Search PubMed⌕ Search

Biomedical subjects

C Carani

Publications and source records attributed to C Carani.

At least 73 records · Page 4Linked to original sources
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

An intrauterine progesterone contraceptive system (52 mg) used in pre- and peri-menopausal patients with endometrial hyperplasia.

An intrauterine progesterone contraceptive system (IPCS) (52 mg) was inserted in 25 women with cystic endometrial hyperplasia. Among these women, 11 complained of heavy climacteric symptoms and also received an oestrogen replacement therapy consisting of conjugated oestrogens (0.625 mg/day) administered cyclically for 3 out of 4 wk. Prior to the therapy and after 6 mth of treatment, follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), oestrone (E1) and oestradiol (E2) plasma levels were measured and endometrial histology was evaluated. In the women receiving IPCS treatment alone, there were no significant changes in FSH, LH, PRL, E1 and E2 plasma levels. However, there were remarkable changes found in their endometrial histology. In the remaining women receiving both treatments there was a sharp decrease in FSH and LH plasma levels and an increase in E1 and E2 plasma levels, while the prolactin levels remained unchanged. With the exception of two of these women, the endometrial histology changed remarkably. The endometrial morphology of the two exceptions remained unchanged. All climacteric symptoms disappeared after the administration of both IPCS and the oestrogen replacement therapy. The remarkable changes which did occur in the endometrial histology resulted in a less active glandular epithelium and stromal decidual formation, thus proving a useful effect of treatment.

Adult↗
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↗
PubMed1981

[Nelson's syndrome. A case report (author's transl)].

Two cases of Nelson syndrome with typical clinical and laboratory features are presented. Both had radiological evidence of pituitary tumor; in one case it was evident on the plain film while in the other one it was better appreciated by means of tomography. It is important in the post-surgery follow-up of patients who underwent bilateral adrenectomy for Cushing's disease a periodical evaluation of skin pigmentation, visual field width and sellar morphology for the early detection of a pituitary adenoma.

Adolescent↗
PubMedDate not supplied

Chronobiology of catecholamine excretion in normal and diabetic men.

The adrenomedullary response to stimuli is often elevated in poorly controlled insulin dependent diabetic patients, and it is controversial whether the adrenomedullary hyperactivity induces the suppression of the circadian rhythm of catecholamines. We have studied the urinary excretion of catecholamines in 11 diabetic patients during 48 h in 4-h collections. Eleven age and weight matched normal subjects served as controls. A circadian rhythm was detected for adrenaline and noradrenaline excretion both in normal and diabetic subjects, with the highest value for both catecholamines in the early afternoon. The mean daily adrenaline levels were significantly higher in diabetic than in control subjects (p less than 0.05). The dopamine excretion was correlated with noradrenaline excretion in normal subjects but did not show a definite circadian rhythm. We conclude that the adrenomedullary hyperactivity does not affect the rhythmic fluctuations of adrenaline and noradrenaline. The dopamine excretion does not show circadian variations and this probably reflects the absence of a single controlling oscillator.

Adrenal Medulla↗
PubMedDate not supplied

Neuropeptide Y produces anxiolytic effects in spontaneously hypertensive rats.

The sedative and anxiolytic effects of intracerebroventricular administration of neuropeptide Y (NPY) were studied in spontaneously hypertensive rats (SHR) and in normotensive Wistar-Kyoto (WKy) rats using the two-compartment exploratory test, and in the open-field test after habituation. In the two-compartment tests, NPY produced anxiolytic effects by increasing the exploratory activity in SHR at a dose (0.25 nmol) lower than the minimal effective dose in WKy rats (1.25 nmol). In SHR, anxiolytic effects were observed for the whole NPY dose range (0.25-5.0 nmol), whereas in normotensive WKy rats the highest dose (5.0 nmol) failed to increase exploratory activity. The open-field test showed reduced locomotor activity and rearings in WKy rats when injected with 5.0 nmol NPY. These effects were not observed in SHR. The absence of sedative effects and the higher sensitivity to the anxiolytic effects of NPY in SHR are suggestive of a genetically determined difference in central NPY systems involved in behavioral adaptation that may be relevant for the development of hypertension.

Animals↗
PubMedDate not supplied

Postnatal maternal separation during the stress hyporesponsive period enhances the adrenocortical response to novelty in adult rats by affecting feedback regulation in the CA1 hippocampal field.

The aim of the present experiment was to study the effects of early postnatal maternal separation on behavioural and adrenocortical responses to novelty in rats tested as adults. Sprague-Dawley rat pups were exposed to daily maternal separation (5 h/day) from postnatal day 2 to 6, during the stress hyporesponsive period. Since this procedure requires physical contact with the animals, a first control group of daily handled pups was introduced. A second control group, consisting of pups never handled or separated from the mother, was also considered. At postnatal day 45, the rats were tested in a two-compartment exploratory apparatus: the maternally separated and the non-handled rats, whose behavioural performance did not differ, showed higher emotional behaviour when compared with the handled rats (P < 0.05), suggesting that the handling procedure but not maternal separation improved the capacity to cope with novelty. Corticosterone plasma levels were found to be higher in the maternally separated rats than in the other two groups (P < 0.05), either at resting conditions or at 30 min after novelty exposure (P < 0.05). Levels of nuclear glucocorticoid receptor immunoreactivity in the CA1 hippocampal field were shown to be regulated by novelty exposure, as expected, in both the handled and the non-handled rats but not in the maternally separated rats. In conclusion, repeated maternal separation periods of 5 h/day during the first week of life produced long-lasting effects on the hippocampal regulation of the hypothalamic-pituitary-adrenocortical axis, which appear to be associated with increased responsiveness to stress stimuli in adulthood.

Adrenal Cortex↗
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↗