Plasma Of Normal Men Research Articles

Levels of hepatocyte growth factor/scatter factor (HGF/SF) in seminal plasma of patients with andrological diseases.

Hepatocyte growth factor/scatter factor (HGF/SF) has all the characteristics of a molecule suitable for functioning in regulatory networks of motility, such as the spermatogenic epithelium, where spermatogenic cells must migrate between the cells of Sertoli, and it exerts its effect through binding of its high-affinity receptor (c-met). Considering the findings that c-met receptor is expressed in the human testis and on spermatozoa, and that HGF/SF in seminal plasma consists of pro-HGF/SF, mature alphabeta-HGF/SF, and less active forms of HGF/SF, we investigated the concentration and biological activity of HGF/SF in seminal plasma and their correlation with parameters of spermatogenesis to obtain better insight into mechanisms that may be involved in the pathogenesis of male infertility. We also evaluated the potential value of assessment of hepatocyte growth factor concentration and its bioactivity for the diagnosis of certain pathological conditions of male reproduction. We studied the concentration and biological activity of HGF/SF in seminal plasma of normal men and of patients with a range of andrological diseases or conditions by measuring HGF/SF in seminal plasma by enzyme-linked immunosorbent assay and by scatter assay using Madin-Darby canine kidney epithelial cells. We identified three sources of HGF/SF in seminal plasma. In samples from vasectomized men (n = 30; 2.01 ng/ml) and in split ejaculate samples (n = 6; 1e fraction 2.75 ng/ml, 2e fraction 1.62 ng/ml), a prostatic origin can be certified. This HGF/SF has low biological activity (133.3 U/ml). In inflammation of the accessory sex glands (n = 40), a high amount of HGF/SF (3.04 ng/ml) can be generated by white blood cells and has moderate scatter activity (426.7 U/ml). In normozoospermic samples, there is a lower amount of HGF/SF (1.12 ng/ml), with strong scatter activity (1280.0 U/ml). Finally, the clear difference between the low amount of HGF/SF (1.06 ng/ml) with poor scatter activity (106.6 U/ml) in oligozoospermic samples (n = 28) and the high amount of HGF/SF (3.35 ng/ml) with strong scatter activity (853.3 U/ml) in samples from men with azoospermia of primary testicular failure (n = 18) suggests a mainly testicular origin, with different activity in different pathological conditions.

Parallel nocturnal secretion of melatonin and testosterone in the plasma of normal men.

Differences and similarities in the temporal organization of hormone secretion in plasma reflect the activity of CNS pacemakers. One aspect of this activity, the temporal synchronization of the secretion of different hormones is still poorly understood. We report the analysis of melatonin and testosterone plasma concentrations during two nights in 6 normal healthy young men. Blood was collected every 20 min between 2040 and 0640. Plasma testosterone concentrations increased by 1.5- to 2-fold during the second part of the night, and melatonin by 2.5- to 4-fold. In each subject, the individual temporal pattern of melatonin was quite stable over the two nights of sampling, while testosterone profiles showed fluctuations. There was a high degree of parallelism in these two hormones nocturnal secretion. These results, together with previous studies, suggest that melatonin might entrain the nocturnal secretion of testosterone.

Plasma protein s activity measured using protac, a snake venom derived activator of protein C

Functional activity of protein S, a cofactor of activated protein C-dependent inhibition of blood coagulation, in human plasma was measured by using Protac, a snake venom derived activator of protein C. This assay appeared to be specific for protein S, because 1) the activated partial thromboplastin time of protein S-depleted plasma depended on the purified protein S added in the presence of Protac; and 2) the level of protein C in plasma sample (0 to 10 μg/ml) had no influence on the clotting time. The cofactor activity of protein S in the plasma of normal men (n=16) and women (n=14) was 99.4 ± 23.8% and 98.6 ± 24.5% respectively. The protein S activity in the plasma of pregnant women at pre- and post-partum (n=14), and that in the plasma of patients under warfarin therapy (n=20) were 46.2 ± 18.9%, 45.8 ± 19.6% and 24.0 ± 15.7%, respectively. In these plasmas, the levels of protein S activity were lower than those of total protein S antigen, but were similar to those of free protein S antigen. In 16 patients out of two families with congenital protein S deficiency, the protein S activity, the free antigen and the total antigen were 9.4 ± 6.9%, 13.3 ± 4.6% and 57.4 ± 20.7%, respectively. There was no significant relationship between the level of protein S activity and that of a complemental C4b-binding protein antigen in any of these patients.

Na-K-ATPase-inhibiting and glucose-6-phosphate dehydrogenase-stimulating activity of plasma and hypothalamus of the Okamoto spontaneously hypertensive rat.

