Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To study the hormonal and metabolic effects of prostacyclin (PGI2), 6 healthy women were infused iv with PGI2 (1, 2, 4, and 8 ng/kg/min. each for 20 min) dissolved in glycine buffer, or with glycine buffer only. Serial blood samples collected before, during and after the infusion were assayed for FSH, LH, prolactin, growth hormone, thyrotrophin, oestradiol, progesterone, testosterone, cortisol, thyroxine, triiodothyronine, renin, aldosterone, glucose, insulin, glucagon, cholesterol, high density lipoprotein-cholesterol, triglycerides, alkaline phosphatase, alanine and aspartate aminotransferases, bilirubin, sodium, potassium, chloride, calcium, inorganic phosphorous, creatinine and uric acid. PGI2 infusions were accompanied by increased levels of prolactin, growth hormone and cortisol, probably due to the stressful side-effects during PGI2 infusion. In addition, plasma renin activity, glucagon and blood glucose increased, whereas the other variables measured did not change. These PGI2-effects should be kept in mind, when PGI2 is used in clinical practice.
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PMID:Hormonal and metabolic effects of intravenous infusion of prostacyclin in healthy women. 675 11

The modulation of transferrin secretion by FSH and epidermal growth factor (EGF) was studied in highly pure, primary cultures of immature rat Sertoli cells grown on a reconstituted basement membrane (Matrigel) in bicameral chambers. Sertoli cell purity was assessed by (1) morphometry, (2) alkaline phosphatase cytochemistry (a specific marker enzyme for peritubular cells) and (3) immunocytochemistry for the alpha-isoform of smooth muscle actin in contaminating peritubular cells. Results revealed a less than 0.5% peritubular cell contamination. During initial periods of culture with EGF or FSH alone or in combination, both EGF and FSH alone maintained transferrin secretion over basal values and their effects were additive. At subsequent times, EGF alone maintained transferrin secretion, but to less extent than did FSH alone, and inhibited significantly the ability of FSH to maintain transferrin secretion. The ratio of polarized transferrin secretion in response to FSH, EGF, or in combination was also examined. FSH significantly reversed the polarity of transferrin secretion, whereas EGF, although significantly reducing the ratio of apical to basal transferrin secretion, did not lead to a preferential basal secretion of transferrin. The change in the apical:basal transferrin secretion ratio, however, was not due to a reversal of the apically secreted transferrin towards a basal direction, but rather to an increase in the total basally secreted transferrin. The effects of cell density effects on transferrin secretion were then examined. At low cell density, the relative ability of EGF and FSH together to maintain transferrin secretion was greater than at high cell density, but overall transferrin secretion was greater as cell density increased. The inhibition of FSH by EGF on transferrin secretion was also density dependent: EGF significantly inhibited FSH effects at low cell density, but failed to do so at high cell density. These results suggest that regulation of transferrin secretion by Sertoli cells appears to be under dual control, involving both FSH and EGF and may provide an explanation for the mechanism by which EGF exerts a regulatory role in spermatogenesis.
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PMID:Modulation of transferrin secretion by epidermal growth factor in immature rat Sertoli cells in vitro. 802 75

We measured lunbar spine and femoral neck bone mineral density (BMD); urine markers of bone resorption; serum markers of bone formation; and serum gonadotrophin, estradiol and inhibin concentrations in a population-based cohort of 281 women aged 45-57 yr. Women were classified into pre-, peri-, and postmenopausal groups, depending on menstrual bleeding patterns. Compared with premenopausal women, BMD was lower only in postmenopausal women but not in women currently using hormone replacement therapy (HRT). BMD decreased with age in the perimenopausal group. Compared with premenopausal women, perimenopausal women had 20% greater urine N-telopeptide excretion (P < 0.05) and a doubling of gonadotrophin levels (P < 0.01), whereas serum estradiol and bone formation marker concentrations were no different. Postmenopausal Women had greater levels of bone turnover markers (P < 0.0001), except free deoxypyridinoline and type I procollagen propeptide. Among postmenopausal women, bone resorption markers were lower in those using HRT. Levels of nearly all bone turnover markers were positively related to serum FSH concentrations (P < 0.0001). Overall, the major independent predictors of BMD were age, urine N-telopeptide, serum bone alkaline phosphatase, and serum, FSH, whereas urine free deoxypyridinoline was positively related to BMD in pre- and perimenopausal women. In conclusion, the perimenopause is associated with elevated bone resorption rates and declining BMD, and factors in addition to estrogen deficiency may also contribute to the pathogenesis of postmenopausal osteoporosis.
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PMID:Bone turnover markers and bone density across the menopausal transition. 878 98

