-behavioural lifestyle multidisciplinary programme for childhood obesity outpatient treatment

OBJECTIVE

Aim of this study is to examine the 5-year follow-up results of MI PIACE PIACERMI (I like to like and please myself), a cognitive-behavioural programme intended to obtain a weight growth regulation over an extended period.

DESIGN

Longitudinal observational clinical study.

SETTING

Hospital-based programme, through outpatient activities.

SUBJECTS

Thirty-one simple obese children, 13 boys and 18 girls, 6-12 years of age on admission.

INTERVENTION

The intervention was carried out by a multidisciplinary team (paediatrician, cognitive-behavioural psychologist, physical therapist). It employed cognitive-behavioural techniques, nutrition education, promotion of physical activity, setting a high value on free play in motion. The programme actively involves parents. The following measurements were taken on admission and at 5-year follow-up: height, weight, waist circumference, body mass index (BMI), BMI standardized (BMI-SDS), and adjusted BMI (a-BMI) as actual BMI/BMI (50th percentile)*100. Dietary habits were investigated by interview and 24-h recall. Parents completed the Family Habit Inventory and the Child Behaviour Checklist (CBCL). Motor skills were assessed by using Frostig's test.

RESULTS

The dropout rate was 35.5%. In subjects who completed the 5-year follow-up, the mean and s.d. of BMI-SDS and a-BMI were, respectively, 4.23+/-0.71 and 54.7%+/-9.0 at baseline and 2.74+/-0.85 and 43.2%+/-17.3 at the last visit. Waist circumference decreased. Family habits improved significantly. Total energy intake was significantly reduced. Emotional and social aspects of obesity-related behaviours showed positive changes. Motor skills globally improved.

CONCLUSIONS

The study provides further evidence that positive persistent results may be obtained in obese children with treatment programmes combining a lifestyle centred approach, parental involvement, nutrition education and cognitive-behavioural strategies.

Bone quality assessed by phalangeal quantitative ultrasonography in children and adolescents with isolated idiopathic growth hormone deficiency

OBJECTIVE

Some observations indicate that GH deficiency (GHD) may have little impact on bone mineralization in contrast to its effects on bone growth and maturation. The aim of the present study was to evaluate the effects of isolated GHD and GH-replacement therapy on bone quality assessed by a quantitative ultrasound (QUS) technique at the proximal phalanges of the hand.

DESIGN

Growth and QUS data of 68 subjects (50 males and 18 females) aged 5-18 yr with isolated GHD were retrospectively examined. A cross-sectional series of 120 observations was collected and compared with data obtained from a control population (1227 healthy children, 641 males and 586 females, aged 3-16 yr).

METHODS

QUS variables amplitude- dependent speed of sound (AD-SoS) and bone transmission time (BTT) were assessed by the sonographic device DBM Sonic BP IGEA. Height and weight measurements were performed according to standard techniques. In patients, skeletal age (SA) was determined by Tanner-Whitehouse method (3rd version).

RESULTS

Before treatment height, SA, ADSoS and BTT were reduced in patients. Height SD score (SDS), SA SDS, AD-SoS SDS, and BTT SDS improved during treatment. Significant associations of both AD-SoS and BTT with age, SA, height, and therapy duration were observed. Using multivariate regression models the disease state, SA, and height proved to be significant variables in predicting BTT and AD-SoS.

CONCLUSIONS

QUS measurements adjusted for body size and skeletal maturity in GHD patients seem to be only slightly reduced. A body size and skeletal maturity adjustment should be incorporated in studies on bone mass in GHD children and adolescents. A non-invasive technique such as QUS technology opens new perspectives.

Longitudinal assessment of bone quality by quantitative ultrasonography in children and adolescents

Among the techniques available to assess bone quality, quantitative ultrasonography of the proximal phalanges of the hand (QUS) has emerged as particularly attractive. In this study, amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) were obtained by the sonographic device DBM Sonic BP IGEA in two sessions at two years' interval, in a school-age population (589 subjects, 290 mol/L and 299F, aged 3 to 16 y) with the aim to determine accuracy of QUS measurements, evaluate QUS variable changes during growth, relate these values with age and growth variables. Mean AD-SoS and BTT at age classes from 5 to 12 y as determined at the first and second measurement sessions were not significantly different. A significant increment (p < 0.0001) between the first and the second measurement was observed for both QUS variables. AD-SoS and BTT showed significantly different variations in the various age groups (ANOVA). Correlations were found of AD-SoS and BTT increments with age, height, weight, pubertal stage and with height growth velocity (p < 0.05). AD-SoS and BTT increment curves presented a very similar trend decreasing from 4 to 7 y of age. Thereafter a plateau was reached up to the age of 10 to 11 y in girls and 11 to 12 y in boys, when an increase was observed corresponding to pubertal growth rate acceleration. In conclusion, the present study would confirm that QUS measurements are accurate. Ad-SoS and BTT increment models are similar to most growth velocity curves and follow a strongly age- and growth-dependent pattern.

