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Biomedical subjects

G F Baraghini

Publications and source records attributed to G F Baraghini.

17 recordsLinked to original sources
PubMed1990

Estimation of instantaneous secretory rate of luteinizing hormone in women during the menstrual cycle and in men.

In both men and women the pulsatile secretory pattern of LH has been extensively characterized. In the present study we used the algorithm for computation of instantaneous secretory rate (ISR) incorporated into the DETECT program to evaluate the secretory activity of gonadotrophs in vivo. We studied the pulsatile release of LH in four healthy women during four phases of the same menstrual cycle (early and late follicular and luteal phases) and in five healthy men. Computation of ISR permitted us to estimate the frequency and the duration of the secretory events from the gonadotrophs. Samples were collected every 10 min for 6 h. The apparent LH pulsatile frequency during the menstrual cycle varied from 5.0 +/- 0.8 (mean +/- SD) during the early follicular phase (EFP) to 5.3 +/- 1.2 peaks/6h during the late follicular phase (LFP), to 3.3 +/- 1.0 during early luteal phase (ELP) and to 5.3 +/- 0.4 peaks/6h during the late luteal phase (LLP). The mean pulse duration also changed throughout the phases of the cycle (EFP 47.4 +/- 13.2 min; LFP 55.4 +/- 21.6 min; ELP 100 +/- 50.4 min; LLP 48.1 +/- 11 min). In healthy men the LH pulse frequency was 3.8 +/- 1.6 peaks/6h and the duration was 71.5 +/- 35.7 min. When time series were analysed for ISR determination no significant changes were observed between the LH pulse frequency detected on ISR and that observed on plasma concentrations. Conversely, a significant reduction of the duration of the pulses was found when using ISR instead of plasma concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Age-related changes in plasma dehydroepiandrosterone sulphate, cortisol, testosterone and free testosterone circadian rhythms in adult men.

The circadian rhythms of serum luteinizing hormone, follicle-stimulating hormone, testosterone (T), free testosterone (fT), sex hormone-binding globulin (SHBG), oestradiol, cortisol and dehydroepiandrosterone sulphate (DHA-s) have been investigated in 5 normal male adults and 6 elderly men. Circadian rhythms were detected statistically significant (p less than 0.05) by population mean cosinor analysis, for T, fT, cortisol and DHA-s in the young group. In the elderly population, serum cortisol showed a clear circadian rhythm, although with some phase modification, whereas DHA-s secretion lost its circadian rhythmicity. This demonstrates that ageing differently affects the two major adrenal functions, glucocorticoid and androgenic; further, the data suggest that an independent adrenal androgen-regulating system could be selectively impaired in the older subjects. In the elderly group the loss of T circadian rhythm was confirmed, but a statistically significant circadian rhythm of fT was recorded. It was characterized by a marked phase advance and not related with the SHBG modifications found in elderly men. This finding leads us to reconsider the role of fT, which appears more sensitive than total T, in studying circadian rhythm of gonadal androgen secretion.

Adult↗
PubMed1984

Effects of acute stimulation with gonadotropin releasing hormone (GnRH) on biologically active serum luteinizing hormone (LH) in elderly men.

This study was designed to characterize the response pattern of biologically active LH (BIO-LH) after Gonadotropin Releasing Hormone (GnRH) acute administration in healthy elderly men, in comparison with normal young adult men. Serum levels of BIO-LH under basal conditions and in response to the iv injection of 0.1 mg synthetic GnRH were measured in 6 healthy elderly men (mean age 74.2 yr), as well as in 9 normal young men (mean age 27.4 yr). A sensitive in vitro bioassay, based upon testosterone production by mechanically dispersed mouse Leydig cells, was employed to assess LH biological activity. Levels of immunoreactive LH (RIA-LH) and basal testosterone (T) concentrations were determined by a double antibody radioimmunoassay technique. Mean basal levels of BIO-LH and RIA-LH were significantly increased in elderly men, compared to levels in young men, whereas the mean basal ratio of LH in vitro bioactivity to LH immunoreactivity (LH B/I ratio) and mean basal T concentrations were significantly lower in the elderly group. After GnRH administration, the B/I ratio of serum LH remained unchanged both in elderly and in young men. The mean relative maximum response for BIO-LH (BIO-LH delta %) was significantly lower in elderly men than in the younger male subjects, whereas mean BIO-LH response areas (BIO-LH delta areas) were not significantly different in the two groups. The mean peak response for both BIO-LH and RIA-LH was observed at 45 min in the elderly group and at 30 min in the younger subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Sexual behavior of male rats: influence of short- and long-term adrenalectomy.

