Diuretic activity and toxicity study of the aqueous extract of Cola nitida seed on markers of renal function and electrolytes in rats.

BackgroundCola nitida is a plant, conventionally used in Africa in the treatment of various ailments such as migraine, morning sickness and indigestion. The aim of the present study was to explore the diuretic activity of the aqueous extract of C. nitida seed (AECONS) and alteration caused by its subchronic administration on the structure and function of the kidney of male Wistar rats. MethodsThe study was divided into diuretic and subchronic studies. Twenty-five male Wistar rats weighing between 140 and 180 g were divided into five groups of five rats each. The first 24 h of this study investigated the possible diuretic activity of C. nitida seed. Group I (the control) received 25 mL/kg of normal saline. Group II (the standard) received 20 mg/kg/day of furosemide. Groups III, IV, V received 400, 600 and 800 mg/kg/day of AECONS, respectively, and orally. Urine volume, pH, specific gravity and electrolytes were estimated in the samples of urine collected after 6 h of the study. From the second day onward and up to a period of 4 weeks, the rats in each group were given normal saline, furosemide and AECONS once daily as was done on the first day. At the end of the 4-week treatment period, blood and urine samples were collected for the determination of creatinine, urea, Na+, K+ and Cl- concentrations. Results The results of the diuretic study showed that the AECONS at all doses used and furosemide produced a significant increase in urine output with respect to the control group. AECONS also induced a significant increase in the urine concentrations of Na+, K+, Cl- in the experimental and standard groups when compared with the control group, except for group III which showed no significant variation in K+ concentration. In the subchronic study, AECONS caused a significant increase in the urine levels of Na+, K+, Cl- in the experimental and standard groups when compared with the control rats. The plasma Na+ concentration of groups IV and V was significantly lower than that of the control group. Photomicrographs of the kidneys of the experimental and standard groups revealed no significant alterations in the histology of their kidney tissues. Conclusions It is concluded that AECONS induced diuresis which is associated with increased Na+, K+ and Cl- loss in rats without any significant alteration in the structure of their kidneys.

Diuretic and anti-diuretic activities of the ethanol and aqueous extracts of Alismatis rhizoma.

ETHNOPHARMACOLOGICAL RELEVANCE: Alismatis rhizoma or Alisma orientale (Zexie in Chinese), the dried rhizome of Alisma orientale Juzepzuk (Alismataceae), is a well-known traditional Chinese medicine and is used as an agent for diuresis and for excreting dampness in Asia and Europe. In this paper, we report the diuretic activities of the ethanol extract (EE) and the aqueous extract (AE) of A. rhizoma (AR). MATERIALS AND METHODS: The EE and AE were orally administered to rats. The urinary excretion rate and pH, and electrolyte excretion were measured in the urine of saline-loaded rats. RESULTS: The results showed that EE could increase the urine output at 2.5, 5 and 10mg/kg doses but decrease the urine output at 20, 40 and 80mg/kg doses compared with the control group. The 5 and 10mg/kg doses of EE increased the urine electrolyte excretion, but the effects on Na(+)/K(+) values were too weak to reach statistical significance. The Na(+) excretion and Cl(-) excretion were markedly decreased with the 20, 40 and 80mg/kg doses of EE, but the effect on K(+) excretion was notably slight. All of the tested doses of AE produced an increase in urinary excretion, but the increase did not reach statistical significance. CONCLUSIONS: This study identified that EE but not AE presents a notable diuretic effect, and EE had diuretic and anti-diuretic effects, which appears to be related to the sodium-chloride co-transporter in the renal distal convoluting tubule. This study demonstrated for the first time that the EE of AR has a dual effect on renal function, including promotion of diuretic activity at lower doses and inhibiting diuretic activity at higher doses, and the AR dose should be given more attention in clinical applications. This study will play a critical and guiding role in the dosing of AR as a diuretic drug in clinical applications.

