Search PubMed⌕ Search

Biomedical subjects

M Luisi

Publications and source records attributed to M Luisi.

At least 55 records · Page 3Linked to original sources
PubMed1989

Effects of fenfluramine and ritanserin on prolactin response to insulin-induced hypoglycemia in obese patients: evidence for failure of the serotoninergic system.

In order to study the hypothesized impairment of the serotoninergic system in human obesity, an insulin tolerance test (ITT) was carried out on 12 obese normoprolactinemic women and on 6 normal-weight women before (A) and after (B) the administration of a serotoninergic drug, fenfluramine (60 mg twice a day per os for 7 days). After a washout period, a new ITT (C) followed the administration of fenfluramine at the same dose, associated with a specific S2 blocker receptor agent, ritanserin (30 mg/day for the first 2 days and 20 mg/day for a further 5 days). In obese subjects, the prolactin (PRL) response to ITT A was reduced as compared to the controls: in 6 patients ('nonresponders') the PRL levels did not change, while in the other 6 ('responders') they increased (p less than 0.003) but less than in the controls (p less than 0.02). In normal-weight subjects, the administration of fenfluramine alone or with ritanserin did not modify the PRL response to ITT. In the responders, the serotoninergic drug normalized the PRL response to ITT while significantly improving it in the nonresponders; these effects were not antagonized by ritanserin. In conclusion, our data suggest that the serotoninergic system of obese patients is impaired and that the different secretory pattern observed in the two groups before and after fenfluramine may reflect differing degrees of this impairment.

Adolescent↗
PubMed1988

Paired study of the dorsal cutaneous ulnar and superficial radial sensory nerves.

Nerve conduction studies of the dorsal cutaneous ulnar nerve (DCU) have been suggested as a useful technique for identifying distal ulnar nerve lesions. In this study a standardized method was used to establish normal conduction parameters of the DCU that were compared to conduction parameters of the superficial radial sensory nerve (SR) in the same extremity. Fifty-five extremities of 33 neurologically healthy subjects aged 22 to 69 years (mean = 37; SD = 13) were examined. Dorsal hand skin temperature of each subject was 31 to 36 C. The DCU and SR were antidromically stimulated 14cm proximal to plastic-mounted bipolar electrodes placed on the dorsum of the hand over each nerve. Latency to onset, latency to peak, and amplitude (mean +/- 2SD) for the DCU were 2.2 +/- 0.3msec, 2.8 +/- 0.5msec, and 24 +/- 17 microV; and for the SR were 2.2 +/- 0.3msec, 2.8 +/- 0.3msec, and 32 +/- 18 microV, respectively. Significant correlations (p less than 0.005) were found between the DCU and SR latencies to onset, and DCU and SR latencies to peak. These results suggest that distal sensory latencies of the DCU and SR are similar, and that a paired study of these nerves may be useful in distinguishing distal ulnar nerve entrapment syndromes when routine studies are equivocal.

Adult↗
PubMed1987

Prolactin unresponsiveness to repeated sulpiride administration in man: recent findings.

The mechanism of prolactin (PRL) unresponsiveness to repeated sulpiride (SUL) administration was investigated by means of two experimental protocols. The first one was carried on in seven male volunteers (age 24 to 34 yr) and consisted of two phases separated by a 5-day interval. In both phases 1 mg/kg of SUL was given im and repeated, 24 h later, together with either placebo (PL, 2 ml saline iv) or TRH (200 micrograms iv). 7-10 days later a standard TRH test (200 micrograms iv) was performed. In the second protocol the usual dose (1 mg/Kg im) of SUL was administered alone and, 24 h later, together with 0.1 U/Kg iv of insulin (insulin tolerance test: ITT) to six male volunteers (age 20 to 32 yr). A control standard ITT (0.1 U/Kg iv) was also performed 7-10 days later. Plasma samples for the evaluation of PRL were taken in basal conditions and at regular intervals after each drug administration. In the first protocol, PRL showed a significant increase (peak values at 30 min) after SUL administration in both phases (phase A: 54.8 +/- 5.6 ng/ml, mean +/- SE vs 6.4 +/- 0.3, p less than 0.001. Phase B: 77.5 +/- 3.9 vs 7.0 +/- 0.6, p less than 0.001). Twenty-four h later, PRL levels were still higher than basal and were not affected by the administration of SUL + PL or SUL + TRH. Also in the second protocol, SUL alone induced a significant PRL increase (peak values at 30 min: 47.1 +/- 7.2 vs 4.2 +/- 0.5, p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Radio-immunoassay of salivary progesterone for monitoring ovarian function in female infertility.

