Impact of long-term naltrexone treatment on growth hormone and insulin secretion in hyperandrogenic and normal obese patients

The growth hormone (GH) response to stimulation tests is impaired in obesity. Moreover, obese patients exhibit a "paradoxical" increase of GH to GH-releasing hormone (GHRH) stimulation after food ingestion; this paradoxical response is reversed by naloxone infusion. On the other hand, beta-endorphin seems to exert profound effects on insulin release. Recent studies also demonstrated an impairment of GH response to several stimuli in polycystic ovary syndrome (PCOS), a condition associated with obesity, hyperinsulinism, and insulin resistance. Chronic inhibition of opioid tone by the opioid antagonist naltrexone (NTX) is able to reduce the insulin response to an oral glucose tolerance test (OGTT) in hyperinsulinemic PCOS patients. Since insulin and GH may reciprocally influence their secretion and the opioid system may have a role in the pathogenesis of hyperinsulinemia and reduced GH secretion, we have explored the involvement of these neuroendocrine mechanisms in essential obesity and in obesity associated with hyperandrogenism by a long-term treatment with an opiate antagonist. We tested seven obese patients affected by PCOS, seven matched women with essential obesity (EO), and five non-obese control subjects. All patients, in the follicular phase, underwent an OGTT (75 g) and basal hormone assay. Two days later, patients were subjected to a GHRH test. The patients then had 4 weeks of treatment with NTX 50 mg/d. Following continuation of the treatment, OGTT and GHRH tests were repeated. Insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 (IGFBP-3) plasma concentrations were also determined in the basal condition before and after NTX treatment. NTX treatment reduced fasting insulin levels in patients with EO (P < .05) and restored a normal GH response to GHRH without affecting IGF-1 and IGFBP-3 levels. In PCOS subjects, NTX reduced the insulin response to a glucose load and failed to modify the blunted GH response to GHRH. Our data suggest a significant difference in opioid system function in PCOS and EO subjects, indicating a particular form of obesity in PCOS. The opiate antagonist treatment in EO may act through the reduction of negative insulin feedback on GH secretion. In PCOS patients, the failure to improve GH secretion in obese hyperandrogenized patients may be related to a high opioidergic tone or to the inhibitory predominance of other neurotransmitters.

The use of prostaglandin E2 for cervical ripening in patients requiring induction of labour

A total of 290 women who required induction of labour for medical or obstetric reasons were given single or multiple doses of prostaglandin E2 gel (0.5 mg) to induce cervical ripening. Onset of labour occurred in 185 (63.8%) of the women treated with the gel, without any further treatment. The overall Caesarean section rate was 27.2% (79/290) and was significantly higher among those with an initially low Bishop score than in those with a higher initial score (34.7% versus 22.1%; P = 0.025). Prostaglandin E2 gel appears to be of considerable clinical benefit, especially where no other options are available except Caesarean section or a very long, difficult labour that may result in significant fetal distress.

T cells from individuals in advanced stages of HIV-1 infection do not proliferate but express activation antigens in response to HIV-1-specific antigens

Like T cells from healthy subjects, those of HIV-1-infected patients are capable of expressing activation antigens on their surface after antigenic or mitogenic stimulation, but their proliferative activity is strongly reduced or even absent, especially in patients with advanced stages of the disease. The characteristic of expressing activation antigens in response to different stimuli in the absence of cell proliferation is shared by CD4+ and CD8+ T-cell subsets from HIV-1-infected patients. The number of T cells capable of expressing CD25 and CD71 in response to HIV-1-related antigens but not of proliferating increased significantly with the progression of the disease, but the number of T cells capable of expressing the two activation antigens in response to the classic tetanus toxoid recall antigen decreased. The higher numbers of T cells capable of responding to HIV-1-related antigens in conjunction with a reduction in the number of T cells responding to recall antigens may explain the occurrence of different infections, including opportunistic microorganisms, during the more advanced stages of HIV-1 infection. Because the increase in the number of HIV-1 antigen-responding T cells (defined by CD25 and CD71 activation antigen expression) is a characteristic of symptomatic HIV-1-infected patients, expression (by flow cytometry) of these activation antigens on T cells in response to HIV-1 antigens could be used as a new marker of disease progression.

