Search PubMed⌕ Search

Biomedical subjects

T V Nguyen

Publications and source records attributed to T V Nguyen.

At least 73 records · Page 4Linked to original sources
PubMed1998

Contribution of membrane cholesterol to outer hair cell lateral wall stiffness.

The outer hair cell can be divided into three domains: the apex, the base, and the lateral wall. With the use of filipin, a polyene fluorescent antibiotic that binds to cholesterol, we found under fluorescence microscopy that the lateral wall membranes were less intensely stained than the apical and basal membranes. This difference in filipin fluorescence between the lateral walls and the ends diminished when cells were incubated in water-soluble cholesterol before staining, suggesting that exogenous cholesterol enters the lateral wall. Under confocal microscopy, we studied the incorporation pattern of a fluorescent cholesterol analogue, NBD-cholesterol. NBD-cholesterol did not stain the apical membranes whereas it intensely labeled the lateral wall. The micropipette aspiration technique was used to assess the effect of cholesterol on lateral wall stiffness. The lateral wall stiffness parameter of cells treated with water-soluble cholesterol (n = 23) was significantly higher than that of controls (n = 27): 0.76+/-0.24 (mean +/- SD) versus 0.46+/-0.10 (Student's t-test, p < 0.001). In conclusion, cholesterol has different distributions among outer hair cell membranes, and when water-soluble cholesterol is incorporated into the cells, the outer hair cell lateral wall stiffness parameter increases.

Affinity Labels↗
PubMed1998

Genetic and environmental correlations between bone formation and bone mineral density: a twin study.

Bone mineral density (BMD) and bone turnover are both heritable. Although bone turnover affects bone mass, it is not clear whether these parameters are under common genetic or environmental control. The relative contribution of genetic and environmental factors to the determination of an index of bone turnover, bone specific alkaline phosphatase (BSAP), and the extent of common genetic regulation with BMD, were examined in 97 female twin pairs, aged 50 +/- 15 years (mean +/- SD), consisting of 48 monozygotic (MZ) and 49 dizygotic (DZ) pairs. BSAP was analyzed by radioimmunometric assay. Bone mineral density (BMD) at the lumbar spine (LS) and femoral neck (FN) was measured by dual-energy X-ray absorptiometry. Twin resemblance for variable traits was assessed by intraclass correlation coefficients. Estimates of genetic and environmental components of variance were based on univariate and multivariate genetic models. As expected, BSAP in premenopausal women (9.8 +/- 4.3 microg/L) was significantly lower than in postmenopausal women (13.3 +/- 6.6 microg/L, p < 0.001), but similar to the subgroup of postmenopausal women on hormone replacement therapy (10.8 +/- 2.6 microg/L, p = 0.15). Although BSAP and BMD were correlated in a cross-sectional analysis (r = -0.35, p < 0.001 for LS-BMD; r = -0.16, p = 0.03 for FN-BMD), the intrapair difference in BSAP was not significantly correlated with the intrapair difference in BMD for MZ twin pairs. After adjustment for menopausal status, the intraclass correlation for BSAP was significantly higher in MZ than DZ twins (0.60 +/- 0.09 vs. 0.27 +/- 0.13, p = 0.03). Univariate model-fitting analyses indicated a heritability of 63% for BSAP, and 77% and 72% for lumbar spine and femoral neck BMD, respectively. By multivariate analyses, genes specifically influencing BSAP accounted for 16% of the total genetic variance in LS-BMD and 4% of the total genetic variance in FN-BMD. There was no evidence for shared environmental factors affecting BSAP and BMD. These findings indicate that BSAP and BMD are heritable and negatively correlated. However, the genetic loci influencing BSAP and BMD appear to be largely independent as are any environmental factors.

Adult↗
PubMed1998

Prevalence and demographic determinants of metronidazole resistance by Helicobacter pylori in a large cosmopolitan cohort of Australian dyspeptic patients.

