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Biomedical subjects

F Fraioli

Publications and source records attributed to F Fraioli.

At least 55 records · Page 3Linked to original sources
PubMed1983

Naloxone inhibits exercise-induced release of PRL and GH in athletes.

Opiate peptides stimulate the release of GH and PRL, and such changes have also been reported following physical exercise. To investigate opiate involvement in the exercise-induced release of these hormones, eight professional athletes were exercised to 80% of their maximal heart rate on a bicycle ergometer. This exercise alone induced an increase in circulating mean GH (basal to maximal level, 3.1 +/- 0.9 ng/ml-27.3 +/- 5.9 ng/ml) and mean PRL level (6.1 +/- 1.1 ng/ml-19.5 +/- 1.9 ng/ml). Infusion of naloxone (0.3 mg/min) antagonized these responses in mean serum GH (5.6 +/- 1.0 ng/ml to 8.6 +/- 1.1 ng/ml) and PRL levels (6.4 +/- 1.1 ng/ml-8.1 +/- 1.2 ng/ml), which were both significantly less than during the control infusions (P less than 0.01). It is suggested that certain forms of stress stimulate the release of PRL and GH via endogenous opiate peptides.

Adult↗
PubMed1983

Plasma beta-endorphin, beta-lipotropin, and met-enkephalin concentrations during pregnancy in normal and drug-addicted women and their newborn.

Most studies of plasma beta-endorphin concentrations in pregnant women show that these are highly elevated. This might indicate a role for opiate peptides during pregnancy and in the fetus-mother relationship. We measured plasma beta-endorphin, beta-lipotropin, and met-enkephalin concentrations in normal and drug-addicted women during pregnancy, labor, and delivery, and in their newborn infants. Peptides were measured by RIA after extraction and concentration on silica columns and separation by high pressure liquid chromatography. In both normal and drug-addicted mothers we found an increase in plasma beta-endorphin during pregnancy, without a concomitant increase in plasma beta-lipotropin or metenkephalin. Only beta-lipotropin increased dramatically in both groups at delivery, whereas beta-endorphin and met-enkephalin remained unchanged. Peptide concentrations in umbilical plasma were similar to those in peripheral plasma of the mothers. On day 1 of life plasma beta-endorphin, beta-lipotropin, and met-enkephalin concentrations in the newborn from normal mothers were higher than in nonpregnant adult subjects and gradually decreased toward normal adult values by day 5 of life. Plasma beta-endorphin, beta-lipotropin, and met-enkephalin concentrations of newborn infants of drug-addicted mothers increased dramatically on day 2 and 3 of life, up to 1000-fold the concentrations of normal adults, and remained elevated up to 40 days after birth. In conclusion, beta-endorphin, beta-lipotropin, and met-enkephalin concentrations during pregnancy are not affected by drug addiction, whereas in the newborn of drug addicted mothers concentrations of these compounds are markedly increased.

Adult↗
PubMed1983

Mode of secretion of bioactive luteinizing hormone in man.

The episodic nature of gonadotropin secretion was originally defined by RIA of circulating LH concentrations. We analyzed the pulsatile release of biologically active LH by measuring plasma LH concentrations in the rat interstitial cell testosterone bioassay. A computer algorithm to discriminate true biological signals (LH pulses) from background variation was applied to serially sampled LH data from seven men and seven postmenopausal women. Our results indicate the following. 1) In all subjects, mean bioactive LH values were considerably higher than immunoactive levels, (41.4 +/- 15.1 and 450 +/- 243 mIU/ml vs. 10.2 +/- 2.3 and 83 +/- 35 for men and postmenopausal women, respectively). There was a corresponding 4-fold increase in the total area under the bioactive LH secretion profile compared with that defined for the immunoactive hormone. 2) The absolute amplitude of the bioactive LH peaks was 0.5- to 11-fold higher than the immunoactive values. 3) Although the majority of the LH peaks were coincident by bioassay and RIA, significant dissociation occurred in 20% and 28% of the total LH peaks (rat interstitial cell testosterone bioassay and RIA) in men and postmenopausal women, respectively. 4) Significant increases in the bioactive to immunoactive ratio over interpulse bioactive to immunoactive levels occurred in 98% of the pulses in the men and 83% of those in postmenopausal women. Also, in two men, peaks of LH bioactivity exceeding 100 mIU were followed by major increases in serum testosterone concentrations. These findings demonstrate the value of bioactive LH determinations and indicate that LH is secreted in pulses of high biological activity. The in vitro LH bioassay provides a sensitive and appropriate estimate of functionally active LH in the circulation.

Adult↗
PubMed1982

Treatment of benign fibrocystic disease of the breast with 2-bromo-alpha-ergocryptine (CB 154).