Fifty-two women, aged from 25 to 41 years, with infertility due to chronic anovulation were admitted to the study together with 36 age-matched controls with proven ovulatory cycles. Paired plasma (3 ml) and whole unstimulated saliva (10 ml) samples were collected over a 30 day period, starting from the first day of a menstrual bleeding, in patients, and throughout the menstrual cycle, in controls. Salivary progesterone levels, measured in women with infertility, ranged from undetectable values to 16 pmol/l during the first, and from 36 to 98 pmol/l during the second half of the monitoring period. In eugonadal women the steroid levels ranged from 34 to 46 pmol/l and from 96 to 780 pmol/l during the follicular and luteal phases, respectively. The saliva/plasma progesterone ratio ranged from 0.58 to 2.71 p. cent and a good correlation between salivary and plasma levels was found at each time of monitoring. Many (86 p. cent) of patients, which were randomly allocated to a low- or high-dose epimestrol administration schedule, appeared to be sensitive to the drug, achieving, after therapy, salivary progesterone levels which were within the range of controls. Since correct assessment of luteal function in basal conditions and during therapy requires multiple steroid measurements, and since saliva can be obtained by non-invasive techniques, salivary assays represent an attractive alternative to plasma ones for monitoring ovarian activity, also during specific treatment.

Adult↗
PubMed1985

Naloxone inhibits sulpiride-induced hyperprolactinaemia in man.

In order to evaluate the interaction between the opiate-like peptidergic pathways and the dopaminergic system in modulating prolactin (PRL) secretion, ten normal volunteers were studied according to a double-blind, cross-over, randomized experimental design. A group of five subjects was given a fixed dose of sulpiride (a selective antidopaminergic agent, 25 mg i.v.) plus either placebo or three different doses of naloxone (a selective opioid antagonist, 0.2, 0.4, 0.8 mg i.v.) while a second group of five subjects received the same drugs in a 'reverse' protocol, i.e. a fixed dose of naloxone (0.4 mg i.v.) plus either placebo or increasing doses of sulpiride (25, 50, 100 mg i.v.). In both groups, the drugs were injected simultaneously and blood samples for PRL determination were taken at various intervals during the 15 min preceding drug injections and then over the following 4 h. Naloxone (0.4 mg i.v.) per se did not induce any modification of plasma PRL levels, but reduced to a significant extent sulpiride-induced hyperprolactinaemia (P less than 0.02). However, a higher dose of naloxone (0.8 mg i.v.) did not cause significant changes in sulpiride-stimulated PRL levels. Increasing dosages of sulpiride (up to 100 mg i.v.) reversed the blunted response of PRL after sulpiride, 25 mg, in presence of naloxone. Our data show that naloxone, at a dose of 0.4 mg i.v. inactive per se on basal PRL levels, is able to blunt significantly sulpiride-induced hyperprolactinaemia. This suggests that, in man, opioid peptides are able to influence PRL release after antidopaminergic stimuli.

Adolescent↗
PubMed1984

Possible mechanism of prolactin unresponsiveness to repeated sulpiride administration in man.

The mechanisms of prolactin (PRL) unresponsiveness to repeated sulpiride (SUL) injections were investigated in 7 normal males. The experimental protocol consisted of two phases, separated by a 5 day interval. In both phases the administration of 1 mg/kg i.m. of SUL was followed 24 hours later, by the administration of the same dose of SUL together with either placebo (PL, 2 ml saline i.v.) or TRH (200 mcg i.v.). A control TRH test (200 mcg i.v.) was also performed. PRL showed a significant increase after the administration of SUL alone in both phases. Twenty-four hours later plasma PRL was still higher than the basal level and it was not significantly modified by administration of SUL + PL, or by SUL + TRH. The data seem to show that the lack of responsiveness of PRL to repeated administration of SUL is not due to refractoriness of dopaminergic receptors but probably to exhaustion of the hypophyseal PRL pool.