Ciliary neurotrophic factor activates JAK/Stat signal transduction cascade and induces transcriptional expression of glial fibrillary acidic protein in glial cells

In recent reports, ciliary neurotrophic factor (CNTF) has been implicated as an injury factor involved in regulating astrogliosis in the CNS. In this study, we used a rat oligodendroglial progenitor cell line that is highly responsive to CNTF to examine CNTF-induced alterations that may play a role in activation of the glial fibrillary acidic protein (GFAP) gene. We determined that CNTF induces the transient translocation of Stat1 alpha/p91 to the nucleus. This nuclear translocation was followed by GFAP promoter activation and an up-regulation of GFAP mRNA and protein. Level of CNTF-alpha receptor mRNA, however, were unaffected by addition of the ligand. Transfection studies using an upstream 5'-flanking, 1.9-kb rat GFAP promoter linked to a luciferase reporter gene revealed CNTF-induced transcriptional activation within 1 h of ligand exposure. Moreover, serial-deleted constructs identified a distal (-1,857 to -1,546 bp) and a proximal (-384 to -106 bp) region as being important for CNTF-induced GFAP promoter activation. These two regions showed a strong degree of overlap for CNTF- and serum-induced activation of the GFAP gene. Analysis of the two regions revealed several cis-elements that are thought to be involved in GFAP regulation and/or the regulation of other genes by members of the interleukin-6 family of cytokines. Moreover, we are the first to report the presence of several putative CNTF-responsive elements within our identified distal and proximal regions in the GFAP gene promoter.

The neuroprotective activity of group-II metabotropic glutamate receptors requires new protein synthesis and involves a glial-neuronal signaling

The group-II metabotropic glutamate (mGlu) receptor agonists (2S,1'R, 2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine (DCG-IV), S-4-carboxy-3-hydroxyphenylglycine (4C3HPG), and (2S,1'S, 2'S)-2-(carboxycyclopropyl)glycine (L-CCG-I) protected mouse cortical neurons grown in mixed cultures against excitotoxic degeneration induced by a 10 min pulse with NMDA. Protection was observed not only when agonists were added in combination with NMDA but also when they were transiently applied to cultures 6-20 hr before the NMDA pulse. In both cases, neuroprotection was reduced by the group-II mGlu receptor antagonist (2S,1'S,2'S,3'R)-2-(2'-carboxy-3'-phenylcyclopropyl)glycine (PCCG-IV), as well as by the protein synthesis inhibitor cycloheximide (CHX). Both neurons and astrocytes in mixed cultures were immunostained with an antibody that recognized mGlu2 and mGlu3 receptors in recombinant cells. To determine whether astrocytes played any role in the neuroprotection mediated by group-II mGlu receptors, we exposed pure cultures of cortical astrocytes to DCG-IV, 4C3HPG, or L-CCG-I for 10 min. The astrocyte medium collected 2-20 hr after the exposure to any of these drugs was highly neuroprotective when transferred to mixed cultures treated with NMDA. This protective activity was reduced when CHX was applied to astrocyte cultures immediately after the transient exposure to group-II mGlu receptor agonists. We conclude that neuroprotection mediated by group-II mGlu receptors in cultured cortical cells requires new protein synthesis and involves an interaction between neurons and astrocytes.

Thrombolysis for prosthetic valve thrombosis: indications and results

BACKGROUND AND AIMS OF THE STUDY

Prosthetic valve obstruction is caused by thrombi or fibrous tissue overgrowth, or both; thrombolysis avoids reoperation-related risks, but is effective only on clots. Hence, the study aims were to: (i) further assess our indication criteria for thrombolysis in prosthetic valve thrombosis; and (ii) evaluate treatment and follow up in a large patient population.

