Search PubMed⌕ Search

Biomedical subjects

F Petraglia

Publications and source records attributed to F Petraglia.

407 records · Page 23Linked to original sources

Evidence for local stimulation of ACTH secretion by corticotropin-releasing factor in human placenta.

The hypothalamic-pituitary-adrenocortical axis is activated in pregnancy and parturition. Levels of immunoreactive corticotrophin releasing factor (irCRF), immunoreactive adrenocorticotropic hormone (irACTH) and cortisol concentrations in maternal plasma are elevated throughout gestation, increase further during labour and fall precipitously after parturition. The placenta contains biologically active CRF and ACTH and it has been suggested that the placenta produces these peptides during pregnancy. Here we show that irCRF is located in the cytotrophoblast cells of placenta collected at term. Using a monolayer primary culture of human placental cells we have found that CRF stimulates secretion of peptides containing the ACTH sequence in the placenta in a dose-dependent manner, as it does in the pituitary. This effect is reversed by a CRF antagonist and is mimicked by dibutyryl cyclic AMP and forskolin. Glucocorticoids, which suppress the secretion of pituitary ACTH, were found to have no influence on release of irACTH by the placenta. Oxytocin and prostaglandins stimulate irACTH and irCRF secretion from cultured placental cells and the irACTH-releasing activity of two prostaglandins is partially reversed by a CRF antagonist. Thus CRF may be involved in the paracrine regulation of placental irACTH secretion.

Adrenocorticotropic Hormone↗

Reduced ACTH content in cerebrospinal fluid of children affected by cryptogenic infantile spasms with hypsarrhythmia.

In view of the therapeutic efficacy of adrenocorticotropic hormone (ACTH) in the treatment of infantile spasms (IS) with hypsarrhythmia, we studied the cerebrospinal fluid (CSF) levels of ACTH in 15 children (4-10 months) affected by IS with hypsarrhythmia (eight cryptogenic forms, seven secondary to perinatal distress) and in age-matched controls. Lumbar puncture was performed in all but one case before any kind of treatment. In another case, CSF was collected 3 weeks after a spontaneous remission. Both ACTH and beta-endorphin (beta-EP), the other peptide related to the same precursor (proopiomelanocortin), were measured by specific radioimmunoassay after gel chromatography. While beta-EP levels were unchanged in the two groups of patients, ACTH concentrations of cryptogenic (3.75 +/- 2.40 fmol/ml, Mean +/- SD p less than 0.05) and secondary (6.36 +/- 3.70, NS) forms were lower than in controls (10.90 +/- 5.79). On the other hand, ACTH was higher in the case studied after therapy (9.0) and in the case presenting a spontaneous clinical and EEG remission (15.0). These data indicate that in children affected by IS with hypsarrhythmia (mainly of cryptogenic type), CSF levels of ACTH are lower, while levels of beta-EP remain normal. It would therefore appear that central ACTH content may play a possible role in the pathogenesis of IS with hypsarrhythmia.

Adrenocorticotropic Hormone↗

Lack of effect of psychosocial stress on maternal corticotropin-releasing factor and catecholamine levels at 28 weeks' gestation.