Adult male rats (3 months old) were tested for their copulatory behavior: those satisfying the criterion of sexual vigor in the last three out of five weekly tests were randomly divided into two groups and adrenalectomized or sham operated, and their copulatory activity was retested 35 and 420 days after surgery. Short-term adrenalectomy did not modify any of the parameters of sexual behavior. On the other hand, a higher percentage of adrenalectomized than of sham-operated rats still had successful sexual performance when 18 months old (420 days after surgery); moreover, blood levels of testosterone were higher in adrenalectomized than in sham-operated old rats. The possibility that adrenal steroids may play a role in the age-linked decline in male sexual activity in mammals is discussed.

Adrenal Glands↗
PubMed1984

Decrease in luteinizing hormone biological activity/immunoreactivity ratio in elderly men.

Basal serum concentrations of biologically active luteinizing hormone (BIO-LH), immunoreactive LH (RIA-LH) and testosterone (T), as well as the LH bioactivity/immunoreactivity (B/I) ratios were measured in 57 healthy, elderly male volunteers aged 60-94 yr. As a reference group, 53 healthy young men aged 18-49 yr were also studied. LH biological activity was assessed by an in vitro bioassay method based on testosterone production by mechanically dispersed mouse Leydig cell preparations in response to graded doses of LH. The mean BIO-LH and RIA-LH serum concentrations in the elderly men showed a significant increase (two- and three-fold, respectively, P less than 0.001, as compared with the values in the young men, whereas the mean LH B/I ratio and T values were significantly decreased (-22% and -43%, respectively, P less than 0.001). The decrease in the LH B/I ratio in elderly men led us to hypothesize that the ageing pituitary may secrete molecules of LH possessing a reduced bioactivity in relation to their immunoreactivity.

Adult↗
PubMed1984

Further studies on the effects of heroin addiction on the hypothalamic-pituitary-gonadal function in man.

The effects of chronic heroin addiction on LH biological and immunological activity, as well as on total and free testosterone concentrations, were investigated in 8 active young male addicts. The results were compared with those obtained in 33 normal young men. In addition, the effects of naloxone (N) administration on LH bio- and immuno-potency were studied in 3 normal men. LH biological activity (bLH) was assessed by a specific and sensitive "in vitro" bioassay, based upon testosterone production by mechanically dispersed mouse Leydig cell preparations. Double antibody radioimmunoassay methods were employed to assess serum levels of immunoreactive LH (iLH), total testosterone (T) and morphine (M). Free testosterone (FT) concentrations were determined by RIA after an ultrafiltration procedure. Mean basal values of bLH, iLH, T and LH bio/immuno (b/i) ratio observed in heroin addicts were similar to those obtained in the control group. In contrast, serum levels of FT and the mean FT/T ratio were significantly reduced in heroin addicts. A significant decrease of LH b/i ratio was observed during N infusion in the normal subjects.

Adolescent↗
PubMed1984

Effects of acute stimulation with luteinizing hormone-releasing hormone (LRH) on biologically active and immunoreactive serum luteinizing hormone (LH) in pubertal boys.