Application of electrolysis for detoxification of an antineoplastic in urine.

Antineoplastics in excreta from patients have been considered to be one of the origins of cytotoxic, carcinogenic, teratogenic, and mutagenic contaminants in surface water. Recent studies have demonstrated that antineoplastics in clinical wastewater can be detoxified by electrolysis. In this study, to develop a method for the detoxification of antineoplastics in excreta, methotrexate solution in the presence of human urine was electrolyzed and evaluated. We found that urine inhibits detoxification by electrolysis; however, this inhibition decreased by diluting urine. In urine samples, the concentrations of active chlorine generated by anodic oxidation from 0.9% NaCl solution for inactivation of antineoplastics increased in dilution-dependent and time-dependent manner. These results indicate that electrolysis with platinum-based iridium oxide composite electrode is a possible method for the detoxification of a certain antineoplastic in urine.

Exercise but not mannitol provocation increases urinary Clara cell protein (CC16) in elite swimmers.

Elite swimmers have an increased risk of developing asthma, and exposure to chloramine is believed to be an important trigger factor. The aim of the present study was to explore pathophysiological mechanisms behind induced bronchoconstriction in swimmers exposed to chloramine, before and after swim exercise provocation as well as mannitol provocation. Urinary Clara cell protein (CC16) was used as a possible marker for epithelial stress. 101 elite aspiring swim athletes were investigated and urinary samples were collected before and 1 h after completed exercise and mannitol challenge. CC16, 11ß-prostaglandin (PG)F(2α) and leukotriene E(4) (LTE(4)) were measured. Urinary levels of CC16 were clearly increased after exercise challenge, while no reaction was seen after mannitol challenge. Similar to CC16, the level of 11ß-PGF(2α) was increased after exercise challenge, but not after mannitol challenge, while LTE(4) was reduced after exercise. There was no significant difference in urinary response between those with a negative compared to positive challenge, but a tendency of increased baseline levels of 11ß-PGF(2α) and LTE(4) in individuals with a positive mannitol challenge. The uniform increase of CC16 after swim exercise indicates that CC16 is of importance in epithelial stress, and may as such be an important pathogenic factor behind asthma development in swimmers. The changes seen in urinary levels of 11ß-PGF(2α) and LTE(4) indicate a pathophysiological role in both mannitol and exercise challenge.

Fractional excretion of K, Na and Cl following furosemide infusion in healthy, young and very old people.

UNLABELLED: Furosemide test is a simple and useful test of renal physiology used to evaluate the capability of the collecting ducts to secrete potassium under the effect of serum aldosterone. Its behaviour pattern has been established in children and young adults but not described in very old healthy people, which we explored in this study. MATERIAL AND METHODS: Twenty-six healthy volunteers on a standard Western diet (50 mmol of K/day) were studied: 20 of them were young (between 17 and 40 years old) and the rest were very old (between 75 and 85 years old). They suffered from no diseases and were not on any medication. Before, during the test and 180 min after a single dose of intravenous furosemide (1 mg/kg), urine and blood samples were obtained for creatinine and electrolytes levels. From these data we calculated fractional excretion (FE) of electrolytes; serum aldosterone was measured pre and post furosemide infusion. Statistical analysis was performed by applying Student's t-test. RESULTS: There was no significant difference regarding pre-furosemide (basal) FE of potassium between the very old and young group. Post-furosemide average FE of potassium was significantly lower in the very old group (27.4 +/- 2%) compared with the young group (35.4 +/- 9%) (P = 0.04). Even though there was no significant difference in post-furosemide peak FE of potassium value, it was reached later in the very old (120 min) compared with the young (30 min). Serum aldosterone levels were significantly higher post furosemide in both groups: 18.3 +/- 12.2 ng/dl (pre) versus 32.5 +/- 18.6 ng/dl (post) in the young (P = 0.007) and 69.8 +/- 13.7 ng/dl (pre) versus 113.3 +/- 54.8 ng/dl (post) in the very old (P = 0.04). Furthermore, all serum aldosterone values (pre and post furosemide) were significantly higher in very old people compared with young people (P < 0.001). Basal fractional excretion of sodium and chloride were slightly higher in the very old group compared with the young group (P = 0.05). Average post-furosemide FE of sodium and chloride were slightly and significantly lower in the very old (P = 0.05 and P = 0.03), respectively. However, there was no significant difference in peak post-furosemide FE of sodium and chloride values, which were reached later in the very old (120 min) compared with the young (30 min). CONCLUSION: Furosemide test showed a significantly lower average post-furosemide FE of potassium value, delayed post-furosemide peak FE of Na, K and Cl and a hormonal pattern of aldosterone resistance in very old people.

