Search PubMed⌕ Search

Biomedical subjects

A R Genazzani

Publications and source records attributed to A R Genazzani.

At least 19 recordsLinked to original sources
PubMed1992

Evidence of alpha-N-acetyl beta-endorphin in human cerebrospinal fluid.

Alpha-N-acetyl-beta-endorphin (Ac-beta-EP) is a post-translational product of beta-endorphin (beta-EP) with no analgesic properties. Ac beta-EP is present in human fetal and adult pituitary gland and cross-reacts in all available beta-EP assays. This study evaluates levels of Ac-beta-EP in the cerebrospinal fluid (CSF) of 22 normal subjects and 15 chronic headache sufferers. Since dopamine may play a role in the acetylation process, homovanillic acid levels were also determined. After extraction and high performance liquid chromatographic (HPLC) fractionation of CSF, an immunoreactive Ac-beta-EP peak was detected coeluting with reference peptide. Ac-beta-EP was detectable in all but 5 normal subjects. In headache sufferers, Ac-beta-EP levels were always detectable and their mean value was significantly higher than that of healthy subjects (11.6 +/- 11.8 vs 3.9 +/- 3.6 fmol/ml; P less than 0.01). Conversely, CSF beta-endorphin (beta-EP) concentrations were decreased in headache patients (9.8 +/- 9.4 vs 15.7 +/- 9.7 fmol/ml; P less than 0.05), and as a consequence the beta-EP/Ac-beta-EP ratio was also markedly reduced (P less than 0.005). No difference was observed for CSF homovanillic acid concentrations. These data demonstrate that HPLC coupled to radioimmunoassay allows the identification of low but significant amounts of Ac beta-EP in human CSF. This compound represents a confounding factor when beta-EP immunoreactivity is assessed by conventional methods. In headache sufferers, Ac-beta-EP levels were higher than normal, whereas beta-EP concentrations were lower.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Effect of naltrexone treatment on the treadmill exercise-induced hormone release in amenorrheic women.

The effect of an acute physical stress on hormone secretions before and after a 10-day naltrexone treatment in untrained healthy and amenorrheic women was investigated. Plasma levels of pituitary (LH, FSH, prolactin, GH, ACTH, beta-endorphin) and adrenal (cortisol, androstenedione, testosterone) hormones were measured at rest and in response to 60 min of physical exercise. The test was done both before and after a 10-day naltrexone (50 mg/day) treatment. Graded levels of treadmill exercise (50, 70 and 90% of maximal oxygen uptake (VO2) every 20 min) was used as physical stressor. While mean +/- SE plasma LH levels in control women were higher than in amenorrheic patients and increased following the naltrexone treatment (p < 0.01), no significant differences of basal plasma hormonal levels were observed between amenorrheic and eumenorrheic women, both before and after naltrexone treatment. Physical exercise at 90% VO2 induced a significant increase in plasma GH, ACTH, beta-endorphin, cortisol, androstenedione and testosterone levels in controls before naltrexone treatment (p < 0.01). The mean increase in plasma androstenedione and testosterone levels in control women was significantly higher after naltrexone treatment (p < 0.01). In amenorrheic patients before naltrexone, physical exercise induced an increase in plasma prolactin and GH levels, but not in plasma ACTH, beta-endorphin, cortisol, testosterone and androstenedione. After naltrexone treatment, the exercise induced a significant plasma ACTH, beta-endorphin and cortisol levels, while the increase of plasma prolactin levels was significantly higher than before treatment (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Ovarian opioids and the reproductive cycle of the frog Rana esculenta.

In mammals, proopiomelanocortin-related peptides are involved in reproductive processes both at the hypothalamo-pituitary and ovarian levels. Using immunocytochemical, biochemical and physiological "in vitro" studies, we provide here evidence for a diffuse POMC-related opioid system in the frog Rana esculenta. Ovarian beta-endorphin (beta-EP) is expressed in thecal cells and changes during the reproductive cycle in an inverse relationship with follicular development. Seasonal changes in the ovary are different to those in the brain or in the pituitary. The ratio of acetylated vs native beta-EP in the ovary also changes over the reproductive period, affecting the biological activity of the peptide. During both the reproductive spring period and the summer post-reproductive phase pMol amounts of beta-EP stimulate follicular androgen secretion in vitro, in a naloxone-reversible way. In either period, an inhibition of estradiol, possibly mediated via other factors, is the result of opioid action. In conclusion, these data demonstrate for the first time the widespread presence of beta-EP-related peptides in the frog Rana esculenta. Both immunocytochemical and biochemical evidence, as well as in vitro responses, support a physiological role for beta-EP in ovarian seasonality during the reproductive cycle of this amphibian.