The responses of biologically active LH (BIO-LH) and immunoreactive LH (RIA-LH) to acute stimulation with LRH (0.1 mg iv) were studied in 8 pubertal boys (9-15 years, 2nd-4th Tanner's stage), and in 10 healthy adult men (20-46 years). Serum levels of BIO-LH were assessed by an in vitro bioassay method based upon testosterone production by mechanically dispersed mouse Leydig cell preparations. In pubertal boys the mean BIO-LH/RIA-LH (B/I) ratio of basally secreted LH was significantly lower than in adult men (1.2 +/- 0.2 (SEM) and 2.2 +/- 0.2 respectively, P less than 0.01). After acute administration of LRH the mean B/I ratio of circulating LH showed a significant increase from the basal value in pubertal boys (2.6 +/- 0.2, P less than 0.01 vs basal values), whereas no significant difference in LH B/I ratios were demonstrated throughout the study period in adult men (2.1 +/- 0.1, P = NS vs basal values). In agreement with this finding, the mean relative maximum response for BIO-LH (BIO-LH delta %) was higher in pubertal boys than in adult men (1702.7 +/- 500.3 and 499.6 +/- 65.4% respectively, P less than 0.05), whereas the mean RIA-LH delta % was similar in both groups (609.1 +/- 85.1 and 534.1 +/- 75.5% respectively, P = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

Age and sex related variations in biologically active and immunoreactive serum luteinizing hormone.

Relatively recent data from the literature show some discrepancies between bioactive LH (Bio-LH) and radioimmunoreactive LH (Ria-LH) in different endocrinological conditions. In 202 subjects of both sexes we have studied biologically active and immunoreactive LH and their ratio (B/l ratio) pattern through life. The results show that in male puberty the in vitro bioassay method gives a more discriminating measurement of serum LH than the radioimmunoassay. The ratio between bioactive and immunoreactive LH is well correlated with the increase of serum testosterone levels from male prepuberty to adulthood. On the contrary, there is no difference of B/l ratio between prepubertal girls and fertile women, in spite of the different gonadotropin levels. Finally LH bioactivity increases less markedly in elderly men than in postmenopausal women. These data suggest that, among several factors which may influence not only the quantity but also the quality of LH secreted, gonadotropin secretion rate and sex steroid milieu play an important role and may partly explain the B/l ratio changes in the situations investigated.

Adolescent↗
PubMed1982

Circadian rhythm of testosterone and prolactin in the ageing.

The role which testicular hormones have on the decrease of sexual function in ageing men is still uncertain, but of primary interest. Previously, it has been known that the impairment of Leydig cell activity is a causal factor in the decreasing sexual function in ageing men. The present study is an evaluation of some chronobiological aspects, which directly or indirectly concern the 'Gonadostat' in ageing men, in order to determine of any change of the hypothalamic-pituitary axis occurs during the ageing process. The results from a group of 18 young men aged between 21 and 37 were compared with the results from a group of 28 older men between the ages of 67 and 98. The daily variations of testosterone (T) levels were determined in both groups of men as its circadian rhythm is well known in adult men. Moreover, the nocturnal secretory pattern of prolactin (PRL) was studied in 6 of the 28 elderly men. When comparing the usual increase of T levels in adult men, which occurs in the morning, there were no significant differences found in the older group of men between early morning and evening. The PRL levels showed no nocturnal increase in 4 of the 6 men. A hormonal impairment in the central nervous system may, in fact, be associated with the testicular deficiency leading to the decrease in sexual function of ageing men.

Adult↗
PubMedDate not supplied

Further studies on the effects of pentoxifylline on sperm count and sperm motility in patients with idiopathic oligo-asthenozoospermia.

