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Biomedical subjects

V Montanini

Publications and source records attributed to V Montanini.

26 records · Page 2Linked to original sources
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↗