The plasma of normal man and the rat, and an acetone extract of hypothalamus from the rat, have an ability to inhibit Na-K-ATPase which is related directly to salt intake. The ability of the plasma to inhibit Na-K-ATPase is raised in essential hypertension. The ability of plasma and of an acetone extract of hypothalamus from six spontaneously hypertensive (SHR) rats and six normotensive control (WKY) rats to inhibit Na-K-ATPase of fresh guinea-pig kidney was studied using cytochemical bioassay techniques. With a validated assay, which measures the capacity of biological samples to stimulate glucose-6-phosphate dehydrogenase (G6PD) as an index of their capacity to inhibit Na-K-ATPase, the mean G6PD-stimulating ability of the plasma from the SHR and the WKY rat was 772.3 +/- 48.1 units/ml and 12.5 +/- 2.6 units/ml respectively (P less than 0.01) and of the hypothalamic extracts it was 2.2 +/- 1.7 X 10(8) and 4.5 +/- 1.8 X 10(4) units/hypothalamus (P less than 0.01). With a semi-quantitative cytochemical assay, which measures Na-K-ATPase activity directly, plasma and an acetone extract of hypothalamus from the spontaneously hypertensive rat had much greater capacities to inhibit Na-K-ATPase than plasma and extract from the WKY rat. These raised levels of Na-K-ATPase inhibitory activity in the plasma of the SHR rat are similar to the highest values found in the plasma of patients with essential hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Inhibition of LCAT in plasma from man and experimental animals by chlorpromazine.

Chlorpromazine (CPZ), a major tranquilizer, was found to be a potent inhibitor of lecithin:cholesterol acyltransferase (LCAT, EC 2.3.1.43) in the plasma of normal man, rat, rabbit and dog in vitro. The inhibitory effect of CPZ reached 35-50% at 0.5 mM depending on species; dog plasma LCAT appeared to be somewhat more sensitive than that of the other species. In rats fed CPZ or lidocaine for 14 days (0.05% in the diet), there was no statistically significant change in total plasma cholesterol levels or the size of the plasma-free (unesterified) cholesterol pool. However, 5 hr after an intracardial injection of [14C]cholesterol, the percentage of plasma [14C]cholesterol that was esterified was significantly lower (ca. 6%, p less than 0.05) in the CPZ-treated group, suggesting that CPZ may also inhibit LCAT To some extent in vivo. The percentage of plasma [14C]cholesterol esterified in the lidocaine-treated group was similar to control values and did not reflect its ability to inhibit LCAT in vitro.

Further characterization and immunological studies of human sex steroid binding plasma protein

The Sex steroid binding plasma protein (Sbp) from human late pregnancy plasma was purified by a three-steps procedure including ammonium sulfate precipitation, affinity chromatography and preparative electrophoresis. The biospecific adsorbent was prepared by coupling 1α-carboxymethyl-5α-dihydrotestosterone to AH-Sepharose 4B. Homogeneity of Sbp was shown in polyacrylamide gel electrophoresis in the presence or absence of sodium dodecyl sulfate and in immunoelectrophoresis. The mean molecular radius of 2.99 nm and an apparent molecular weight of 92,000 daltons were obtained for the native pure Sbp using polyacrylamide gel electrophoresis, whereas in the presence of sodium dodecyl sulfate, a value of 67,000 daltons for the molecular weight of denatured Sbp was determined. A highly specific and precise radioimmunoassay for human Sbp has been developed using a monospecific rabbit anti-human Sbp antiserum. No cross-reactivity was observed with transferrin, IgG or α-fetoprotein and with any mammalian plasma except primate plasma. The concentration of Sbp (mean ± SEM) in the plasma of normal men, normal, pregnant and hirsute (non pregnant) women, were measured as 4.02 ± 0.57, 8.21 ± 0.56, 77.5 ± 4.9, and 6.17 ± 0.36 μg/ml, respectively. The sensitivity was 0.3 ng of pure Sbp at the highest antiserum dilution of 1 122,000 .

Sex-hormone-binding globulin in the plasma of normal men and patients with benign prostatic hypertrophy.

Sex-hormone-binding globulin (SHBG) was measured in the plasma of normal men aged 30--50 yr, normal men 50--70 yr of age, and men 50--70 yr of age suffering from benign prostatic hypertrophy (BPH). The level of binding proteins in normal "young" men decreased approximately 45% in normal "older" men. A 100% rise was observed in BPH patients as compared to normal older men. This increase seemed to be related to a rise in SHBG and also to the appearance of binding species of smaller molecular weight than that of SHBG.