METHODS

Between January 1991 and January 1994, 20 cases of prosthetic thrombosis were treated with thrombolysis using recombinant tissue type plasminogen activator (rt-PA). Indication criteria for thrombolysis were: (i) recent onset of symptoms; (ii) transesophageal echocardiographic (TEE) evidence of clots on the valve or cardiac chambers; and (iii) a partially preserved disc excursion. All patients were fitted with mechanical valves (four caged balls, 10 tilting discs, six bileaflets), with 17 valves located in the mitral and three in the aortic position. Symptoms of obstruction comprised cardiac failure in 11 cases and/or embolism in 10.

RESULTS

After rt-PA infusion, normal prosthetic function was restored in all patients, though one underwent successful reoperation five days later. During infusion, five patients had a transient ischemic attack and one a minor transient peripheral embolism. Recurrence of thrombosis occurred in three patients during follow up; subsequent thrombolysis was successful in two, without complication.

CONCLUSIONS

As treatment proved satisfactory, the reliability of our indicational criteria was confirmed. Only transient complications arose during treatment with recurrent thrombosis most common in those patients who had more thrombogenic valve prostheses.

The impact of insulin secretion on the ovarian response to exogenous gonadotropins in polycystic ovary syndrome

The aim of the study was to evaluate the influence of insulin level on the ovarian response to FSH when inducing ovulation in patients affected by polycystic ovarian syndrome (PCOS). To evaluate the presence of hyperinsulinemia, 34 patients affected by PCOS were studied by an oral glucose tolerance test, then patients were stimulated for 52 cycles using FSH to induce ovulation. The ovarian response to therapy was evaluated by ultrasounds and as estradiol (E2) and androstenedione (A) plasma level determinations. On the basis of the insulinemic response to the glucose challenge, 20 patients were considered to be hyperinsulinemic and 14 normoinsulinemic. The hormonal features of each group were similar. The ovulation rate was similar in hyperinsulinemic and normoinsulinemic subjects, whereas the incidence of ovarian hyperstimulation was significantly higher in the hyperinsulinemic group. The increase in ovarian dimensions observed in hyperinsulinemic subjects after gonadotropin stimulation was more marked than that observed in normoinsulinemic ones. This was caused by the development of a larger number of immature follicles. E2 levels gradually increased after gonadotropin stimulation in both groups of subjects; however, higher levels were observed in hyperinsulinemic patients. During stimulation, the higher E2/A ratio suggests the presence of a greater aromatization activity in hyper-insulinemic patients. In conclusion, the present study suggests that, in PCOS, the insulinemic pattern may influence the ovarian response to gonadotropin administration; thus, hyperinsulinemic subjects may be at greater risk of ovarian hyperstimulation syndrome than normoinsulinemic subjects.

Natural antibodies to IL-2

Natural antibodies to human interleukin-2 are present in sera of patients infected with human immunodeficiency virus and also, at a lower titre, in sera of healthy individuals. These antibodies could be purified by affinity-chromatography. Purified human anti-hIL-2 antibodies can interfere with lymphocyte proliferation both in the lymphokine activated killer cell assay and in the mixed lymphocyte culture. The neutralizing activity observed in vitro suggests that these antibodies play a role in the elaborate cytokine network by which the immune system regulates its response.

Flow cytometric analysis of activation markers on stimulated T cells and their correlation with cell proliferation

The expression of activation antigens, namely CD25, CD69, CD71, and HLA-DR on T cells from 15 healthy individuals stimulated with different mitogens and specific antigens was evaluated by immunofluorescence assay and flow cytometric analysis and compared with cell proliferation as a function of [3H]thymidine incorporation. CD69 was the earliest expressed antigen on stimulated cells, while HLA-DR was the latest. Regardless of the stimulus used, lymphocytes expressing CD25 and CD71 were always more numerous than cells expressing CD69 and HLA-DR. Variations in the proportion of CD4+ and CD8+ T cells expressing each activation marker were observed with different antigenic stimuli. The expression of each activation marker showed overall agreement with the [3H]thymidine incorporation assay in discriminating between positive and negative immune response. However, no correlation was observed between the percentage of CD25-, CD69-, CD71-, and HLA-DR-positive T cells and the amount of [3H]thymidine incorporation. Moreover, low doses of mitogens and antigens as well as short time of stimulation were sufficient to induce T cells to express activation antigens but not to proliferate. Our data show that results obtained by flow cytometry and [3H]thymidine incorporation may differ qualitatively, at least under certain conditions; this suggests that the 2 assays are complementary, and when combined, may gives a clearer understanding of events leading to efficient cell-mediated immune response.

