Effects of an intravenous saline load on erythrocyte sodium transport in normal human subjects

1985 ◽  
Vol 69 (6) ◽  
pp. 709-712 ◽  
Author(s):  
Roberto Boero ◽  
Francesco Quarello ◽  
Cesare Guarena ◽  
Clelia Rosati ◽  
Giuseppe Piccoli
Keyword(s):  
Sodium Transport ◽  
Human Subjects ◽  
Extracellular Fluid ◽  
Saline Infusion ◽  
Nacl Solution ◽  
Percentage Decrease ◽  
Intravenous Saline ◽  
Normal Human ◽  
Erythrocyte Sodium

1. The effects of a 2 litre intravenous infusion of saline (0.9% NaCl solution) over 3 h on erythrocyte transmembrane sodium transport were studied in 12 normal human subjects. 2. After saline infusion a significant (P < 0.01) reduction of both outward Na+, K+ pump- and Na+, K+ cotransport-mediated Na+ effluxes was observed. The Na+, Li+ countertransport rate and the passive Na+ permeability did not change. 3. The incubation of the subjects' erythrocytes, obtained on a separate occasion, with their own plasma taken after the saline infusion, induced an inhibition of both Na+, K+ pump and Na+, K+ cotransport outward sodium fluxes. The percentage decrease after incubation was closely correlated with the percentage reduction induced by the saline infusion in vivo (r = 0.93 for the pump and r = 0.96 for cotransport; P < 0.01). 4. These data suggest that extracellular fluid volume expansion affects the release of circulating factors modulating sodium transport by the Na+, K+ pump and by Na+, K+ cotransport.

Bronchoprotective and bronchodilatory effects of deep inspiration in rabbits subjected to bronchial challenge

2001 ◽  
Vol 91 (6) ◽  
pp. 2511-2516 ◽  
Author(s):  
S. J. Gunst ◽  
X. Shen ◽  
R. Ramchandani ◽  
R. S. Tepper
Keyword(s):  
Human Subjects ◽  
Inhibitory Effect ◽  
Airway Responsiveness ◽  
Deep Inspiration ◽  
Contractile Apparatus ◽  
Airway Reactivity ◽  
Airway Response ◽  
Normal Human ◽  
Airway Responses

The effect of deep inspiration (DI) on airway responsiveness differs in asthmatic and normal human subjects. The mechanism for the effects of DI on airway responsiveness in vivo has not been identified. To elucidate potential mechanisms, we compared the effects of DI imposed before or during induced bronchoconstriction on the airway response to methacholine (MCh) in rabbits. The changes in airway resistance in response to intravenous MCh were continuously monitored. DI depressed the maximum response to MCh when imposed before or during the MCh challenge; however, the inhibitory effect of DI was greater when imposed during bronchoconstriction. Because immature rabbits have greater airway reactivity than mature rabbits, we compared the effects of DI on their airway responses. No differences were observed. Our results suggest that the mechanisms by which DI inhibits airway responsiveness do not depend on prior activation of airway smooth muscle (ASM). These results are consistent with the possibility that reorganization of the contractile apparatus caused by stretch of ASM during DI contributes to depression of the airway response.

Effect of erythromycin on gastric myoelectrical activity in normal human subjects

1992 ◽  
Vol 263 (1) ◽  
pp. G24-G28
Author(s):  
J. Chen ◽  
P. Yeaton ◽  
R. W. McCallum
Keyword(s):  
Human Subjects ◽  
Control Period ◽  
T Test ◽  
Average Score ◽  
Severe Nausea ◽  
Gastric Myoelectrical Activity ◽  
Myoelectrical Activity ◽  
Intravenous Saline ◽  
Clinical Responses ◽  
Normal Human