Adult↗
PubMed1984

Multicentre study of effects of Org OD 14 on endometrium, vaginal cytology and cervical mucus in post-menopausal and oophorectomized women.

A multicentre study covering 69 post-menopausal or oophorectomized women was performed to determine whether Org OD 14 [7 alpha, 17 alpha)-17-hydroxy-7-methyl-19-norpregn-5(10)-en-20-yn-3-one) administered orally in a daily dose of 2.5 mg for 90 consecutive days induces endometrial proliferation. The treatment with Org OD 14 was continued in combination with 1 mg/day of lynestrenol from day 91 for 10 days to ascertain whether secretory transformation of the endometrium and subsequent withdrawal bleeding would occur. Endometrial biopsies were obtained before treatment and on day 91. The effects of Org OD 14 on vaginal mucosa and cervical mucus were also evaluated. Org OD 14 did not display any effect on the endometrium in 56 of the study subjects (83.5%). Weak stimulation (initial proliferation) was seen in 11 of the subjects (16.4%) and withdrawal bleeding occurred in only 5 of these after cessation of the combined treatment with lynestrenol. However, moderate 'oestrogenic' effects on vaginal mucosa and cervical mucus were induced in all study subjects.

Adult↗
PubMed1983

Effects of sulpiride induced hyperprolactinemia on testosterone secretion and metabolism before and after HCG in normal men.

The purpose of the study was to investigate the effects of sulpiride-induced hyperprolactinemia on testicular functions, as assessed by evaluation of plasma testosterone (T), dihydrotestosterone (DHT) and 17 beta-estradiol (E2) levels. An HCG test (5000 IU on three consecutive days) was performed in basal conditions and after 12 and 26 days of sulpiride treatment (150 mg daily) in 7 male volunteers, 19 to 32 years of age, as well as in 6 sulpiride-free controls. The results show that after 12 days of induced hyperprolactinemia (mean increase 400%) the T response to HCG was similar to basal test; after 26 days however, the increase of T mean plasma levels was significantly greater. The increase in E2 significantly correlated to that of T during the first and second HCG tests, but no longer after 26 days of hyperprolactinemia, resulting in an imbalance of the E2/T ratio of plasma increments. The response of DHT to HCG was significant in basal conditions and after 26 days of sulpiride and always correlated with T behavior. Data obtained in our experimental conditions suggest that PRL might enhance T secretion. 5 alpha-reductase activity seemed to be partially affected after 12 days of treatment, while a significant inhibition seemed to be exerted on aromatase activity.

Adult↗
PubMed1982

Applicability of salivary testosterone measurements for the follow-up of therapy of idiopathic hirsutism.

Preliminary data on the applicability of salivary evaluations of testosterone (T), in comparison to plasma evaluations, in monitoring the effects of prednisone treatment in hirsutism are shown by the authors. 7.5 mg daily were administered p.o. to 4 volunteers affected by idiopathic hirsutism and to a fifth case in whom later surgery demonstrated the presence of adrenal virilizing tumour. While in the latter no modification either in plasma or salivary levels of the hormone was shown, in the four cases of idiopathic hirsutism a striking decrease of T levels was observed both in plasma (P less than 0.02) and in saliva (P less than 0.01). The two variations were moreover highly correlated (r = 0.80; P less than 0.001). Data obtained, although from a limited number of cases, seem then to confirm the validity of salivary T determination in this clinical condition, in whom the need of repeated evaluations, if performed on plasma, may become particularly stressful for the patient.

Adolescent↗
PubMed1981

Endocrinological and clinical investigations in post-menopausal women following administration of vaginal cream containing oestriol.