Natural antibodies to interferon-gamma

Natural antibodies to interferon (IFN)-gamma were detected in the serum of virus-infected patients and also, at a low titre, in the serum of healthy subjects. The increased titre of antibodies to IFN-gamma in the sera of virus-infected patients, and its decrease with clinical resolution, indicate that these antibodies are related to viral infection and probably reflect IFN-gamma production as a result of antigenic stimulation in vivo. Natural antibodies to IFN-gamma were affinity purified and studied for their capability to interfere in vitro with the multiple activities of the lymphokine. Data obtained show that these human anti-IFN-gamma antibodies have no inhibitory effect on the antiviral and antiproliferative activity of IFN-gamma and do not interfere with the binding of the lymphokine to its specific cell receptor. Instead, they can inhibit the expression of HLA-DR antigens induced by IFN-gamma on U937 cells and interfere, in mixed lymphocyte culture, with the proliferation of lymphocytes and the generation of cytotoxic lymphocytes. Experiments in animal models suggest that natural antibodies to IFN-gamma may have a role in the immunoregulatory process limiting the intensity and/or duration of immune response. As they can interfere only with the immunomodulating activities of IFN-gamma, these antibodies might open up new therapeutic approaches to diseases with evidence of activated cell-mediated immunity.

Somatostatin treatment reduces the exaggerated response of adrenocorticotropin hormone and cortisol to corticotropin-releasing hormone in polycystic ovary syndrome

OBJECTIVE

To evaluate the influence of somatostatin analogue (octreotide) in the function of hypothalamic-pituitary-adrenal (HPA) axis in women with polycystic ovary syndrome (PCOS).

SETTING

Women referred to the Department of Obstetrics and Gynecology, Università Cattolica del Sacro Cuore.

PATIENT(S)

Twelve PCOS women and 12 normo-ovulatory controls.

INTERVENTION(S)

In early follicular phase, I microgram/kg human corticotrophin-releasing hormone (CRH) was injected at 9:00 A.M. and blood samples were collected for 90 minutes after stimulus; ACTH and cortisol plasma levels were measured. The following day at 8:00 A.M., PCOS patients received an ACTH test (250 micrograms IV) and samples were collected 60 minutes after injection. After 6 weeks of octreotide treatment (100 mg s.c. twice daily), PCOS patients repeated the same study.

MAIN OUTCOME MEASURE(S)

Plasma cortisol and ACTH concentrations.

RESULT(S)

The ACTH and cortisol baseline levels were similar in PCOS and control patients. The responses to human CRH of ACTH (incremental area = 437.86 +/- 188.7 versus 175.78 +/- 87.6 pmol/L; mean +/- SD) and cortisol (incremental area = 17,293.6 +/- 4,320.3 versus 5,885 (912.1 nmol/L) were significantly greater in PCOS with respect to control subjects. After octreotide treatment, ACTH response significantly decreased and no difference was observed with respect to controls (incremental area = 176.94 +/- 91.4). Cortisol responses were decreased by treatment. However, they remained significantly higher than in controls. Treatment did not modify adrenal response to IV ACTH.

CONCLUSION(S)

Data suggest that, in the HPA axis, hyperfunction of PCOS somatostatin could be involved partially.

Protective action of epidermal growth factor and a fraction from Triticum vulgare extract in mouse tail necrosis

Several peptide growth factors, including EGF, are known to protect endothelium from oxygen-related damage or ischemia-reperfusion, in vitro experiments show that such protective effect involves endogenous endothelium-related factors like nitric oxide and prostanoids. However, in vivo demonstrations of a possible role in related vascular diseases are lacking. In our experiments, human EGF and fraction C, a 3-10 kDa oligosaccharidic fraction from an aqueous extract of Triticum vulgare, known as growth promoters for several cell types including endothelial cells, were found protective against ischemic necrosis of the mouse tail induced by i.v. k-carrageenin plus endothelin-1. After i.p. injection, peak activities were observed at 10 micrograms/kg EGF and 2 mg/kg fraction C. Pretreatment with L-NAME reduced protection in a dose-dependent manner. Addition of indomethacin increased the effect of L-NAME, suggesting that both nitric oxide and eicosanoids are involved in the protective effect of EGF and fraction C.