While a great deal of attention has been paid to the effect of erythromycin (Ery) on gastric contractility, its effect on gastric myoelectrical activity, which controls gastric motility, remains unknown. In this study, Ery (6 mg/kg) was infused intravenously in 14 normal human subjects (placebo controlled). Gastric myoelectrical activity was recorded using the surface electrogastrographic method. The electrogastrogram (EGG) recordings were analyzed using spectral analysis methods. It was found that the presence of the 2-4 cycles/min activity (normal slow wave frequency range) in the EGG was 51 +/- 19% in the first hour of the intravenous Ery infusion, which was significantly smaller (P less than 0.001, t test) than that (72 +/- 20%) during the corresponding control period (intravenous saline). This difference was, however, not quite significant (P = 0.067, t test) in the second hour after the infusions. The average score for nausea during Ery was 4.5 (0 for no nausea, 10 for the most severe nausea). We conclude that 1) intravenous Ery induces irregularities in the cutaneous EGG in normal human subjects; and 2) the noninvasive cutaneous EGG is an attractive method both for the investigation of the effects of pharmacological and prokinetic agents such as Ery on gastric myoelectrical activity in humans and for correlating clinical responses to changes in the EGG.

Platelet catecholamines and platelet function in normal human subjects

1987 ◽  
Vol 73 (1) ◽  
pp. 99-103 ◽  
Author(s):  
A. P. Wilson ◽  
C. C. T. Smith ◽  
B. N. C. Prichard ◽  
D. J. Betteridge
Keyword(s):  
Platelet Function ◽  
High Performance ◽  
Human Subjects ◽  
Normal Subjects ◽  
Noradrenaline Content ◽  
Collagen Concentration ◽  
Normal Human ◽  
Wall Interaction ◽  
Local Release

1. We have used high-performance liquid chromatography with electrochemical detection to measure plasma and platelet catecholamines in 24 normal subjects. 2. In the same subjects platelet function was assessed by measuring platelet aggregation in response to adenosine 5′-pyrophosphate, thrombin, adrenaline and collagen. Platelet sensitivity to prostacyclin was also examined. 3. Platelet noradrenaline showed a positive correlation with extent of aggregation induced by ‘low-dose’ collagen (1 μg/ml). No correlation was seen at the higher collagen concentration. 4. Platelet noradrenaline content also correlated with sensitivity of platelets to prostacyclin. High platelet noradrenaline concentrations appeared to result in decreased sensitivity to prostacyclin. 5. No other correlations were observed. 6. These data suggest that platelet noradrenaline rather than plasma levels may be involved in modifying platelet function in vivo. Local release of platelet catecholamines may affect the platelet/vessel wall interaction, the primary physiological step in platelet activation.

scholarly journals Spatial nonuniformity of the resting CBF and BOLD responses to sevoflurane: In vivo study of normal human subjects with magnetic resonance imaging

2008 ◽  
Vol 29 (12) ◽  
pp. 1390-1399 ◽  
Author(s):  
Maolin Qiu ◽  
Ramachandran Ramani ◽  
Michael Swetye ◽  
Robert Todd Constable
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Human Subjects ◽  
In Vivo Study ◽  
Resonance Imaging ◽  
Spatial Nonuniformity ◽  
Bold Responses ◽  
Normal Human

Lithium and erythrocyte membrane cation carrier studies in normal and manic depressive subjects

1977 ◽  
Vol 7 (2) ◽  
pp. 229-233 ◽  
Author(s):  
G. J. Naylor ◽  
A. Smith ◽  
L. J. Boardman ◽  
D. A. T. Dick ◽  
E. G. Dick ◽  
...  
Keyword(s):  
Erythrocyte Membrane ◽  
Human Subjects ◽  
Normal Subjects ◽  
Sodium Concentration ◽  
Manic Depressive Psychosis ◽  
Manic Depressive ◽  
Normal Human ◽  
Potassium Influx ◽  
Erythrocyte Sodium

synopsisChanges in the erythrocyte membrane cation carrier following lithium ingestion in normal human subjects were studied; ouabain sensitive potassium influx fell significantly during the lithium treated phase. Lithium was fed to rats and no change in erythrocyte Na-K ATPase was shown. These findings contrast with studies of lithium in manic depressive psychosis. The fluctuations in the erythrocyte membrane cation carrier were studied in 5 normal subjects over 12 weeks and the correlations between the parameters calculated. The erythrocyte sodium concentration correlated positively with the ouabain sensitive potassium influx. This too contrasts with findings in manic depressive psychosis.