A total of 192 patients with benign fibrocystic disease of the breast were studied. Diagnosis was based on the clinical picture, xerography, and/or mammography. Most of the patients were 30-45 years old. Hormonal studies including serum PRL, 17-beta-estradiol, progesterone, and gonadotropins were performed by means of specific and sensitive RIA techniques. Patients were allotted to treatment with 3 x 25 mg p.o. 2-bromo-alpha-ergocryptine (CB 154, Parlodel, Sandoz) continuously for a period of 3 months. In an attempt to establish a possible relationship between PRL levels and the disease, patients were divided into two groups with high or normal levels of PRL. Results indicate an improvement or complete recovery in about 75% of the cases. These results are independent of PRL levels. According to our experience CB 154 seems to be the most effective treatment of this disease.

Adult↗
PubMed1981

The analgesic effect of calcitonin in humans: studies on the role of opioid peptides.

The possibility that the analgesic action of calcitonin could be due to variations in beta-endorphin levels in both peripheral blood and cerebrospinal fluid was studied. A total of 40 microgram of synthetic salmon calcitonin was injected i. v. in four male volunteers undergoing minor operations under rachianesthesia. Beta-Endorphin was determined in blood and cerebrospinal fluid samples that were collected before and at regular intervals after calcitonin injection. No statistically significant variation in beta-endorphin levels was observed either in peripheral blood or cerebrospinal fluid. Since the injected calcitonin was free of contaminants (demonstrated by both high pressure liquid chromatography and radioimmunoassay of endorphin made on the injected preparation) and since an increase was observed in the immunoreactive calcitonin in cerebrospinal fluid following calcitonin i. v., self-analgesic action may be hypothesized, even though action through prostaglandins or other systems cannot be excluded.

Adult↗
PubMed1980

Physical exercise stimulates marked concomitant release of beta-endorphin and adrenocorticotropic hormone (ACTH) in peripheral blood in man.

ACTH and beta-endorphin have been evaluated by means of a specific and sensitive radioimmunoassay in athletes reaching a status of physical stress. A concomitant marked increase of these 2 peptides has been recorded. The implications of this finding lead to the conclusion that stress stimulates the synthesis of the common precursor (31 K) in the pituitary.

Adrenocorticotropic Hormone↗
PubMed1980

Human placental beta-endorphin.

Human acid-acetone placental powder (PP) has corticotrophin-like and beta-endorphin(beta-EP)-like activity. In a beta-EP radioimmunoassay the PP showed a potency of 4.82 ng/mg protein. In Sephadex G-75 filtration and high pressure liquid chromatography, the beta-EP-like activity of PP was found in the corresponding chromatographic fractions as standard beta-EP. The PP tested for opiate activity in a radioreceptor assay showed a dilution curve parallel to that of synthetic beta-EP.

Chromatography, Gel↗
PubMed1980

Effects of a new glucocorticoid, deflazacort, on pituitary-adrenal function in man: a comparison with prednisone.

The influence on plasma ACTH and cortisol and on blood sugar have been evaluated in seven volunteers after single oral doses of prednisone 4 mg and 8 mg and deflazacort 5 mg and 10 mg. Drugs were administered at midnight to achieve a maximum inhibitory effect on the hypothalamic-pituitary-adrenal axis. No difference was detected in the majority of cases between the high and the low dose of each drug. In particular, the results obtained with the higher doses show a significant effect of both drugs on ACTH (at hour 4 after drug administration) and on cortisol (at hours 4, 8, 12 and 16). As for blood sugar, the hyperglycemic activity of deflazacort appears to be lower than prednisone at hours 12 and 16. On the whole, the potency of deflazacort appears similar to that of prednisone.

Adrenocorticotropic Hormone↗
PubMed1980

[Droperidol. Action on hemodynamic and oxygen consumption changes (author's transl)].

Hemodynamic and oxygen consumption changes following general anesthesia were studied in 11 patients who did and in 11 patients who did not received droperidol at the end of operation. Both group were similar with respect to age, duration of anesthesia, doses of anesthetic drugs, and hemodynamic and oxygen consumption values immediately at the end of operation. The highest oxygen consumption measurements which were selected as representative of the maximal metabolism of the recovery period showed that the following parameters were lower in the droperidol group than in the non-droperidol group: oxygen consumption (162 +/- 12 and 238 +/- 19 ml/min/m2 respectively), cardiac index (3.0 +/- 0.2 and 4.4 +/- 0.4 l/min/m2), mean arterial pressure (11 +/- 6 and 129 +/- 5 torr), stroke index (27 +/- 3 and 46 +/- 4 ml/m2) left ventricular stroke work index (38 +/- 5 and 77 +/- 8 gm/m2) and PaCO2 (39 +/- 2 and 49 +/- 2 torr). The measurements performed after extubation were similar in both groups. These data show a metabolic and hemodynamic stabilizing effect of droperidol during recovery which may be useful in high-risk patients.

Anesthesia↗