Heat-killed Bacillus subtilis inhibits T-cell proliferative response to mitogens and recall antigens

Heat-killed vegetative forms of Bacillus subtilis were found to impair considerably the capacity of human T-lymphocytes to secrete interleukin-2 (IL-2) and to proliferate (in terms of [3H]thymidine incorporation) after phytohaemagglutinin (PHA) stimulation. B. subtilis was also found to interfere with T-cell proliferation induced by concanavalin A (Con A) and the recall antigen tetanus toxoid (TT). The suppressive activity was dependent on bacterial concentration, and was not ascribed to mitogen, medium-nutrient absorption or cell killing. Moreover, B. subtilis did not interfere with mitogen-induced IL-2 receptor expression on the T-cell surface. On the other hand, B. subtilis did not interfere with T-cell proliferation induced by phorbol myristate acetate (PMA) and ionomycin stimulation. All data obtained suggest the binding of B. subtilis subcomponents to- or very close to-the T-cell receptor (TCR). Identification and purification of the basic structure(s) or component(s) of B. subtilis with TCR antagonist activity in vitro will help to exploit different aspects of T-cell activity and development, and possibly, will provide a means of specific control or modification of the immune response.

Growth hormone enhances estradiol production follicle-stimulating hormone-induced in the early stage of the follicular maturation

OBJECTIVE

To investigate the ability of GH to increase the steroidogenic response of the ovary to FSH in the early stage of human follicle development in vivo.

DESIGN

Ovarian sensitivity to FSH and/or GH during the early follicular phase of the human menstrual cycle was evaluated in a prospective study.

SETTING

Normal human volunteers in the Department of Obstetrics and Gynecology, Università Cattolica Sacro Cuore.

PATIENT(S)

Twenty-four normal patients with normo-ovulatory cycles and tubal factor infertility.

INTERVENTION(S)

Pure urinary FSH (75 IU) or saline were injected IV in the early follicular phase with or without a pretreatment with human GH (0.1 IU/kg IM for 3 days).

MAIN OUTCOME MEASURE(S)

Plasma levels of LH, FSH, E2, and T in samples collected for a period of 26 hours after saline or FSH IV injection.

RESULT(S)

Follicle-stimulating hormone injection increased E2 and E2:T stimulated area under the curve (AUC) with respect to saline administration. Moreover, the E2 secretion was increased significantly in the group treated with GH plus FSH as compared with that found in the group receiving FSH alone. Growth hormone itself was unable to increase any steroidogenic response by ovary in terms of both E2 and E2:T AUC values.

CONCLUSION(S)

The results of present study demonstrate in vivo a synergistic effect of GH on the FSH-induced follicular steroidogenesis, suggesting a potential relevance of GH in the reproductive biology.

Transvaginal color Doppler ultrasonography in the presurgical characterization of adnexal masses

The aim of our study was to evaluate flow-velocity waveforms from ovarian tumors with color Doppler, in order to test the predictivity of malignancy and to compare the Doppler technique with some morphological scoring systems. Color Doppler examination of ovarian neoplasms was performed in 122 patients within 2-3 days from surgery and, based on vascular characteristics and on Doppler resistance index, a "vascular" score was calculated. One hundred one women had benign and 21 had malignant tumors on histopathology. In all of the malignant lesions color Doppler was able to detect vascular patterns, whereas only 43% of the benign tumors showed recognizable vessels (P < 0.001). Malignant masses showed significantly greater vascular scores than those of benign tumors (P < 0.001). Doppler ultrasonography achieved better specificity and PPV when compared to morphological scores (96% vs 61-75% and 82% vs 35-48%). Color Doppler ultrasonography of ovarian tumors seems to be a reliable method in the presurgical characterization of ovarian neoplasms.