BACKGROUND: The pre-treatment sensitivity of Helicobacter pylori to metronidazole is a key determinant of successful eradication therapy and should influence local choice of therapy. However, there are few data defining the prevalence of metronidazole resistance (MR) in Australia. AIM: To determine prospectively the prevalence and demographic determinants of MR in H. pylori isolates from a large and cosmopolitan cohort of dyspeptic patients in Sydney. METHODS: Consecutive dyspeptic patients undergoing endoscopy had gastric biopsies for histology, urease test and culture. Metronidazole resistance was determined by E-test after subculture. An MIC > 8 micrograms/mL defined MR. Patient age, gender, birthplace and history of previous nitroimidazole use were recorded. RESULTS: In 732 patients, H. pylori was present in 46.4%. Culture was successful in 81% and subculture for MR in 88% of these. In 237 evaluable patients the overall MR rate was 59.1%. Five patients had had prior triple therapy for H. pylori (of which four of five had MR). Therefore, the primary MR rate in the study population was 58.6% (136/232). MR was more prevalent in younger patients (p = 0.0002). The MR rate was 70.4% in patients 18-39 years, 66.7% in those aged 40-59 years and lowest (38.9%) in those 60 years or older (p = 0.002). The MR rate was highest in patients born in Southeast Asia (72.8%, 59/81) and significantly higher than in Australian born (48.1%, 26/54), or Southern European (46.2%, 24/52) born patients (p = 0.002). There was no gender difference. Logistic regression to determine the impact of each variable (birthplace, age and gender) on MR identified Southeast Asia birthplace as a factor associated with greater likelihood of harbouring an MR isolate (OR 1.88, p = 0.02). Southern European born patients had the lowest risk of MR (OR 0.70, p = 0.02) as did patients older than 60 years (OR 0.56, p = 0.04). A definite history of prior metronidazole use was infrequent and not predictive of MR. CONCLUSIONS: While a high rate of MR is not unexpected in patients born in developing countries, the high rate in Australian born patients is surprising and of concern. This may relate to the high local usage of nitroimidazoles as monotherapy and has important implications for the effectiveness of metronidazole containing triple therapies.

Adolescent↗
PubMed1998

How is whole body protein turnover perturbed in growth hormone-deficient adults?

Adult patients with GH deficiency have reduced lean body mass (LBM), muscle mass, and muscle strength, suggesting an underlying abnormality of protein metabolism. As acute GH administration has previously been reported to decrease protein oxidation and increase protein synthesis in GH-deficient (GHD) adults, we investigated whether the converse might occur in untreated GH deficiency by undertaking studies of whole body protein turnover in 10 GHD and 13 normal subjects using a 3-h primed constant infusion of 1-[13C]leucine. Dual energy x-ray absorptiometry was used to quantify LBM and fat mass (FM). In normal subjects, LBM was the major, independent determinant of leucine appearance (Ra; r=0.80; P=0.0009), leucine oxidation (r=0.81; P=0.0008), and leucine incorporation into protein (r=0.75; P= 0.003). However, in an analysis of covariance, FM was also a significant independent determinant of leucine Ra (P=0.002) and leucine incorporation into protein (P=0.003). After correcting for LBM and FM, GHD patients had significantly reduced rates of leucine Ra (109.9+/-4.4 vs. 125.5+/-3.7 micromol/min, respectively; P=0.02) and leucine incorporation into protein (87.0+/-3.9 vs. 100.3+/-3.3 mmol/ min; P=0.02) compared to normal subjects. There was no significant difference in the corrected rates of leucine oxidation between the two groups (22.9+/-1.3 vs. 25.2+/-1.0, GHD vs. normal; P=0.20). In summary, GHD adults have reduced rates of protein synthesis and protein breakdown, but normal rates of irreversible oxidative loss; these findings are discordant with what was predicted from the acute changes in protein metabolism observed with GH administration. We conclude that normalization of protein oxidation may be a homeostatic mechanism that operates to constrain protein loss in GHD adults.

Adipose Tissue↗
PubMed1998

Genetic and environmental contributions to the association between quantitative ultrasound and bone mineral density measurements: a twin study.