Amino Acid Sequence↗
PubMed1992

Central changes of beta-endorphin-like immunoreactivity during rat tonic pain differ from those of purified beta-endorphin.

Several studies have described changes in beta-endorphin-like immunoreactivity (beta-ELI) in the rat brain in response to pain and stress stimuli. In order to ascertain the components of beta-ELI, brain samples of rats experiencing acute prolonged (tonic) pain were evaluated for their beta-ELI and later submitted to a chromatographic purification allowing the measurement of beta-endorphin (beta-EP) and acetyl beta-EP. The chromatographic analysis of both ventromedial hypothalamus (VMH) and periaqueductal grey (PAG) homogenates indicates that beta-ELI is distributed in several fractions including shortened forms of beta-EP and their respective acetylated compounds. Quantitatively, while beta-ELI in formalin-injected animals was increased by 48% in VMH and 45% in PAG in respect to controls, the net increase of purified beta-EP was 1100% and 470%, respectively, for VMH and PAG. Moreover, the maximal increase of beta-ELI was evident at 120 min, in both tissues. In contrast, the beta-EP peak was reached at 30 min in VMH and at 60 min in PAG. Acetyl beta-EP was unchanged by treatment in both central areas. No correlation of beta-ELI and beta-EP was found in VMH. These data demonstrate that the evaluation of beta-ELI gives a poor estimate of beta-EP changes, due to several components of the endorphin family.

Animals↗
PubMed1992

The brain as a target organ of gonadal steroids.

Gonadal steroids have many effects in the central nervous system. Through a feedback mechanism, they influence the synthesis and release of hypothalamic gonadotropin-releasing hormone (GnRH) and/or pituitary gonadotropic hormones (luteinizing hormone, LH, and follicle stimulating hormone, FSH). Endogenous opioid peptides (EOPs) represent one of the key factors modulating the activity of sex steroids on the hypothalamus-pituitary-gonadal (HPG) axis. In particular, these peptides control the secretion of LH by inhibiting the activity of the hypothalamic neurons which produce GnRH. The EOP effect is dependent on the steroid hormone milieu, as shown by different responses to naloxone administration, both in animals and in humans. For the naloxone-induced increase in LH secretion to occur, relatively high levels of sex steroids are required. In humans, LH release is absent before sexual maturation. In fertile women, naloxone administration increases LH levels in the luteal phase but not in the follicular phase. In the postmenopausal period, naloxone has no effect on LH release; estrogen/progestin therapy does restore the LH response.

Aging↗
PubMed1992

Maternal hyperoxygenation in the treatment of intrauterine growth retardation.

OBJECTIVE: In the current study the efficacy of maternal hyperoxygenation on growth-retarded fetuses was evaluated. STUDY DESIGN: Thirty-six pregnant women with intrauterine growth retardation were studied. The patients were divided in oxygen-treated (n = 17) and untreated (n = 19) groups. Doppler analysis of the fetal circulation was performed on the arrival to the hospital, after 12 hours, and thereafter on alternate days until delivery. Fetal blood was sampled by cordocentesis for immediate blood gas analysis at entrance to the study and the day of delivery. RESULTS: Significant improvement in Doppler flow patterns in treated patients were found when compared with untreated women. The Doppler variations were associated with complementary modifications in fetal blood gas. These differences resulted in a significant modification in perinatal mortality with an incidence of 29% and 68% (p less than 0.01) in treated and untreated groups, respectively. CONCLUSION: Our data suggest a benefit of maternal hyperoxygenation in the treatment of fetal growth retardation.

Arteries↗
PubMed1992

Studies on direct intraperitoneal insemination in the management of male factor, cervical factor, unexplained and immunological infertility.