Preconceptional and gestational evaluation of insulin secretion in patients with polycystic ovary syndrome

The relationship between insulinaemia and obesity and glucose tolerance and the impact of pregnancy as risk factor for carbohydrate abnormalities were investigated in 91 consecutive patients with polycystic ovary syndrome (PCOS) aged 26-32 years. Fifteen normoglycaemic patients became pregnant within 6 months of the pregestational study using pharmacological induction of ovulation. Plasma concentrations of insulin and glucose after an oral glucose tolerance test (OGTT) were determined by immunoradiometric assay and glucose oxidase technique respectively. OGTT patients were classified according to their response as normoinsulinaemic (n = 46) or hyperinsulinaemic (n = 45). Impairment of glucose metabolism occurred in 12.1% (n = 11, 10 obese and one lean) of all PCOS subjects. Based on insulin secretion, 6.5% of normoinsulinaemic and 13.3% of hyperinsulinaemic patients had an impaired glucose tolerance and 2.3 and 2.2% respectively a non-insulin-dependent diabetes mellitus. Obese patients had higher values for area under the curve for insulin response to OGTT (I-AUC values) than lean patients, and the percentage above ideal body weight was greater in hyperinsulinaemic than in normoinsulinaemic patients. All hyperinsulinaemic (7/15) subjects who became pregnant developed an impairment of glucose metabolism during pregnancy. It is concluded that the PCOS population was at higher risk of developing carbohydrate abnormalities than the normal population of a similar reproductive age. Furthermore, those with abnormal insulin secretion at the pregestational stage may, during pregnancy, develop an impaired gestational glucose tolerance or gestational diabetes.

Effect of follicular fluid on granulosa luteal cells from polycystic ovary

Recent data suggest that follicular fluid may play an important role in the endocrine balance of polycystic ovary syndrome, probably by acting on the theca-granulosa cell relationship. The aim of this study was to evaluate the effect of steroid-free follicular fluid on steroidal response and cell proliferation of human granulosa luteal cells from polycystic (POGC) and normal ovary (NC). Granulosa cells (from both POGC and NC) were cultured for 48 h with or without increasing dilutions of follicular fluid (FF) obtained from polycystic (FFp) and normo-ovulating (FFc) patients. Both follicular fluids were able to elicit aromatase activity as well as progesterone production and thymidine incorporation. POGC, when incubated with FFp, showed a lower increase of aromatase activity and progesterone production with respect to NC. Furthermore, the proliferation rate was increased by incubation with either follicular fluid, but the increase was less with FFp compared to FFc. Aromatase/[3H]thymidine (A/T) and progesterone/ [3H]thymidine (P/T) ratios could be considered to be representative of the contribution of the single cell unit to steroidogenesis. Using high concentrations of either follicular fluids, POGC showed a higher A/T ratio compared with NC. Moreover, the same treatment strongly decreased P/T ration in POGC, while it was ineffective in NC. Our study show that an abnormal interaction between POGC and their own follicular fluid can be implicated in the pathogenesis of the altered steroidal response in these cells, and that in particular it could affect the proliferation rate.

Molecular cloning and characterization of murine interleukin-11

Human interleukin-11 (IL-11) has been shown to have pleiotropic action on hematopoietic, hepatic, stromal, epithelial, neural, and osteoclast cells. In the present work, the murine IL-11 cDNA has been isolated from a fetal thymic cell line, and its structure and function compared with human IL-11. The murine protein was demonstrated to have identical actions on the proliferation of a murine plasmacytoma cell line, murine primitive bone marrow progenitor cells, and megakaryocyte precursors. The murine IL-11 protein was synthesized as a soluble thioredoxin-IL-11 fusion in Escherichia coli and the expression of murine IL-11 was examined by pulse-chase radiolabeling in COS cells. The chromosomal location of the murine IL-11 gene was assigned to the proximal arm of chromosome 7.