Fetal spine ossification: the gender and individual differences illustrated by ultrasonography

The spatial and temporal pattern of manifestation of ossification nuclei of the spinal column in fetal life have been well established by histologic and radiologic studies. Sonographic evaluation of the fetal spine depends on visualization of the ossification centers, but the sequence of development of ossification centers in the vertebral column obtained by embryologists and sonographers and radiology are conflicting. We carried out a longitudinal study to establish the ultrasonographic appearance and timing of development of primary ossification centers of the fetal spine in the first and second trimesters of pregnancy. A total of 80 mothers were evaluated during their pregnancy with two echographic controls; in the first trimester, the spine length was measured and, in the second trimester of pregnancy, the timing of ossification of the bodies and neural arches of sacral vertebrae and the difference in appearance between the female and male genders were evaluated. Spinal length measurements obtained in the first trimester and percentage of detection of sacral vertebral structures increased progressively with a regular pattern in relation to gestational age. Spinal length at first ultrasound examination was slightly correlated with time of appearance of sacral bodies and arches. Ossification timing was significantly earlier in females than in males. The study has attempted to improve our understanding of the sonographic detection of the spinal ossification. Data presented give some further information on the stages of appearance of sacral vertebrae body centers during intrauterine development. Differences between genders and interindividual variations in ossification timing were observed at a very early stage of development. This could be of value when fetal growth is evaluated. Moreover, further knowledge of spinal development may be useful for early diagnosis of spinal abnormalities and for fetal biometrics.

Transvaginal administration of progesterone

OBJECTIVE

To examine the endometrial effects of three different doses of progesterone administered vaginally.

METHODS

Forty women 25-41 years old deprived of ovarian function received estradiol (E2) for 28 days. From days 15 to 27, a new mucus-like vaginal gel of progesterone was administered every other day, randomly, dosed at 45 mg (group A, n = 14), 90 mg (group B, n = 13), or 180 mg (group C, n = 13). Plasma gonadotropins, estrone, E2, and progesterone were measured. An endometrial biopsy was performed on day 20 (n = 20) or 24 (n = 20) for endometrial dating and for estrogen and progesterone receptor determinations.

RESULTS

Plasma estrogen levels were in the menstrual cycle range. Mean progesterone levels were lower in group A (2.4 +/- 0.2 ng/mL) than in group B (3.6 +/- 0.2 ng/mL) or C (3.4 +/- 0.4 ng/mL) (P < .005). Plasma FSH and LH decreased significantly during progesterone treatment. In all groups, we observed secretory transformation in the glands (day 20) and stroma (day 24) and the distribution of estrogen and progesterone receptors seen in normal menstrual cycles.

CONCLUSION

Transvaginal administration of progesterone induced normal secretory transformation of the endometrium despite low plasma levels, suggesting a direct transit into the uterus or "first uterine pass effect."

[Physiopathology of maternal and feto-neonatal thyroid in pregnant women with endemic goiter]

Endemic goitre is a socially important disease in many regions of Italy. In conditions of euthyroidism, the course of pregnancy and perinatal outcome are not burdened by significant complications. It is useful to control thyroid function and to start L-thyroxine therapy in order to avoid any further increase in thyroid size owing to the goitrogenic effect of pregnancy and to avoid transient hypothyroidism and the nodular evolution of goitre. Recent studies appear to indicate a possible physiological role for thyroid hormones in the development of the fetal CNS as early as conception, an additional motive for the administration of thyroxine in order to prevent pathologies caused by thyroid hormone deficiency in utero.

[Ovarian stimulation using a protocol of low dose agonist in patients with an elevated basal FSH]

This study compare the ovarian response of patients with high day 3 FSH (> 6.5 UI/L), treated with two protocols; a protocol with a low dose of GnRH agonist and a so called "long protocol" with GnRH agonist in a depot formula. The ovarian response with the agonist low dose was better with less ampules (37.1 vs 46.6) and a shorter duration of stimulation (10.5 vs 12.4 days). The number of mature oocyte was higher (5.9 vs 4.5) as well as the number of good quality embryo (3.2 versus 2.3). The E2 levels on day 8 was higher (1065 vs 460 pg/ml). The cancellation rate was lower (14% vs 26%). The use of the low dose protocol gave a better ovarian response for patients with high 3 FSH. Large randomized studies are needed to confirm these data.

A protocol using a low dose of gonadotrophin-releasing hormone agonist might be the best protocol for patients with high follicle-stimulating hormone concentrations on day 3

We studied 98 in-vitro fertilization (IVF) patients with a high basal follicle stimulating hormone (FSH; >6.5 IU/l) concentration on day 3 who were treated with a low dose gonadotrophin-releasing hormone agonist (GnRHa) protocol and who had received in the previous 6 months a long protocol with GnRHa in a depot formula. The evaluation was made using the previous IVF cycle of the same patient as a control. The mean +/- SD age of the patients was 34.1+/-4.2 years. The use of a low dose agonist protocol ended with significantly less ampoules (37.5 versus 46.1), a shorter duration of stimulation (10.7 versus 12.3 days), a higher oestradiol concentration on day 8 (1068 versus 495 pg/ml), a higher number of mature oocytes (5.9 versus 4.4) and a higher number of good quality embryos (3.3 versus 2.3). The cancellation rate was lower (11 versus 24%). A GnRHa low dose protocol may be the protocol of choice for patients with high FSH concentrations on day 3. Larger randomized studies are needed to confirm these data.