One-hundred-and-twenty couples with male factor, cervical factor, unexplained or immunological infertility underwent direct intraperitoneal insemination (DIPI) of capacitated spermatozoa, combined with ovarian stimulation for a total of 254 cycles. Pregnancy occurred in 47 cycles, resulting in an overall pregnancy rate of 40.5% per patient (two pregnancies occurred in two patients) and a cycle fecundity of 18.5%. Of the patients, 23 have delivered live infants (one twins, 22 singletons), 15 (32%) miscarried and 9 have ongoing pregnancies. The cycle fecundity rates increased with increasing sperm concentration and total progressive motile count, both before and after sperm preparation (r = 0.8161, r = 0.8717 and r = 0.759, r = 0.795, respectively). However, there were two pregnancies where the inseminates had a count of 0.1 x 10(6) total motile spermatozoa. DIPI as an outpatient, in-vivo conception procedure offers encouraging results and is recommended before attempting more costly and invasive assisted reproduction techniques.

Female↗
PubMed1992

Effects of growth hormone administration in addition to gonadotrophins in normally ovulating women and polycystic ovary syndrome (PCO) patients.

Follicular fluid sex-steroids, insulin-like growth factor-I (IGF-I), IGF-I binding protein (IGF-I-BP) and epidermal growth factor were investigated in patients with polycystic ovaries and normally ovulating women, following ovulation induction with gonadotrophins or growth hormone plus gonadotrophins. Growth hormone supplementation enhanced the ovarian response to gonadotrophins, and significantly increased follicular fluid IGF-I in both groups, without affecting follicular fluid epidermal growth factor; growth hormone supplementation significantly decreased follicular fluid androstenedione in both groups.

Adult↗
PubMed1992

Melatonin treatment delays reproductive aging of female rat via the opiatergic system.

In female rat age-related reproductive decline is accompanied by progressive impairment of the neuroendocrine mechanisms that regulate LH secretion. The biosynthetic activity of the pineal gland is markedly depressed and the nocturnal secretion of melatonin decreases significantly. The aim of the present study was to evaluate whether the nocturnal administration of melatonin via the drinking water (0.4 micrograms/ml) throughout the course of aging from 14 to 24 months of age could (1) influence the age-related changes that occur in basal serum levels of LH and in the LH response to GnRH or to naloxone stimulation at 16, 18 and 20 months of age, and (2) delay the onset of the postreproductive constant estrous-anovulatory state as evaluated by the daily recording of vaginal smears and by occurrence of polyfollicular ovaries at 24 months of age. Our results demonstrate that melatonin replacement delays the increase in LH serum levels and the decrease in LH response to GnRH that occur in 18-month-old control animals. Furthermore, they show that melatonin treatment prevents the loss of LH response to naloxone manifested in control rats between 16 and 20 months of age. Melatonin also appears to prevent the progressive increase in the monthly occurrence of estrus phases as well as to decrease the number of rats with polyfollicular ovaries at 24 months of age in comparison to control animals. These results suggest that the age-related decrease in circulating melatonin during the night may contribute to the reproductive decline of aging, and that this effect may involve the central opioid system.

Aging↗
PubMed1992

Psychosomatic disorders related to gynecology.

In this paper current issues on four psychosomatic disorders related to gynecology will be reviewed. The history, nosological problems and psychoneuroendocrine correlates of psychogenic amenorrhea have been summarized taking into account the important role of psychological factors in inducing loss of menses. Definition and diagnostic problems in assessing menstrually related disorders (formerly premenstrual syndrome) have been reviewed, looking at this syndrome as a disorder of adaptation to the cyclical changes of neuroendocrine functions. The impact of stress on fertility and, on the other hand, the effects of infertility on psychological well-being have been pointed out trying to ascertain the pathways involved in these mutual relationships. Finally, the issue of mood changes at menopause and the effects of steroid replacement on affective state have been discussed. As a whole, these evidences indicate the importance of a close cooperation between gynecologist and psychiatrist in the management of gynecological disorders.

Adolescent↗
PubMed1992

Gonadotropin-releasing hormone, inhibin, and activin in human placenta: evidence for a common cellular localization.