OBJECTIVE: Corticotropin-releasing factor (CRF) and catecholamines are among the major hormones activated during the adaptive response to stressful stimuli. In pregnant women, serum CRF and catecholamines levels increase during labor and preterm delivery. The aim of the present study was to evaluate whether psychosocial stress measures are correlated with serum CRF or urinary catecholamine [ie, epinephrine, norepinephrine (NE), dopamine (DA)] levels in healthy midtrimester pregnant women. METHODS: A large group of white pregnant women (n = 382) participated in the present study. The Work Conditions Questionnaire and the Psychiatric Epidemiology Research Interview were administered to measure job stress and general life stress, respectively. Urine and blood specimens were collected at 28 weeks of gestation at the time of psychosocial evaluation. Epinephrine, NE, and DA were quantified in the urine by a highly sensitive method based on an amperometric detector. Serum CRF and cortisol levels were measured in blood specimens by using specific radioimmunoassays. RESULTS: Serum CRF and cortisol levels did not vary between patients with high and low scores on psychological tests, and no correlation was found between CRF and cortisol levels. One job stress measure, low job latitude, was significantly associated with a mild increase in NE and DA levels in the afternoon and night (P < .05, analysis of variance). Serum cortisol levels were inversely correlated with NE in the morning (r = -0.447; P =.002) and night segments (r = -0.391; P = .007) and with DA in the night period (r = -0.367; P = .013). CONCLUSION: The absence of a significant relationship between CRF/cortisol and psychosocial stress measures in pregnant women suggests that the hypothalamic-pituitary-adrenal response to psychosocial stress may be masked at midtrimester by the constantly high levels of placental CRF, whose control is beyond the influence of environmental stressors.

Catecholamines↗

Maternal plasma calcitonin gene-related peptide levels do not change during labor and are not influenced by delivery route.

OBJECTIVE: Calcitonin gene-related peptide (CGRP) circulates in maternal circulation throughout pregnancy, and specific receptors for CGRP (CGRPrs) are expressed by human myometrium. Because CGRP induces a dose-dependent relaxation of human myometrium, we examined a role for CGRP in modulation of myometrial smooth muscle contractility during pregnancy and labor. The aim of the present study was to evaluate the changes of maternal serum CGRP levels during parturition, according to the mode of delivery and in relation to cervical dilatation. METHODS: Circulating CGRP levels were measured in the following groups of healthy women: nonpregnant women, during the follicular phase of the menstrual cycle (n = 19); at term pregnancy (39-40 weeks; n = 24); after elective cesarean delivery (39-40 weeks; n = 20); and at spontaneous vaginal delivery (39-40 weeks; n = 16). In a subgroup of women, blood samples were collected longitudinally throughout labor at various cervical dilatations in the progress of labor (n = 8). RESULTS: Pregnant women at term not in labor had significantly higher CGRP levels than nonpregnant women (P =.021). No significant difference was found between women who delivered vaginally and those who had elective cesarean, and there were no correlations between CGRP plasma levels and cervical dilatation. CONCLUSIONS: Parturition is characterized by no significant changes in maternal serum CGRP levels, and no significant correlation exists between plasma CGRP levels and cervical dilatation during labor.

Adult↗

Immune-neuroendocrine correlations: a new aspect in human physiology.

The neural, endocrine, neuroendocrine and immune system are part of a complex network involved in the maintenance of the body homeostasis. Many experimental evidences suggest that cytokines are able to cause the hormonal changes during inflammation. The clinical evidences of the interaction between immune system and hypothalamus-pituitary-gonadal (HPG) axis are based on the sexual dimorphism existing in the immune response, the prevalence of autoimmune diseases in females and the altered immune response during pregnancy. Even if both humoral and cellular immunity are involved, the action of estradiol and progesterone is mainly exerted on mononuclear cells.

Cell Communication↗

Neurobehavioral and neurochemical abnormalities of pre- and postnatally lead-exposed rats: zinc, copper and calcium status.

Although diverging opinions have been expressed, there is a body of evidence of a cause-effect relationship between chronic exposure to lead and altered behavior in children. There are several problems in the interpretation of the behavioral and biochemical anomalies described in experimental models of lead intoxication due mainly to the different experimental conditions used. One of the major criticisms is linked with the claim that in several studies too high levels of exposure were used, hence inducing the suspicion that the effects specifically attributed to lead intoxication could be related to unspecific actions. Here we report that, using an experimental model of pre- and postnatal intoxication of rats exposed to a very low amount of lead (1 mg/kg/day), in parallel with behavioral anomalies, there are slight changes in cerebral dopaminergic and GABAergic receptors. A new finding was the discovery that in this condition there is a markedly increased number of opiate receptors in the hypothalamus (and other brain areas) in parallel with a decrease of beta-endorphin and an increase of Met-enkephalin. Therefore, low levels of lead intoxication which could be pertinent to the human situation, seem to induce neurotoxic effects which may be responsible for the behavioral anomalies in rats and, maybe, in children.