Immunolocalization, binding, and biological activity of endothelin in rabbit uterus: effect of ovarian steroids

Specific immunostaining for endothelin 1 (ET-1) was observed in the endometrium but not myometrium of rabbits. The staining was dramatically affected by subacute treatment with ovarian steroids: epithelial cells were predominantly positive in immature rabbits, whereas, in sex steroid-primed rabbits, ET-1 was mainly localized in the stromal compartment. Binding studies were performed in myometrium of estrogen-treated rabbits using labeled ET-1 and ET-3, the corresponding unlabeled peptides, and sarafotoxin b (SRTX). Mathematical modeling of experimental results indicates that two populations of sites are present in myometrium. One site (R1 = 1 pmol/mg protein) shows approximately the same affinity for ET-1, ET-3, and SRTX [dissociation constant (Kd) 100 pM], whereas the second site (R2 = 10 pmol/mg protein) selectively binds ET-1 (Kd 400 pM). According to binding studies, ET-1 was more potent than SRTX in stimulating uterine contraction "in vitro." The subacute administration of increasing concentrations of 17 beta-estradiol (0.2-200 micrograms/kg for 4 days), but not 17 beta-estradiol (200 micrograms/kg for 4 days) plus progesterone (5 mg/kg for 4 days), stimulates a dose-dependent increase in endothelin receptors in myometrium (half-maximal effective dose = 0.7 micrograms/kg for 4 days). However, estrogen treatment does not affect the concentration of endothelin receptors in myometrial cells in primary culture. Conversely, divalent ions like calcium and magnesium enhance the binding of ET-1 to both uterine membranes and cells. Our results indicate that in rabbit uterus endothelin is present in the endometrium, whereas specific receptors are located in myometrium.

Human myometrium during pregnancy contains and responds to V1 vasopressin receptors as well as oxytocin receptors

We have recently demonstrated the presence of two classes of neurohypophysial hormone receptors in the vagina, myometrium, and oviduct of rabbit: an oxytocin (OT) site and a V1 arginine vasopressin (AVP) site. We now report binding and in vitro contractility studies on human myometrial specimens obtained at cesarean section from women at the end of pregnancy. The program Ligand was used to analyze self- and cross-displacement curves for labeled OT, AVP or its V1 antagonist d(CH2)5TyrMeAVP, the corresponding unlabeled peptides, and selective analogs. Our results clearly indicate the presence of heterogeneity of binding sites in human uterus. Blocking experiments were performed to evaluate the density of OT and V1 AVP receptors in individual uterine specimens. The contractile response of the same samples to OT, AVP, and analogs was also evaluated. Our results indicate that V1 AVP receptors are present in all of the uterine specimens investigated, with virtually equal density from 32 weeks to term. AVP and the V1-selective agonist [Phe2,Ile3,Orn8]VP stimulate contractility of uterine strips, an effect blocked by nanomolar concentration of the V1 antagonist d(CH2)5TyrMeAVP. Uterine OT receptors increase during late pregnancy, peaking in early labor. A significant correlation between the density of OT receptors and the frequency of uterine contractions (external tocography) was found in pregnant women before surgery. OT stimulated in vitro contractility of uterine strips only when the density of receptors was more than 150 fmol/mg protein. In conclusion, we identified biologically active V1 AVP receptors in human uterus at the end of gestation and confirmed the primary relevance of OT receptors in human parturition.

Vasopressin and oxytocin receptors in vagina, myometrium, and oviduct of rabbits

In view of the presence of distinct oxytocin (OT) and vasopressin (VP) receptors in the male genital tract (porcine) we have reexamined the receptors for OT and AVP in the classical OT target tissue, female genital tract (rabbit). Neurohypophysial hormone receptors have been investigated in vagina, myometrium, and oviduct using quantitative ligand binding, adenylate cyclase, and contractility studies. Our results clearly indicate the presence of distinct OT and V1 VP receptors in the myometrium, while only the latter was detected in vagina and oviduct. In myometrium, estrogen treatment increases the density of OT and AVP receptors, while progesterone administration inhibits the estrogen effect. At the time of spontaneous delivery a dramatic (17-fold) increase was observed for the OT sites, while the AVP sites were unchanged. AVP receptors in vagina were sensitive to sex steroid administration and were reduced during pregnancy and delivery. Isometric contractility studies suggest that not just OT, but AVP can stimulate uterine strips, an effect that is partially reversible by the V1 antagonist d(CH2)5TyrMeAVP. In vagina only AVP is effective in inducing contractions at nanomolar concentrations. These results suggest a role for AVP as well as OT in regulation of the motility of female genital tract.