This study was designed to assess the relative contributions of genetic and environmental factors to the variation and covariation of quantitative ultrasound (QUS) measurements and their relationships to bone mineral density (BMD). Forty-nine monozygotic (MZ) and 44 dizygotic (DZ) female twins between 20 and 83 years of age (53 +/- 13 years, mean +/- SD) were studied. Digital (phalangeal) QUS (speed of sound [SOS]) and calcaneal QUS (broadband ultrasound attenuation [BUA] and velocity of sound [VOS]) were measured using a DBM Sonic 1200 ultrasound densitometer and a CUBA ultrasound densitometer, respectively. Femoral neck (FN), lumbar spine (LS), and total body (TB) BMD were measured using dual-energy X-ray absorptiometry. Familial resemblance and hence heritability (proportion of variance of a trait attributable to genetic factors) were assessed by analysis of variance, univariate, and multivariate model-fitting genetic analyses. In both QUS and BMD parameters, MZ twins were more alike than DZ pairs. Estimates of heritability for age- and weight-adjusted BUA, VOS, and SOS were 0.74, 0.55, and 0.82, respectively. Corresponding indices of heritability for LS, FN, and TB BMD were 0.79, 0.77, and 0.82, respectively. In cross-sectional analysis, both BUA and SOS, but not VOS, were independently associated with BMD measurements. However, analysis based on intrapair differences suggested that only BUA was related to BMD. Bivariate genetic analysis indicated that the genetic correlations between BUA and BMD ranged between 0.43 and 0.51 (p < 0.001), whereas the environmental correlations ranged between 0.20 and 0.28 (p < 0.01). While the genetic correlations within QUS and BMD measurements were significant, factor analysis indicates that common genes affect BMD at different sites. Also, individual QUS measurements appear to be influenced by some common sets of genes rather than by environmental factors. Significant environmental correlations were only found for BMD measurements and ranged between 0.50 and 0.65 (p < 0.001). These data suggest that QUS and BMD measurements are highly heritable traits. While it appears that there is a common set of genes influencing both QUS and BMD measurements, specific genes yet to be identified appear to have greater effects than that of shared genes in each trait.

Absorptiometry, Photon↗
PubMed1998

Bone loss, physical activity, and weight change in elderly women: the Dubbo Osteoporosis Epidemiology Study.

The present study examined the effects of physical activity, weight, and weight change on femoral bone loss in relation to age in elderly women. Baseline and follow-up measurements at an average interval of 2.7 years of femoral neck bone mineral density (BMD) were reanalyzed for 827 women who were part of the Dubbo Osteoporosis Epidemiology Study. Physical activity was assessed based on hours per day spent in each of various activities according to its expected oxygen consumption. The rate of loss of BMD progressively increased with age, i.e., -0.6+/-0.1, -1.1+/-0.2, and -2.1+/-0.6% per year (mean +/- SEM) for the 60-69, 70-79, and > or = 80 age groups, respectively (p < 0.001). After adjustment for age, physically inactive women lost more (-1.4+/-0.2% per year; p < 0.001), compared with physically active women (-0.5+/-0.3% per year, p = 0.15). Thinner women experienced more rapid bone loss, and women whose weight decreased (> or =5%) over the study period lost more bone (-1.7+/-0.4% per year) than those whose weight was stable (-0.8+/-0.1% per year) or increased (+0.1+/-0.3% per year, p < 0.01, analysis of variance). Furthermore, women whose BMD was high (>0.81 g/cm2) at baseline experienced greater loss (-1.1+/-0.2%) compared with those in the middle tertile (1.0+/-0.2%) or lowest tertile (-0.5+/-0.3%). Independent predictors of rate of bone loss included age, baseline BMD, weight, weight change, and physical activity; collectively these factors accounted for 13% of total variance of bone loss by multiple regression analysis. It is concluded that a physically active lifestyle and stable weight in the later decades of life may retard proximal femur bone loss and thus contribute to reduction of fracture risk.

Age Factors↗
PubMed1998

Quality of life in osteoporosis: reliability, consistency, and validity of the Osteoporosis Assessment Questionnaire.

OBJECTIVE: To determine the reliability, consistency, and clinical utility of the Osteoporosis Assessment Questionnaire (OPAQ), an AIMS2 based self-assessment questionnaire. METHODS: Reliability of individual questions, scales, and domains were evaluated in 40 subjects by test-retest and intraclass correlation coefficients and internal consistency by Cronbach's alpha. Construct validity was evaluated by disease state. The relationships between domains and scales were modeled by confirmatory factor analysis. RESULTS: Mean kappa (79 questions) and intraclass correlation (18 health scales) coefficients were 0.58+/-0.16 (mean+/-SD) and 0.82+/-0.07, respectively. Internal consistency was greater than 0.8 in all but 3 scales. Construct validity was confirmed. Patients with hip fracture recorded lower OPAQ scores than patients with vertebral fracture. Correlation and confirmatory factor analyses grouped the 18 health scales into 7 domains. CONCLUSION: These findings suggest that OPAQ is a reliable, consistent, and valid instrument capable of distinguishing hierarchy of functional loss in disease states in osteoporosis.