The Changes in Erythrocyte Sodium Transport Early in Normal Human Pregnancy

1989 ◽  
Vol 76 (s20) ◽  
pp. 56P-56P
Author(s):  
S MacPhail ◽  
TH Thomas ◽  
R Wilkinson ◽  
JM Davison ◽  
N Dunlop
Keyword(s):  
Sodium Transport ◽  
Human Pregnancy ◽  
Normal Human ◽  
Erythrocyte Sodium

Age and sex differences of erythrocyte sodium pump activity in normal human subjects

1977 ◽  
Vol 76 (3) ◽  
pp. 399-401 ◽  
Author(s):  
Mabel Hokin-Neaverson ◽  
David A. Spiegel ◽  
William A. Burckhardt ◽  
James W. Jefferson
Keyword(s):  
Sex Differences ◽  
Sodium Pump ◽  
Human Subjects ◽  
Pump Activity ◽  
Normal Human ◽  
Erythrocyte Sodium ◽  
Age And Sex

The appearance of compound cilia in the nasal mucosa of normal human subjects following acute, in Vivo exposure to sulfur dioxide

1987 ◽  
Vol 42 (1) ◽  
pp. 155-165 ◽  
Author(s):  
Johnny L. Carson ◽  
Albert M. Collier ◽  
Shih-chin Hu ◽  
Craig A. Smith ◽  
Paul Stewart
Keyword(s):  
Sulfur Dioxide ◽  
Nasal Mucosa ◽  
Human Subjects ◽  
Normal Human

scholarly journals Lactitol, a new hydrogenated lactose derivative: intestinal absorption and laxative threshold in normal human subjects

1987 ◽  
Vol 57 (2) ◽  
pp. 195-199 ◽  
Author(s):  
Dharmaraj H. Patil ◽  
George K. Grimble ◽  
David B. A. Silk
Keyword(s):  
Side Effects ◽  
Maximum Dose ◽  
Human Subjects ◽  
Normal Subjects ◽  
Perfusion Technique ◽  
Double Blind ◽  
Gastrointestinal Side Effects ◽  
Normal Human ◽  
Jejunal Perfusion

1. In the first part of the study, the absorption of lactitol, a new disaccharide analogue of lactose, was studied using an in vivo jejunal perfusion technique in man. Intestinal uptake of lactitol from isotonic solutions containing 10, 30, 60, and 100 mmol lactitol/l was insignificant.2. In the second part of the study the laxative threshold of lactitol was determined and compared with that of sorbitol in a double-blind, randomized, cross-over study on twenty-one normal subjects. Laxative threshold was considered to be either the maximum dose tolerated without unacceptable diarrhoea or gastrointestinal side effects, or when the maximum dose in the study was reached. Increasing amounts of lactitol, sorbitol or placebo were administered in two divided doses each day until subjects developed diarrhoea or severe gastrointestinal side effects. The laxative threshold of lactitol (74 (SE 5) g/d) was similar to that of sorbitol (71 (SE 5) g/d).3. These findings indicate that lactitol is not absorbed by the human small intestine. Although diarrhoea or other gastrointestinal side effects occurred as the dose was increased, 40 g lactitol/d was well tolerated.

Acute effects of nifedipine administration in vivo on erythrocyte sodium transport in pregnancy-induced hypertension

1988 ◽  
Vol 20 ◽  
pp. 119
Author(s):  
AM Cugini ◽  
G Benedetti ◽  
RA Rabini ◽  
I Testa ◽  
AL Tranquilli ◽  
...  
Keyword(s):  
Sodium Transport ◽  
Pregnancy Induced Hypertension ◽  
Acute Effects ◽  
Induced Hypertension ◽  
Erythrocyte Sodium ◽  
In Pregnancy
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