The Detection of Cysteine-Homocysteine Mixed Disulphide in Fasting Plasma of Normal Man and the Difference in Levels Found between Men and Women

The Detection of Cysteine-Homocysteine Mixed Disulphide in Fasting Plasma of Normal Man and the Difference in Levels Found between Men and Women

Human calcitonin: Immunologic assay, cytologic localization and studies on medullary thyroid carcinoma

Current assay methods do not define the absolute concentrations of calcitonin in plasma of normal man. In our experience, the concentration was <100 pg/ml in more than 75 per cent of 2,000 normal subjects and <250 pg/ml in the remainder. Low circulating calcitonin levels in man are in part due to the small number of calcitonin-producing cells (C cells) in the normal thyroid gland. The distribution of these cells has been mapped by using an immunoperoxidase bridge technic that identifies calcitonin-containing cells. Normal C cells are both parafollicular and intrafollicular in location and are concentrated, singly or as groups of 2 or 3 cells, in the middle third of the lateral lobes lying deep within the gland along a hypothetical central axis of each lobe. Distribution of calcitonin content within the gland correlates well with C cell distribution. Medullary carcinoma of the thyroid gland (MTC) is a calcitonin-producing tumor of C cells that responds to a simple calcium infusion test by increasing the rate of calcitonin secretion These findings form the basis for using measurements of calcitonin in serum as a means to identify, at an early stage of the disease, persons at risk for the familial form of the tumor. In studies of five kindreds, preoperative prediction of MTC was correct in 38 persons on the basis of serum calcitonin responses to calcium infusion; in fewer than 20 per cent of these cases was there any other clinical or laboratory evidence of disease. In four additional persons, annual testing revealed minimal progressive increases in serum calcitonin concentrations, and thyroid glands removed surgically showed focal hyperplasia of C cells in the middle and upper thirds of both lateral lobes. The prognosis after treatment early in the disease requires long-term follow-up; however, 40 to 50 per cent of such persons studied have had unmeasurable serum calcitonin values postoperatively (even after calcium infusion) for periods of up to 2 to 3 years. Preliminary findings suggest that the amyloid of MTC may be composed, in part, of calcitonin.

Stimulation and suppression of aldosterone in plasma of normal man and in primary aldosteronism.

The effect of stimulating and suppressive influences on plasma aldosterone in normal man and in patients with primary aldosteronism were studied using a sensitive double-isotope derivative assay for aldosterone. In normal sitting subjects, values were 9.2+/-0.9 (SE) mmug/100 ml and in subjects supine for 1 hr plasma aldosterone was 5.2+/-0.4 (SE) mmug/100 ml. Adrenocorticotropic hormone (ACTH), 0.5 U/hr, produced a rise of 46.8+/-22 (SE) mmug which was similar to the 1-hr effect of an infusion of a synthetic ACTH (beta(1-24), Cortrosyn). Angiotensin II in pressor amounts also increased plasma aldosterone 21.5+/-2.9 (SE) without change in plasma cortisol, whereas a subpressor dose ([unk]) had minimal effect.Fludrocortisone, 1.2 mg/day for 3 days, suppressed plasma aldosterone levels to 1.8+/-0.7 (SE) mmug/100 ml in five normal sitting subjects (P < 0.01); however, dexamethasone, 2 mg/day for 1-2 days, did not lower aldosterone concentration in plasma. In six patients with primary aldosteronism, plasma aldosterone on a normal sodium diet was 39.1+/-4.4 (SE) which differed significantly from normal sitting or supine subjects (P < 0.001). In contrast to the normal subjects, neither a pressor infusion of angiotensin II for 1 hr, nor fludrocortisone, 1.2 mg/day for 3 days, impressively altered plasma aldosterone levels. This approach appears to be useful for the study of the acute physiology and control mechanisms of aldosterone production in normal and hypertensive man.

Distribution, conjugation, and excretion of labeled aldosterone in congestive heart failure and in controls with normal circulation: development and testing of a model with an analog computer.

The distribution and clearance of aldosterone from plasma determine the fraction of secreted hormone reaching sites where the cellular actions of the hormone occur. Tait, Tait, Little, and Laumas (1) described the disappearance of aldosterone from plasma of normal man in terms of a two compartment system. Davis, Olichney, Brown, and Binnion (2) showed that the volumes of distribution and rates of clearance of aldosterone are reduced in dogs with experimental heart failure and low cardiac output. Our findings indicate that marked alterations in distribution and clearance of aldosterone are present in patients with congestive failure. Tait, Little, Tait, and Flood (3) estimated the mean plasma concentration of aldosterone in human plasma from the secretion rate and the plasma clearance rate. Ayers and his colleagues (4) and Tait and associates (5) showed that hepatic clearance of aldosterone is subnormal in dogs or in man in congestive failure (4). Camargo, Dowdy, Hancock, and Luetscher (6) demonstrated that reduced hepatic clearance and extraction of aldosterone may contribute to an increased concentration in plasma of patients with heart failure. The liver extracts aldosterone from plasma and returns conjugates and metabolites to plasma, in

The levels of individual free amino acids in the plasma of normal man at various intervals after a high-protein meal.

The levels of individual free amino acids in the plasma of normal man at various intervals after a high-protein meal.

Penicillin G and benzethacil by mouth: comparison of penicillin levels in plasma of normal men after single oral doses.

Penicillin G and benzethacil by mouth: comparison of penicillin levels in plasma of normal men after single oral doses.