Aged↗
PubMed1997

Relationship of a novel polymorphic marker near the human obese (OB) gene to fat mass in healthy women.

The cloning of the murine obese (ob) gene and its human homologue has recently been reported. Mutations in the mouse ob gene result in hereditary obesity; however, the role of variations of OB in the regulation of bodyweight in humans has yet to be determined. The contribution of putative genetic variations in the human OB gene to total and regional fat mass in a normal twin population has been analyzed through linkage and association with a novel polymorphic marker, located in proximity to this gene. The polymorphic dinucleotide repeat, isolated from a P1 clone containing the human OB gene, was physically localized by long-range restriction mapping to within 30 kilobases of the OB locus. The marker was genotyped in a population of 47 healthy female/female dizygotic (DZ) twin pairs for which direct measures of central abdominal and whole body fat had been obtained by dual X-ray absorbtiometry. Possible linkage between the microsatellite marker and whole-body (p = 0.008), but not central abdominal (p = 0.09), fat deposits was indicated. No association between fat depot phenotype and marker genotype was detected. These results suggest that genetic variation in or close to the human OB gene may play a role in the size of body fat stores in healthy women.

Adipose Tissue↗
PubMed1997

Influence of handedness on calcaneal ultrasound: implications for assessment of osteoporosis and study design.

Calcaneal ultrasound has been increasingly studied for its potential in the assessment of osteoporotic fracture risk. The accuracy of such an assessment is, in part, dependent on the reproducibility of the measurement. This study examines the impact of handedness on ultrasound measurements [broadband ultrasound attenuation (BUA) and velocity of sound (VOS)] in the calcaneus. Two hundred and sixty-four subjects (57 men and 297 women) aged 51.1 +/- 13.6 years (mean +/- SD) were studied. For each subject, calcaneal ultrasound measurements were performed on both heels with a McCue CUBA ultrasound densitometer. Right-handed dominance (94.7%) was determined by structured interview. In men, BUA measurements were significantly higher on the dominant side: mean difference 4.1 +/- 1.5 dB/MHz (mean +/- SD; p = 0.009), equivalent to 4.2 +/- 1.5% and more than 4 times the average rate of annual change in BUA. The difference between sides was greater in young (< 50 years) than old men (> 50 years). Among the women, the difference was not statistically significant (0.7 +/- 0.9 dB/MHz; p = 0.4); however, it was significant in younger women (20-30 years) (99 +/- 4 vs 90 +/- 4 dB/MHz, p = 0.01). By contrast VOS did not differ between sides in either men or women irrespective of age. Within-subject standard deviation of BUA was 9.8 dB/MHz for men and 8.6 dB/ MHz for women and the component due to right and left difference was 8.4 dB/MHz for men and 6.9 dB/MHz for women. This variability of BUA between right and left heels could increase the false-positive rate by up to 28% for a cut-off of 2 SD below the mean. These data indicate that variation between left and right heel measurements of BUA is higher than that of random error measurements, particularly in men and younger, presumably more physically active subjects. Although VOS measurements were not side dependent, in the smaller number of studies examining VOS and fracture risk, VOS appears to have a weaker predictive power than BUA. Clinical and epidemiological studies involving calcaneal BUA measurements should standardize the side measured to either the dominant or non-dominant heel, to reduce within-subject variation and increase their power.

Adult↗
PubMed1997

The validity of posttraumatic stress disorder among Vietnamese refugees.

The aim of this study was to examine the validity of posttraumatic stress disorder (PTSD) among Vietnamese refugees. The study population included 74 Vietnamese refugees who had resettled in the metropolitan Boston area. The previously validated Harvard Trauma Questionnaire was used to assess traumatic events and trauma-related symptoms. The number of traumatic events experienced was positively correlated with the severity of PTSD-related symptoms in this population. Internal consistency estimates and principal components analysis provided results that generally supported DSM-IV symptom dimensions of arousal, avoidance, and reexperiencing. However, the emergence of two separate dimensions of avoidance reflected the important contribution of depression to the traumatic response.

Adult↗
PubMed1997

Independent genetic factors determine the amount and distribution of fat in women after the menopause.