A new methodological approach using immunohistochemical markers for Sertoli cells (alpha inhibin), peritubular cells (alpha smooth muscle actin), and S-phase cells (bromodeoxyuridine; BrdU) is presented that allows an accurate and simultaneous analysis of morphogenetic and mitogenic changes occurring in vitro. Sertoli cells and peritubular cells were isolated by sequential enzymatic digestion from 7-day-old rats. Laminin, as a major component of the extracellular matrix of the seminiferous tubule, and FSH, as a hormone stimulating Sertoli cell proliferation, were tested for their ability to influence the morphology or mitotic activity of the cultured cells. After fixation, the coverslips were stained for these antigens with use of specific primary antibodies and horseradish peroxidase- or alkaline phosphatase-labeled secondary antibodies for visualization of the respective antigens with different-colored precipitates. This approach allowed us to distinguish the two cell populations, which could not be done unequivocally without the antibody staining. We scored striking changes in cell densities and cell ratios during the culture period. Peritubular cells showed a consistently higher BrdU-labeling index than Sertoli cells. While Sertoli cells were not labeled until Day 7, peritubular cells proliferated as soon as on Day 3, and their density doubled from Day 3 to Day 7. A linear negative correlation was established for Sertoli cell proliferation in response to their local density on the coverslip, indicating contact inhibition as a signal for cessation of mitosis. At high cell densities, this inhibition was partially overcome in the presence of FSH. The presence of laminin had striking effects on the morphogenetic response but only a minor influence on mitogenesis.
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PMID:Discriminative analysis of rat Sertoli and peritubular cells and their proliferation in vitro: evidence for follicle-stimulating hormone-mediated contact inhibition of Sertoli cell mitosis. 882 24

The adult human Sertoli cells produced lactate, estradiol-17beta, transferrin and inhibin; germ cells modulate synthesis of these compounds. In order to study the functional features of human Sertoli cells in vitro, the aim of this study was to measure the lactic dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP) and creatine kinase activities (CK) in primary cultures of Sertoli cells prepared from young men (mean age: 29 years, n = 11). Five LDH isozymes have been found in Sertoli cells, the main fractions being the LDH3 and LDH4; each of them represented 30% of the total LDH activity. Furthermore, CK and ALP activities were measured in Sertoli cells. It is of note that the Sertoli cell ALP activity was 50% lower than that of germ cells. Whatever the Sertoli cell parameter measured herein, there is a great variability between patients and FSH (dbc AMP, as well as retinol, insulin, testosterone) is poorly effective in improving these enzymatic activities in vitro. We have confirmed that GGT was exclusively present in Sertoli cells and thus may be considered as a specific marker. LDH is involved in Sertoli cell glucose transformation and thus provided energetic substrates for germ cells. In contrast, the roles of CK and ALP remains to be clarified. In conclusion, we have demonstrated the existence of several enzymes namely LDH, GGT, ALP and CK in Sertoli cells prepared from adult human testis.
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PMID:Enzymatic properties of adult human Sertoli cells in vitro. 884 50

Two enriched populations of Leydig cells (hLCI and hLCII) have been characterized in human testes; it is noteworthy, that in the presence of hCG the steroid ouput is higher in hLCII when compared to hLCI; conversely, the basal production of steroids is greater in hLCI than in hLCII. The addition of increasing amounts of seminiferous tubule-conditioned medium to the purified Leydig cells leads to a dose-related enhancement of the steroid production in both Leydig cell fractions under basal and hCG-stimulated conditions. It is therefore obvious that a paracrine factor (or factors) from seminiferous tubular origin influences positively and with a high efficiency the human Leydig cell function. The human Sertoli cell synthesizes lactate, estradiol-17beta and several proteins, namely transferrin, ferritin and inhibin. In the presence of germ cells the Sertoli cell production of estradiol-17beta is decreased whereas the transferrin and inhibin outputs are enhanced. In addition the lactate dehydrogenase, gamma-glutamyl transpepetidase, alkaline phosphatase and creatine phosphokinase activities have been quantitated in various human Sertoli cell preparations. It should be kept in mind that germ cells exert an important influence on the adult Sertoli cell secretory activity through either direct contact and/or via secreted factors; moreover germ cells potentialize the stimulating effect of FSH on the Sertoli cell function and indirectly the Leydig cell output of testosterone via the Sertoli cell secretion of paracrine factor(s).
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PMID:Paracrine control of human Leydig cell and Sertoli cell functions. 896 55

Osteoporosis is a major health problem. Little is known about the risk factors in premenopause. Sixty 40-50-year old patients with regular menses were studied cross-sectionally. None of the patients were on drugs known to interfere with bone mass. Patients answered a dietary inquiry and had their bone mineral density (BMD) measured. The Z scores were used for the comparisons. A blood sample was taken for the determination of FSH, SHBG, estradiol, testosterone, calcium and alkaline phosphatase. Calcium and creatinine were measured in 24-h urine. A Z score less than -1 was observed for the lumbar spine of 14 patients (23.3%), and for the femur of 24 patients (40%). Patients with a Z score less than -1 for the lumbar spine were older than patients with a Z score > or = -1 (45.7 vs 43.8 years) and presented higher values of alkaline phosphatase (71.1 +/- 18.2 vs 57.1 +/- 14.3 IU/l). Multiple regression analysis showed that a lower lumbar spine BMD was associated with higher values of alkaline phosphatase, lower calcium ingestion, a smaller body mass index (BMI), less frequent exercising, and older age. The patients with a Z score less than -1 for the femur were shorter than patients with a Z score > or = -1 (158.2 vs 161.3 cm). Multiple regression analysis showed that a lower femoral BMD was associated with lower BMI, higher alkaline phosphatase and caffeine intake, and less frequent exercising. A lower than expected BMD was observed in a significant proportion of premenopausal women and was associated with lower calcium intake, relatively lower physical activity and lower BMI. We conclude that the classical risk factors for osteoporosis may be present before ovarian failure, and their effect may be partly independent of estrogen levels.
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PMID:Risk factors for decreased bone density in premenopausal women. 945 65