Uncovering the basis of a severe degree of acidemia in a patient with diabetic ketoacidosis.

In this teaching exercise, the goal is to demonstrate how an application of principles of physiology can reveal the basis for a severe degree of acidaemia (pH 6.81, bicarbonate <3 mmol/l (P(HCO(3))), PCO(2) 8 mmHg), why it was tolerated for a long period of time, and the issues for its therapy in an 8-year-old female with diabetic ketoacidosis. The relatively low value for the anion gap in plasma (19 mEq/l) suggested that its cause was both a direct and an indirect loss of NaHCO(3). Professor McCance suggested that ileus due to hypokalaemia might cause this direct loss of NaHCO(3), and that an excessive excretion of ketoacid anions without NH(4)(+) in the urine accounted for the indirect loss of NaHCO(3). In addition, he suspected that another factor also contributing to the severity of the acidaemia was a low input of alkali. He was also able to explain why there was a 16-h delay before there was a rise in the P(HCO(3)) once therapy began. The missing links in this interesting story, including a possible basis for the hypokalaemia, emerge during the discussion between the medical team and Professor McCance.

Tissue residues, metabolism, and excretion of radiolabeled sodium chlorate (Na[36Cl]O3) in rats.

A novel preharvest technology that reduces certain pathogenic bacteria in the gastrointestinal tracts of food animals involves feeding an experimental sodium chlorate-containing product (ECP) to animals 24-72 h prior to slaughter. To determine the metabolism and disposition of the active ingredient in ECP, four male Sprague-Dawley (approximately 350 g) rats received a single oral dose of sodium [36Cl]chlorate (3.0 mg/kg body weight). Urine, feces, and respired air were collected for 72 h. Radiochlorine absorption was 88-95% of the administered dose, and the major excretory route was the urine. Parent chlorate was the major species of radiochlorine present in urine at 6 h (approximately 98%) but declined sharply by 48 h (approximately 10%); chloride was the only other species of radiochlorine detected. Except for carcass remains (4.6% of dose), skin (3.2%), and gastrointestinal tract (1.3%), remaining tissues contained relatively low quantities of radioactivity, and >98% of radiochlorine remaining in the liver, kidney, and skeletal muscle was chloride. Chlorite instability was demonstrated in rat urine and bovine urine. The previously reported presence of chlorite in excreta of chlorate-dosed rats was shown to be an artifact of the analytical methods employed. Results from this study indicate that chlorate is rapidly absorbed and reduced to chloride, but not chlorite, in rats.

Effect of sodium [36Cl]chlorate dose on total radioactive residues and residues of parent chlorate in beef cattle.