Animals↗

Functional opioid activity variates according to the different fashion of alcohol abuse.

Two groups of alcohol addicts (total of 14 subjects), were submitted to Traditional Manual Acupuncture and pituitary hormone plasma levels, including B-Endorphin (B-EP), were measured in basal condition and after 1, 5, 20 and 60 minutes from needle withdrawal. Group A patients had a polarity towards negative affective tone presenting signs of dysphoria while group B was composed of the so-called "social drinkers". No difference existed in basal hormonal values, except slightly elevated plasma B-EP levels in group A. No significant responses to TMA were recorded in plasma ACTH, Cortisol, Prolactin or GH levels in groups A and B. Social drinkers showed an increase of B-EP plasma levels in response to TMA (128 +/- 62.1%, mean +/- SD) which on the contrary was absent in dysphoric alcoholics (2.8 +/- 38.6%, p less than 0.01). The same was true for B-Lipotropin plasma levels. These preliminary results suggest that different fashions of alcohol abuse may be associated with different reactivity of the endogenous opioid system.

Acupuncture Therapy↗

[Non-specific pituitary responses in insulin-dependent diabetes mellitus in children and adolescents].

OBJECTIVES: Several reports indicate a number of changes in the control of the release of PRL, LH, FSH, GH and beta-endorphin (B-EP) as a result of insulin-dependent diabetes mellitus (IDDM). In this study we evaluate the presence of non-specific pituitary responses to releasing hormones in IDDM children and adolescents. METHODS: The non-specific effects of TRH on plasma GH, LH and B-EP levels and of GnRH on plasma GH, PRL, TSH and B-EP levels were measured in 16 IDDM children and in 16 healthy children matched by age and sex. All subjects were tested with injection of TRH (200 micrograms i.v. bolus) and GnRH (50 micrograms i.v. bolus). GH, TSH, PRL, LH and B-EP levels were evaluated with radioimmunological methods on blood samples collected before and after stimulation by releasing hormones. RESULTS: GH and B-EP non-specific responses to TRH and GnRH were significantly more pronounced in IDDM patients than in controls. All patients showed at least one non-specific response to one of the two releasing hormones. No significant correlations were found between non-specific pituitary responses and the patient's age, the duration and onset of disease or the degree of metabolic control. CONCLUSIONS: These observations may indicate that: in IDDM hypothalamus-pituitary regulating mechanism is altered; the hormones whose levels are most often found to be abnormal in IDDM (other than insulin) are also hormones which respond non specifically to the neuropeptides TRH and GnRH.

Adolescent↗

Interleukin-2 production by cultured human granulosa cells.

OBJECTIVE: To determine whether cultured human granulosa cells (GC) produce Interleukin (IL)-2 and whether this GC IL-2 production may be regulated by human chorionic gonadotropin (hCG). MATERIALS AND METHODS: Human GC derived from preovulatory follicles during in vitro fertilization (IVF) cycles were cultured in the absence or presence of hCG. Interleukin-2 was measured in tissue-culture medium by an enzyme-linked immunosorbent assay (ELISA) system. RESULTS: Cultured GCs were demonstrated to produce IL-2 in vitro. Moreover, a positive, but not statistically significant, dose-response effect was demonstrated between culture supernatant IL-2 levels and hCG concentration. CONCLUSIONS: Our data indicate that human GC produce IL-2 and that this production might be regulated by hCG. These results lend credence to the theory that IL-2 might be involved in the events leading to ovarian hyperstimulation syndrome (OHSS).

Cells, Cultured↗