Central adiposity is a strong predictor of cardiovascular disease in women. We studied postmenopausal twins to explore the strength and the relationship between genetic influences on body fat and its distribution in a group where cardiovascular disease is the major cause of mortality. Healthy twin women were recruited from a national media campaign. One hundred nineteen monozygotic (MZ) and 97 dizygotic twin pairs were studied (mean +/- SE age 60 +/- 0.3 yr; 10 +/- 0.4 yr post menopausal). Total and central body fat were measured by dual-energy x-ray absorptiometry. Intrapair resemblance was significantly greater in MZ pairs for total fat (MZ vs. dizygotic, r = 0.70 +/- 0.05 vs. r = 0.46 +/- 0.08, P = 0.005) and central fat (r = 0.62 +/- 0.06 vs. r = 0.35 +/- 0.09, P = 0.005), suggesting a strong genetic influence on these traits. Model-fitting analysis indicated that genetic factors contribute up to 60% of total population variance in both total and central body fat. The heritability of central fat remained, after adjustment for the heritability of total fat, suggesting an independent genetic influence on fat distribution. These results were unchanged after adjusting for the effects of estrogen replacement and smoking. In conclusion, total adiposity and central abdominal fat mass in normal postmenopausal women are under strong genetic influence. The data suggest that some of the genes responsible for central adiposity and its metabolic sequelae will be different from those responsible for total adiposity.

Adipose Tissue↗
PubMed1997

Sources of variability in bone mineral density measurements: implications for study design and analysis of bone loss.

Measurement of bone mineral density (BMD) is a useful tool for monitoring efficacy in osteoporosis therapy. However, the ability to detect true change for a subject as well as for a group of subjects is dependent on the precision of the measurement. In this paper, short-term and long-term reliability of bone mass measurements were examined at the spine and femoral neck using dual-photon and dual-energy X-ray absorptiometry and related to guidelines for study design. The concepts involved in these analyses are relevant to a study for any therapy involving a quantitative trait. Short-term reliability was assessed by repeated measures in 60 subjects aged 46 +/- 9 years (mean +/- standard deviation [SD]), and in 32 elderly subjects (aged 75 +/- 5 years), on the same day with repositioning. Long-term variability in the rate of linear changes in BMD was assessed in a cohort of 293 women and 184 men, aged 60+, each having BMD measured on three separate occasions over an average interval of 2 years. Short-term variability in BMD was assessed using the coefficient of reliability (R) and standard deviation (SD) of measurement error. Long-term variability in BMD was modeled by linear regression. In the younger sample, the SD of measurement error for the lumbar spine and femoral neck was 14 and 25 mg/cm2, respectively, yielding coefficients of reliability for short-term measurements of 0.99 and 0.97, respectively. In the elderly sample, the coefficient of reliability was 0.96 and 0.77 for lumbar spine and femoral neck, respectively. For long-term variability, for which a linear rate of change in BMD was assumed, the SD of intrasubject variation in the women was 42 mg/cm2 at both the lumbar spine and femoral neck and in men 57 and 42 mg/cm2, respectively. The between-subject SD of the rates of change was higher in males than females (21 and 14 mg/cm2/year, respectively; p = 0.037). Importantly, intrasubject estimation error contributed about 90% of the variability component. These sources of variability lead to reduction in the power of a study and underestimation of the relative risk in logistic regression relating BMD and fracture risk in population studies. At the individual level, they increase the false-positive and false-negative error rates of diagnostic BMD and present major difficulties in the assessment of bone loss. The measurement error can be reduced by taking multiple measurements per visit. However, long-term intrasubject variation can be reduced by increasing the length of follow-up and/or increasing the frequency of measurements and, in a study, by increasing the number of subjects. Modeling of these errors, study duration, and frequency of measurements indicates that studies with a duration of 3-5 years appear to have the optimum "cost-benefit," and making measurements more than twice a year does not improve the precision appreciably. These modeling approaches can be extended to other clinical studies involving quantitative measurements with measureable errors within and between individuals and contributes to rational selection of the duration and frequency of measurements.

Absorptiometry, Photon↗
PubMed1996

Risk factors for osteoporotic fractures in elderly men.