The objectives of this study were to determine total radioactive residues and chlorate residues in edible tissues of cattle administered at three levels of sodium [36Cl]chlorate over a 24-h period and slaughtered after a 24-h withdrawal period. Three sets of cattle, each consisting of a heifer and a steer, were intraruminally dosed with a total of 21, 42, or 63 mg of sodium [36Cl]chlorate/kg of body weight. To simulate a 24-h exposure, equal aliquots of the respective doses were administered to each animal at 0, 8, 16, and 24 h. Urine and feces were collected in 12-h increments for the duration of the 48-h study. At 24 h after the last chlorate exposure, cattle were slaughtered and edible tissues were collected. Urine and tissue samples were analyzed for total radioactive residues and for metabolites. Elimination of radioactivity in urine and feces equaled 20, 33, and 48% of the total dose for the low, medium, and high doses, respectively. Chlorate and chloride were the only radioactive chlorine species present in urine; the fraction of chlorate present as a percentage of the total urine radioactivity decreased with time regardless of the dose. Chloride was the major radioactive residue present in edible tissues, comprising over 98% of the tissue radioactivity for all animals. Chlorate concentrations in edible tissues ranged from nondetectable to an average of 0.41 ppm in skeletal muscle of the high-dosed animals. No evidence for the presence of chlorite was observed in any tissue. Results of this study suggest that further development of chlorate as a preharvest food safety tool merits consideration.

Quantitative evaluation of renal function in healthy Beagle puppies and mature dogs.

Daily urinary collection and assessment of glomerular filtration rate (GFR) and effective renal plasma flow were performed in ten 2-month-old Beagle puppies and ten 6-9 year-old Beagle dogs to identify age-associated differences in renal function. The most striking differences in puppies compared to mature dogs were a higher daily urinary volume (+65%), GFR (+87%), free water reabsorption (+159%), a lower daily protein excretion (-88%), and fractional excretion of phosphorus (-35%). Renal function in Beagle puppies, but not mature dogs, was also quite different compared to data published in younger adult dogs.

Tissue distribution, elimination, and metabolism of dietary sodium [36Cl]chlorate in beef cattle.

Two steers (approximately 195 kg) were each dosed with 62.5 or 130.6 mg/kg body weight sodium [36Cl]chlorate for three consecutive days. All excreta were collected during the dosing and 8 h withdrawal periods. The apparent radiochlorine absorption was 62-68% of the total dose with the major excretory route being urine. Parent chlorate was 65-100% of the urinary radiochlorine; chloride was the only other radiochlorine species present. Similarly, residues in edible tissues were composed of chloride and chlorate with chloride being the major radiolabeled species present. Chlorate represented 28-57% of the total radioactive residues in skeletal muscle; in liver, kidney, and adipose tissues, chlorate ion represented a smaller percentage of the total residues. Chlorate residues in the low dose steer were 26 ppm in kidney, 14 ppm in skeletal muscle, 2.0 ppm in adipose tissue, and 0.7 ppm in liver. These data indicate that sodium chlorate may be a viable preharvest food safety tool for use by the cattle industry.

Effect of volcanic gas exposure on urine, blood, and serum chemistry.

AIMS: This pilot study tested the hypothesis that aluminium (Al), rubidium (Rb), arsenic (As), lead (Pb), mercury (Hg), fluorine (F), and chlorine (Cl), which are all known to be present in volcanic emissions, may be useful biological markers for occupational gas exposure in volcanologists. METHODS: Ten human subjects were exposed to fumarole gases on White Island, New Zealand, for approximately 20 minutes. Sulphur dioxide (SO2) exposure was recorded by personal monitoring tubes. Pre- and post-exposure urine, blood and serum samples (collected using standard protocols) were analysed in the pathology laboratory for trace element and halogen content. RESULTS: Average personal exposure was measured at <75 ppm SO2 and calculated at approximately 25 ppm HCl, approximately 8 ppm hydrogen fluoride (HF), approximately 1 ppm Al, approximately 0.1 ppb Rb and approximately 4 ppb Pb. These concentrations almost certainly exceed those usually found in occupational exposure settings. Advanced levels of urinary Al and Rb were found following gas exposure and were statistically significant in the population at p<0.005 and p<0.001, respectively. The other chemical elements that were analysed (urinary Cl, F, and Hg; blood Pb, and serum Al) did not show such patterns. CONCLUSIONS: It is possible that urinary Al and Rb may be useful markers for exposure, a hypothesis which should be followed up in future work.