The human placenta produces several hypophysiotropic factors that participate in the control of local hormone secretion. In particular, previous reports showed that inhibin and activin modulate both GnRH release and hormonal effect in cultured human placental cells. The present study evaluated the possible correlations among the synthesis and cellular distribution of inhibin, activin, and GnRH in placental villi at term. mRNA coding for inhibin alpha- and beta A-subunits and GnRH were localized in human placenta at term by in situ hybridization using the corresponding cDNA probes. Autoradiograms revealed that some placental cells express inhibin alpha- and beta A-subunit and GnRH mRNAs. A common localization of the three hormonal mRNAs has been found in the inner part of the villi. Using affinity-purified polyclonal antisera, immunocytochemical studies confirmed that in placental villi at term, immunoreactive inhibin alpha- and beta A-subunits and GnRH had a distribution that was superimposable in several areas. Both the outer layer and the inner trophoblasts contained immunoreactive hormonal products. The present data show that some placental cells at term can produce and release inhibin, activin, and/or GnRH. This complement of hypophysiotropic factors may, thus, represent a local paracrine/autocrine control mechanism within the placenta.

Activins↗
PubMed1992

Human decidua and in vitro decidualized endometrial stromal cells at term contain immunoreactive corticotropin-releasing factor (CRF) and CRF messenger ribonucleic acid.

CRF, a hypothalamic neurohormone, has been shown to be present in several tissues outside the brain. During pregnancy, both fetal (placental trophoblast, chorion, and amnion) and maternal (decidua) intrauterine tissues contain immunoreactive CRF. A paracrine/autocrine role of CRF as a regulator of hormonogenesis in human placenta and decidua has been suggested. The expression of CRF mRNA in human decidua was demonstrated in the present study by Northern blot analysis and was found to be higher in specimens collected at term than in those collected during the first and second trimesters of gestation. Furthermore, the presence of CRF was detected immunocytochemically in cultured decidual cells isolated from term decidua as well as in endometrial stromal cells decidualized in vitro by treatment with a mixture of medroxyprogesterone acetate, estradiol, and relaxin. These results indicate that human decidua is an intrauterine extrahypothalamic source of CRF in the maternal compartment and offer new tools to explore the in vitro decidualization processes and the regulation of CRF release from decidual cells.

Abortion, Spontaneous↗
PubMed1992

Acute beta-interferon or thymopentin administration increases plasma growth hormone and cortisol levels in children.

The interaction between the immune and endocrine systems has recently been investigated. Hodgkin's disease represents a model of immune disturbance frequently associated with endocrine impairment. The present study evaluated the effect of the acute administration of beta-interferon or thymopentin on plasma growth hormone, prolactin and cortisol levels in children with Hodgkin's disease (N = 8) and age- and sex-matched healthy controls (N = 8). beta-interferon (1,000,000 IU), thymopentin (50 mg) or placebo (saline) were injected after two basal blood samples (-15 and 0) and further samples were drawn at 15, 30, 45, 60, 90 and 120 min. Plasma growth hormone, prolactin and cortisol levels were measured by specific RIAs. Plasma prolactin levels did not show significant change following beta-interferon or thymopentin injection in either the controls or the patients. In the patients with Hodgkin's disease, beta-interferon injection induced a significant increase in both plasma growth hormone and cortisol levels, while thymopentin was not effective. In controls both thymopentin and beta-interferon administration increased plasma growth hormone and cortisol levels. These results indicate that beta-interferon and thymopentin are immune substances active on the release of growth hormone and cortisol in healthy children. The lack of effect of thymopentin in children with Hodgkin's disease suggests an impairment of the immune-endocrine interaction in these patients.

Adolescent↗
PubMed1992

Oral magnesium supplementation improves fetal circulation.

It is well known that pregnancy is a condition in which plasma magnesium falls because of accumulation of the ion in the placenta and fetus. Magnesium (Mg) is therefore widely given as a supplement during pregnancy, particularly in cases of preterm labour. In our experience, the combination of oral Mg (magnesium pyrrolidone carboxylic acid) at a dose of 360 mg/day with conventional ritodrine treatment allows a reduction in ritodrine dosage, accompanied by a significant reduction in side effects. We therefore evaluated changes in fetal blood flow, using pulsed Doppler, in women submitted to combined magnesium and ritodrine treatment compared to those treated with ritodrine plus placebo. The Mg-treated group showed a decrease in vessel resistance both in the umbilical artery and in the fetal middle cerebral artery, indicating that fetal vasculature is sensitive to exogenous Mg. Measurement of plasma and mononuclear cell Mg showed an intracellular increase in the cation of about 10 per cent. We conclude that oral magnesium supplementation in pregnancy is safe and that it has a positive effect on the fetal circulation.