Episodic secretion of activin A in pregnant women

The aim of the present study was to determine the characteristics of activin A secretion in women with normal and abnormal pregnancy. With this purpose, a prospective study was done to evaluate the putative pulsatile pattern of serum activin A in serial specimens of blood collected during a certain amount of time (every 15 min for 3 h). A group of pregnant women (N = 24) participated in a cross-sectional study. They were subdivided into three groups: healthy pregnant women (N = 8), patients with preterm labor (N = 8) and patients with gestational diabetes (N = 8) before and after insulin therapy. Secretory pulses of serum activin A were determined in all patients with a specific frequency and amplitude by using two different computerized analyses, i.e. DETECT and CLUSTER. Mean +/- SEM values of serum activin A were significantly higher in patients with preterm labor and gestational diabetes than in controls (p < 0.01), showing a significant decrease following insulin therapy in diabetic patients (p < 0.01). Specific pulses of serum activin A levels were observed in all women. The mean pulse frequency did not change significantly between healthy controls and the different pathological groups. Patients with gestational diabetes after insulin therapy showed a pulse frequency that was significantly higher than in controls (p < 0.05). When the mean peak amplitude of activin A pulses was evaluated, patients with preterm labor or gestational diabetes showed values that were significantly higher than in healthy pregnant women (p < 0.01) A significant, inverse correlation between pulse frequency and amplitude was found both in healthy pregnant women (p < 0.05) and in patients with gestational diabetes (p < 0.001). The present study showed that circulating activin A levels in pregnant women change in a pulsatile pattern whose pulse amplitude is modified in the presence of gestational diseases, such as preterm labor or gestational diabetes.

Double shunt in a case of fetal low-level obstructive uropathy

This report describes a pregnant woman at 22 weeks of gestation examined for fetal bilateral dilated renal pelvis and oligohydramnios. Ultrasound evaluation confirmed the diagnosis of low-level obstructive uropathy. At 26 weeks of gestation, the increase in hydronephrosis prompted us to introduce a vesicoamnionic shunt. Because of unusual intraperitoneal dislocation of the shunt and an increase in ascites and hydronephrosis, we had to insert a peritoneoamnionic shunt at 30 weeks of gestation. The patient underwent cesarean section at 31 weeks for obstetric complications. The infant, at 15 months of age, showed mild renal failure.

Insulin-like growth factor (IGF)-I and IGF-II stimulate progesterone production by human luteal cells: role of IGF-I as mediator of growth hormone action

OBJECTIVE

To examine the possible direct effect of insulin-like growth factor (IGF)-I and IGF-II on basal and hCG-stimulated P production by cultured human luteal cells. The possible role of IGF-I as mediator of GH action on luteal steroidogenesis also was investigated.

DESIGN

Cultures of human luteal cells from early and midluteal phase.

SETTING

All corpora lutea were obtained from the Obstetrics and Gynecology Department of the Universita Cattolica, a public care center.

PATIENTS

Eight nonpregnant women between 35 and 47 years of age underwent surgery for various nonendocrine disorders such as leiomyomatosis.

INTERVENTIONS

Corpora lutea were obtained at the time of hysterectomy.

MAIN OUTCOME MEASURES

Luteal cells were incubated with IGF-I or IGF-II with or without hCG at different concentrations. Growth hormone also was used alone and with an anti-IGF-I-antibody.

RESULTS

We found that IGF-I and IGF-II were able to stimulate directly the P production at all used concentrations and that both of them significantly amplified the steroidogenic hCG effect. Finally, IGF-I was shown to mediate the positive GH action on P synthesis.

Amylin given by central or peripheral routes decreases gastric emptying and intestinal transit in the rat

The effect of rat amylin on gastric emptying and intestinal transit in the rat was examined. Amylin administered intracerebroventricularly (1, 2, 2.5 or 4 micrograms/rat) produced the maximal decrease in gastric emptying and intestinal transit at the dose of 2.5 micrograms/rat. Higher doses produced a lower effect. Peripheral administration (25, 50 or 100 micrograms/kg) produced dose-dependent effects. Pre-treatment with neostigmine blocked the effect of amylin when it was centrally injected, while the effect of amylin given peripherally was partially reduced. Pre-treatment with domperidone decreased the inhibitory effect of peripherally injected amylin, but no effect was observed when the peptide was centrally injected.