Osteoporosis is recognized as an important cause of morbidity and mortality in aging women, but there have been few epidemiologic studies in men. Potential risk factors for osteoporotic fractures were assessed in 220 elderly men aged 60 years or above in the city of Dubbo (Australia). During the follow-up period of 1989-1994, the overall incidence of fractures (determined from x-ray reports) was 220 fractures per 10,000 person-years. Higher risk of fracture was associated with lower femoral neck bone mineral density (BMD), quadriceps weakness, higher body sway, falls in the preceding 12 months, a history of fractures in the previous 5 years, lower body weight, and shorter current height. Use of thiazide diuretics, higher physical activity, and moderate alcohol intake were protective against fracture. In multivariate analysis (Cox's proportional hazards model), femoral neck BMD (odd ratio (OR) = 1.47, 95% confidence interval (CI) 1.25-1.73 per 0.12 g/cm2), quadriceps strength (OR = 1.43, 95% CI 1.18-1.73 per 10 kg), and body sway (OR = 1.25, 95% CI 1.07-1.45 per 5.15 cm2) were independent risk factors. Preventive measures for bone loss and maintaining a physically active, healthy life-style and modification of risk factors for falls in the elderly could yield beneficial effects in the reduction of the incidence of osteoporotic fracture and hence improve the survival among men.

Accidental Falls↗
PubMed1996

Screening for osteoporosis: what is the role of heel ultrasound?

Could focused population screening detect osteoporosis earlier and improve the management of this major health care problem? Quantitative ultrasound of the calcaneus is currently being proposed as a suitable screening technique. Correlations between quantitative ultrasound of the calcaneus and dual energy x-ray absorptiometry of bone mineral density of the spine and proximal femur are not high enough to reliably predict bone mineral density at the lumbar spine or proximal femur from the ultrasound results. Some ongoing longitudinal studies suggest that quantitative ultrasound may none the less detect individuals at increased risk of fracture, but its use for mass screening for osteoporosis would be premature.

Absorptiometry, Photon↗
PubMed1996

Short-term growth hormone (GH) treatment of GH-deficient adults increases body sodium and extracellular water, but not blood pressure.

Initiation of GH treatment in adults is frequently complicated by the development of symptomatic fluid retention. To investigate the mechanism and extent of fluid retention that occurs with dosages of GH used in the treatment of GH-deficient adults, we conducted a double blind study in which seven GH-deficient patients (aged 24-74 yr) each received in random order daily sc injections of placebo, a physiological dose of GH (0.04 U/kg, low dose), and a supraphysiological dose of GH (0.08 U/kg, high dose) for 7 days, separated by 21-day washout periods. On the seventh day, measurements were made of serum insulin-like growth factor I, body weight, exchangeable sodium, plasma volume, angiotensinogen, PRA, aldosterone, atrial natriuretic peptide (ANP), and mean 24-h ambulatory heart rate and blood pressure. GH significantly increased mean insulin-like growth factor I levels from 105 +/- 11 to 304 +/- 45 micrograms/L during low dose treatment (P = 0.006) and 400 +/- 76 micrograms/L during high dose treatment (P = 0.004). High dose GH caused a 1.2 +/- 0.3 kg increase in body weight (P = 0.01) and a 193 +/- 65 mmol increase in exchangeable sodium (P = 0.008). Low dose GH had a lesser effect, with no significant increase in body weight, but an increase in exchangeable sodium of 113 +/- 37 mmol (P = 0.02). Plasma volume was not significantly affected by GH treatment. Mean supine angiotensinogen levels were significantly higher during both GH treatments compared to placebo (low dose, P = 0.017; high dose, P = 0.028) as were mean supine PRA levels (low dose, P = 0.0002; high dose, P = 0.0025). Supine angiotensin II, aldosterone, and ANP levels were not significantly affected by GH treatment. There was no significant change from placebo in any of the sodium-regulating hormones in the erect posture. The mean 24-h heart rate was significantly higher during low dose (82 +/- 2 beats/min; P = 0.0001) and high dose (88 +/- 3 beats/min; P = 0.0001) GH treatment than during placebo (67 +/- 3 beats/min). However, no significant change in mean 24-h systolic or diastolic blood pressure was observed. In summary, acute GH administration using doses currently employed in treating adults causes a dose-related increase in body weight and body sodium, but no associated increase in blood pressure. We conclude that 1) sodium retention is a physiological effect of GH, but does not cause an acute rise in blood pressure; and 2) the mechanism of sodium and fluid retention is not primarily due to enhanced aldosterone secretion or inhibition of ANP release, but more likely to a direct renal tubular effect.

Adult↗