To further investigate the effectiveness of pentoxifylline (trental) treatment in male infertility, we studied 22 young men (mean age 28.4 years) with "idiopathic" oligo-asthenozoospermia treated for 6 months with the drug (1200 mg daily orally). Sperm concentration and sperm motility were determined before therapy, as well as after 3 and 6 months of pentoxifylline administration. Moreover, fructose concentrations in seminal fluid and sperm ATP levels were assayed before and at the end of the treatment in five semen samples. Pentoxifylline therapy significantly increased both sperm concentration and sperm motility. Sperm concentration showed a 1.5-fold increase (p less than 0.01) at the 3rd month of therapy, and a 2.0-fold increase (p less than 0.001) at the 6th month, whereas sperm motility increased by 1.8-fold (p less than 0.001) and by 2.8-fold (p less than 0.001) respectively. At the end of the treatment, fructose concentrations in seminal fluid were significantly higher (p less than 0.001) than pretreatment values; in contrast, sperm ATP levels showed a significant (p less than 0.05) fall. These results suggest that pentoxifylline, probably acting on the cAMP metabolism, may be an useful drug in the treatment of idiopathic oligo-asthenozoospermia.

Adenosine Triphosphate↗
PubMedDate not supplied

Biologically active luteinizing hormone (LH) in Klinefelter's syndrome: response to gonadotropin-releasing hormone (GnRH) and effects of testosterone undecanoate.

Basal and gonadotropin-releasing hormone (GnRH)-stimulated levels of biologically active and immunoreactive LH (bLH and iLH) were measured in six patients with Klinefelter's syndrome (KS) (mean age 24.7 years). In the same patients the diurnal rhythm of serum testosterone (T) was investigated (morning values vs. evening values). The results were compared with those obtained in ten normal young men (mean age 29.3 years). Moreover, in one patient with KS we studied the effects of testosterone undecanoate (TU) administration on bLH and iLH basal levels. A sensitive "in vitro" bioassay, based on T production by mechanically dispersed mouse Leydig cells, was employed to assess LH bioactivity. Levels of iLH and T were determined by a double antibody radio-immunoassay technique. Mean basal levels of bLH and iLH were significantly higher (p less than 0.001) in the Klinefelter patients than in normal men, whereas the mean bioactivity to immunoreactivity (b/i) ratio of LH was similar in the two groups. The mean morning T concentration was significantly higher in normal men (p less than 0.001) than in the Klinefelter group. The diurnal T rhythm was lost in the patients with KS. In the Klinefelter patients the relative maximum response of bLH to GnRH (bLH delta%) was significantly lower (p less than 0.02) than in the control men. In addition, the b/i ratio of GnRH-stimulated Lh decreased significantly (p less than 0.05) from basal values in the Klinefelter patients, whereas it remained unchanged in the control group. In the patient with KS treated with androgen replacement therapy, TU decreased iLH serum levels more than bLH concentrations, thereby increasing the b/i ratio of basally secreted LH.

Adolescent↗
PubMedDate not supplied

ACTH 1-17 effects in psychogenic impotence.

The purpose of this study was to investigate the effects of repeated administrations of ACTH 1-17 (Syncrodyn 1-17) on sexual and endocrine function in men with psychogenic impotence. Twenty adult impotent men from 21 to 48 years volunteered for this study; organic causes of erectile impotence were excluded in each subject. Ten subjects were treated with ACTH 1-17 (100 micrograms i.m. daily for 15 days during 6 consecutive months), whereas saline was injected in the control group (10 subjects) following the same protocol. Clinical and endocrine evaluation were performed before and at the end of treatment. Serum levels of LH, FSH, PRL, testosterone (T) and cortisol were measured by RIA methods. To investigate diurnal rhythms of T and cortisol, blood samples were taken at 0800 and at 1800. In ACTH 1-17-treated men a significant improvement in sexual function was shown when compared with the control group (p less than 0.05); moreover, both anxiety and fatigability were lowered by ACTH 1-17 administration. ACTH 1-17 did not affect basal levels of LH, FSH, PRL, T and cortisol, whereas the diurnal variation of T, which was absent before treatment in both treated and control group, was restored. No changes in clinical and endocrine parameters were shown after placebo injections. Our data emphasize that the chronopharmacological action of ACTH 1-17 may positively affect sexual function and circadian T rhythmicity in men with psychogenic impotence.

Adrenocorticotropic Hormone↗