Rapid natriuretic action of aldosterone in the rat.

Rapid, nongenomic actions of aldosterone have been demonstrated in a number of cell types in vitro, including renal cell lines, but there remains little direct evidence that it is able to exert rapid effects on the kidney in the whole animal. Accordingly, the aim of this study was to determine whether aldosterone induces rapid changes in the renal handling of electrolytes or acid-base balance in the anesthetized rat. With the use of a servo-controlled fluid replacement system, spontaneous urine output by anesthetized male Sprague-Dawley rats was replaced with 2.5% dextrose. After a 3-h equilibration and a 1-h control period, rats were infused with aldosterone (42 pmol/min) or vehicle for 1 h. Aldosterone infusion induced a rapid (within 15 min) increase in sodium excretion that peaked at 0.24 +/- 0.08 compared with 0.04 +/- 0.01 micromol x min(-1) 100 x body weight(-1) (P = 0.041) in the vehicle-infused rats. This natriuresis was not associated with changes in glomerular filtration rate; urine flow rate; potassium, chloride, or bicarbonate excretion; or urine pH. The mechanisms involved are unclear, but because we have previously shown that aldosterone stimulates a rapid (4 min) increase in cAMP generation in the rat inner medullary collecting duct (IMCD) (Sheader EA, Wargent ET, Ashton N, and Balment RJ. J Endocrinol 175: 343-347, 2002), they could involve cAMP-mediated activation of the cystic fibrosis transmembrane conductance regulator chloride channel, which drives sodium secretion in the IMCD.

X-ray fluorescence determination of the loss of chosen electrolytes in the urine of children with a congenital cyanotic heart defect and after heart transplantation.

In this paper results of the analysis of urine samples of healthy children and children with a congenital cyanotic heart defect and after heart transplantation are presented. The analysis of urine samples was carried out by X-ray fluorescence spectrometry with wavelength dispersion and using CRM urine Seronorm as a reference. It was found that for patients with a congenital cyanotic heart defect the loss of electrolytes like Na, Cl and K was increased. Moreover, urine samples of children from areas of different degree of environmental pollution were analysed. We observed (as expected) higher concentrations of heavy metals in the urine of children from ecological polluted areas.

Renal function following sea snake venom (Lapemis hardwicki) administration in dogs treated with sodium bicarbonate solution.

The effects of sea snake venom (SSV) on renal function were studied in two groups of anesthetized experimental dogs pretreated with intravenous infusion of 4.2 gm% NaHCO3 solution. Animals were envenomated by intramuscular injection of SSV at a dosage of 0.34 mg/kg. Systemic hemodynamics showed no significant changes except for a tendency of decrease in cardiac output (CO). The glomerular filtration rate (GFR), the rate of urine flow (V) and effective renal plasma flow (ERPF), and effective renal blood flow (ERBF) significantly decreased, while filtration fraction (FF) significantly increased at 180 min after envenomation. Envenomated animals showed a reduction in renal fraction (RF), while renal vascular resistance (RVR) increased stepwise throughout the experimental periods. Animals pretreated with sodium bicarbonate showed no significant changes of CO, TPR MAP, HR, and packed cell volume (PCV) while receiving sea snake venom. Animals pretreated with sodium bicarbonate showed no changes in GFR, ERPF, ERBF, RF, and RVR after envenomation. The rate of urine flow markedly increased in envenomated animals which received pretreatment with bicarbonate. After envenomation alone, there were no differences in the plasma concentration of sodium (PNa) and chloride (PCl) as compared to the control value, whereas the plasma concentration of potassium (PK) increased at 180 min after envenomation. Animals pre-treated with bicarbonate showed a stepwise increase in both UNaV, FE(NA), U(Cl)V, and FE(Cl) accompanying SSV injection. Neither PNa nor PCl were affected, while PK significantly decreased in animals given SSV with bicarbonate loading. UKV and FEK increased stepwise in envenomated animals treated with bicarbonate throughout the period of study. All groups of animals given SSV, with or without NaHCO3 infusion, showed a marked elevation of the concentration of urinary myoglobin (U(Mb)), plasma lactate dehydrogenase (LDH), and plasma creatine phosphokinase (CPK) throughout experimental periods. The urinary myoglobin excretion markedly increased in animals after SSV injection accompanied by NaHCO3 infusion. It can be concluded that large amounts of myoglobin present in the renal tubules in envenomated animals can precipitate, particularly under acidic conditions, resulting in increased intratubular pressure and subsequently decreased renal hemodynamics including GFR and ERBF. An infusion of NaHCO3 to render urine more alkaline could have a protective role against depression of renal function following sea snake venom administration.