Bone disease is a major cause of morbidity in end stage renal failure. This study is aimed to assess the prevalence of abnormal bone mineral density (BMD), measured by dual photon absorptiometry (DPA) in the renal transplant population. Subjects consisted of 110 patients followed up after transplantation for between 1 and 17 years. Variables analyzed included age, sex, ethic origin, years and type of dialysis prior to transplantation, date of transplant, total steroid dose, number of rejection episodes, use of Cyclosporin, and biochemical/hormonal variables such as serum calcium, phosphate, magnesium, alkaline phosphatase, creatinine, FSH, LH and PTH. Analysis of variance and chi square tests were performed to assess the differences between groups and Pearson correlation coefficients were obtained. The total steroid dose, year of birth, PTH level and duration since transplantation were correlated with BMD (p < 0.05). Despite the statistical significance, the degree of variability indicated by each of these variables was low revealed by multiple regression analysis. We conclude that although steroid therapy is a major contributor to the increase in osteoporosis in renal transplant patients, about two thirds of the parameters that can influence bone metabolism remain unexplained.
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PMID:Factors affecting bone mineral density in renal transplant patients. 1043 73

To further define the nonhuman primate as a model of the adult human skeleton, we explored the impact of growth, natural menopause, and osteoarthritis on bone mass, serum markers of bone turnover (osteocalcin and C-terminal telopeptide of type I collagen) and measures of skeletal relevance (PTH, 25-hydroxyvitamin D, total alkaline phosphatase, calcium, phosphorus, creatinine, and albumin). Fifty-eight female (aged 4-30 yr) rhesus macaques were defined as growing (G; n = 12; < or = 10 yr old), adult premenopausal (APre; n = 30; > 10 yr old; eumenorrheic, high serum estradiol and low FSH), or postmenopausal (Post; n = 16; amenorrheic for at least 1 yr, with low serum estradiol and high FSH). Total body and posterior-anterior spinal bone masses were lower in G than APre animals (P < 0.05). Post females had lower total body, distal radius, and spinal bone mass than premenopausal animals (P < 0.05). Osteocalcin was higher in Post than APre animals (P < 0.01). Other measures showed no relationship with menopausal status. In older monkeys, spinal osteoarthritis became common, causing increased dual-energy x-ray absorptiometry-measured bone mass in the lumbar spinal posterior-anterior projection. In conclusion, after natural menopause, rhesus monkeys have lower bone mass and higher skeletal turnover without alteration of the calcium-vitamin D axis. As such, they are an excellent model of human estrogen-depletion bone loss.
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PMID:Skeletal effects of aging and menopausal status in female rhesus macaques. 1056 63

To assess the safety and efficacy of oestriol in relieving post-menopausal symptoms 53 post-menopausal Japanese women with climacteric symptoms, 27 with natural menopause (group I) and 26 with surgically induced menopause (group II), received oral oestriol, 2 mg daily for 12 months. Clinical parameters including Kupperman index (KI) and the degree of satisfaction with symptomatic relief; serum concentrations of oestradiol, FSH and LH; serum lipids; blood pressure; bone mineral density, serum calcium (Ca), alkaline phosphatase (ALP), and urinary Ca were compared between the two groups. Oestriol improved KI in groups I and II by 49 and 80% respectively. Satisfaction with treatment was 85% in group I and 93% in group II. For both parameters, values were significantly different between groups I and II (P < 0.05 for both). Serum concentrations of oestradiol, FSH and LH changed in group I versus group II 6 months after initiation. A significant decrease in serum ALP and Ca/Cr was observed in group I at 6 months. Except for serum triglycerides, oestriol had no significant effect on lipids. Systolic and diastolic blood pressures were significantly decreased in group I at 3 months versus baseline. Slight vaginal bleeding occurred in 14.3% of group I. Histological evaluation of the endometrium in all women of group I and ultrasound assessment of the breasts following 12 months of oestriol treatment found normal results in all women. Therefore, oestriol appeared to be safe and effective in relieving symptoms of menopausal women. The beneficial biochemical effects of oestriol were marked in the natural menopause. Overall, oestriol may serve as a good choice for hormone replacement therapy to protect against other climacteric symptoms in post-menopausal women who do not need medication for osteoporosis or coronary artery disease.
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PMID:Safety and efficacy of oestriol for symptoms of natural or surgically induced menopause. 1078 46


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