The maturation value (MV), cervical mucus parameters (ferning, Spinnbarkeit), oestrone (E1), oestradiol (E2), oestriol (E3), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), thyrotropin (TSH), growth hormone (GH), sex hormone binding globulin (SHBG), corticosteroid binding globulin (CBG) and thyroxin-binding globulin (TBG) were determined in 11 post-menopausal women presenting with vaginal atrophy prior to, and following, treatment with Ovestin vaginal cream containing 0.5 mg/day of E3 for 8 wk. In 6 of the patients E3 was measured during frequent plasma sampling on days 1, 21 and 56; in the same patients and on the same days TRH-stimulated PRL, TSH and GH levels were estimated. While the therapy induced a sharp rise in the MV, there was a moderate effect on ferning/Spinnbarkeit. Baseline E3 rose from undetectable levels to a mean value of 86.8 pmol/l at day 21. E3 levels achieved during frequent plasma sampling were higher on day 1 than on days 21 and 56 - a decline of the areas under the response curves being significant (P2-sided = 0.03). There was a slight suppression of FSH and LH. No changes in the circulating levels of E1, E2, SHBG, CBG, TBG, PRL, TSH and GH were seen. TRH-stimulated PRL, TSH and GH levels remained unaffected. Clinical effect was excellent and no untoward effects were reported.

Administration, Topical↗
PubMed1981

Influence of conjugated oestrogens on circulating oestradiol, oestrone, LH, FSH and prolactin levels in postmenopausal women.

The effects on plasma 17-beta-oestradiol (E2), oestrone (E1), LH, FSH and prolactin (PRL) levels of 1.5 mg conjugated oestrogen, administered daily per os for 20 consecutive days, was investigated in six postmenopausal women aged 60-68. Both E2 and E1 increased progressively and significantly (p less than 0.001) from 18 and 28 pg/ml to 32 and 108 pg/ml, respectively, at the end of treatment; five days after the last dose both E2 and E1 had fallen to pretreatment levels (p greater than 0.05). LH and FSH decreased progressively and significantly (p less than 0.001) from 114 and 105 mlU/ml (before therapy) to 43 and 36 mIU/ml, respectively, after oestrogen administration. One week after interruption of treatment, both LH and FSH were significantly higher (p less than 0.001) than that obtained at the end of therapy. No significant variation (0.05 greater than p greater than 0.02) was observed for plasma PRL during and after oestrogen administration. Such results indicate that in postmenopausal women the specific enzymatic mechanism of oestrogen interconversion are maintained and that there is no increase of prolactin. IN this was, the possible effects on the development of breast cancer by elevated levels of this hormone, usually observed during long-term oestrogen therapy, would be avoided.

Aged↗
PubMed1980

A group-comparative study of effects of Ovestin cream versus Premarin cream in post-menopausal women with vaginal atrophy.

Fourteen post-menopausal women with vaginal atrophy applied, intravaginally, Ovestin cream (0.5 mg oestradiol/day; 7 patients) or Premarin cream (1.25 mg conjugated oestrogens/day; 7 patients) for 3 wk. Effects on plasma E1, E2, E3, FSH, LH, PRL, TRH-stimulated PRL release, SHBG, and on maturation value (MV), ferning (F) and spinnbarkeit (S) were studied. Endometrial biopsies at pre-treatment and at 2 wk were obtained from 2 patients from each group. Premarin induced a significant and progressive rise in E1 and E2 levels and in SHBG, whereas Ovestin induced no changes. Both creams increased E3 slightly and suppressed FSH and LH, Premarin suppression of FSH and LH being significantly greater. No significant changes in PRL or TRH-stimulated PRL release occurred with either cream. A similar, marked rise in the MV occurred, but the effect of Premarin on F and S was significantly greater. Endometrium remained atrophic in the 2 Ovestin-treated patients, but moderate proliferation occurred in the 2 Premarin-treated patients. The data showed Ovestin cream to be superior to Premarin cream because of the absence of undesirable effects on E1 and E2 levels and the subsequent changes in SHBG and endometrium.

Aged↗