Cerebral Arteries↗
PubMed1992

Sperm retrieval for direct intraperitoneal insemination in a diabetic with retrograde ejaculation. A case report.

Retrograde ejaculation is an uncommon form of male infertility. It may occur in diabetics from neuropathy involving the sympathetic fibers innervating the bladder neck. Treatment of infertility in these cases is with artificial homologous insemination. Several techniques for semen recovery from the bladder have been proposed. This paper describes a case of twin pregnancy following direct intraperitoneal insemination (DIPI) of semen retrieved from a diabetic man with retrograde ejaculation. Retrieval of semen was performed in this case by spontaneous voiding of urine after the introduction of a suitable medium into the bladder and before ejaculation. The quality of the semen was examined after spontaneous urination before DIPI. The poor quality of the spermatozoa induced us to introduce into the bladder a suitable medium before ejaculation and sperm recovery.

Administration, Intravesical↗
PubMed1991

Follicular fluid steroid and epidermal growth factor content, and in vitro estrogen release by granulosa-luteal cells from patients with polycystic ovaries in an IVF/ET program.

The follicular fluid (FF) content of androgens, estrogens and epidermal growth factor (EGF) has been evaluated in a group of patients with policystic ovary disease (PCO) and in one of normally-ovulating infertile women (NOW) in an IVF/ET program. The in vitro response to follicle-stimulating hormone (FSH) has been also evaluated in granulosa luteal cells from the same patients. PCO patients showed significantly higher FF androstenedione (delta 4) and testosterone (T) and similar FF estrone (E1) and 17 beta-estradiol (E2) levels compared to controls. In vitro production of E1 and E2 by granulosa luteal cells from PCO patients and from controls were overlapping and their response to FSH was similar. These data indicate a normal intrinsic potential aromatase activity in ovaries from PCO patients stimulated with gonadotropins and suggest that PCOs do not derive from inherent ovarian aromatase deficiency. Increased FF androgen content following gonadotropin stimulation may result from theca cell hyperactivity and androgen accumulation in the follicular antrum of rescued hyperandrogenic follicles as well as from inhibitory factors that may inhibit aromatase activation in vivo, partially counteracting the effect of gonadotropins. FF EGF levels were significantly higher in the group of PCO patients compared to those of NOW. EGF may play a role in blunting the in vivo response of granulosa cells to gonadotropins.

Androstenedione↗
PubMed1991

Reduced spinal bone density in young women with amenorrhoea.

To assess the influence of diminished oestrogen production on bone density, we studied 23 amenorrhoeic women and 20 controls (age range 16-29 years) divided into four groups: group 1: 6 patients with idopathic hypogonadotrophic hypogonadism with primary amenorrhoea (IHH); group 2: 5 patients with delayed puberty owing to thalassaemia major (TM); group 3: 12 patients with secondary hypothalamic amenorrhoea (HA); group 4: 20 women with normal menses (controls). Secondary sexual characteristics had developed in all except the women with TM. Groups 1 and 2 had never menstruated and group 3 had been amenorrhoeic for 6 months to 3 years. The control group was studied during the follicular phase of the cycle. None of the patients were taking oestrogens at the time of observation. Plasma concentrations were determined for 17 beta-oestradiol (E2), deidroepiandrosterone sulphate (DHEA-S), cortisol (F), prolactin (PRL), thyroid hormones (T3 and T4), and gonadotrophins (LH and FSH). Spinal bone mineral density (BMD g/cm2) was assessed by dual photon absorbiometry. BMD (mean +/- 1SD) was reduced in the patients (group 2: 0.920 +/- 0.95; group 1: 0.980 +/- 0.94; and group 3: 1.037 +/- 0.75) as compared with the controls (1.290 +/- 0.95) (P less than 0.01). In the three groups of patients, plasma E2 levels were lower than 50 pg/ml and were positively correlated with the BMD. As expected, plasma gonadotrophin levels were highly and significantly reduced (P less than 0.01) in the patients, compared with that of the controls. These results suggest that reduced spinal BMD in hypogonadic women may be related to the lack of oestrogenic influence on bone metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