Directly coupled liquid chromatography with inductively coupled plasma mass spectrometry and orthogonal acceleration time-of-flight mass spectrometry for the identification of drug metabolites in urine: application to diclofenac using chlorine and sulfur detection.

We report the application of high-performance liquid chromatography (HPLC) linked to inductively coupled plasma mass spectrometry (ICPMS) and orthogonal acceleration time-of-flight mass spectrometry (oa-TOFMS) for the identification of phase I and II urinary metabolites of diclofenac. The metabolites were separated by reversed-phase HPLC monitored with a UV diode array detector (UV-DAD) after which 90% of the eluent was directed to an ICPMS source, with the remainder going to an oa-TOF mass spectrometer. Compounds containing (35)Cl, (37)Cl and (32)S were detected specifically using ICPMS and identified by oa-TOFMS. The metabolites detected and identified in this way included glucuronic acid and sulfate conjugates, mono- and dihydroxylated and free diclofenac. In addition a previously unreported in vivo metabolite, an N-acetylcysteinyl conjugate of diclofenac, was also characterised. This is the first application of the combination of HPLC/UV-DAD/ICPMS/oa-TOFMS for the investigation of the metabolic fate of chlorinated xenobiotics by direct biofluid analysis.

Quantitative urinalysis in healthy Beagle puppies from 9 to 27 weeks of age.

UNLABELLED: To evaluate indices of renal function in healthy, growing Beagle puppies from 9 to 27 weeks of age and to determine whether indices change with age during this period. Animals-6 healthy Beagle puppies. PROCEDURE: Urine collections were performed at 2-week intervals in puppies 9 to 27 weeks old. Daily excretion of urinary creatinine, protein, sodium, potassium, chloride, phosphorus, and calcium were determined, as were quantitative urinalyses including endogenous creatinine clearance, urine protein-to-creatinine ratios (UPr/C), and fractional clearances of sodium (FNa), potassium (FK), chloride (FCI), calcium (FCa), and phosphorus (FP). RESULTS: Significant differences among age groups were detected for endogenous creatinine clearance, and daily urinary protein, potassium, calcium, and phosphorus excretion. Significant differences also existed among age groups for UPr/C, FNa, FK, FCI and FP. Age-related effects fit a linear regression model for FNa, UPr/C, daily phosphorus excretion, and daily protein excretion. Quadratic regression models were judged most appropriate for endogenous creatinine clearance, FK, daily chloride excretion, and daily potassium excretion. Endogenous creatinine clearance measurements higher than adult reference ranges were observed from 9 to 21 weeks of age. The FNa, FK, FCI, FCa, and FP were slightly higher than those reported for adult dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Selected results of quantitative urinalyses in healthy 9- to 27-week-old Beagle puppies differ with age and differ from those measured in adult dogs. Diagnostic measurements performed in puppies of this age range should be compared with age-matched results when possible.

The pathogenesis of dysplastic kidney in a urinary tract obstruction in the female fetal lamb.

BACKGROUND/PURPOSE: The type of renal dysplasia resulting from obstructive uropathy depends on the completeness of the obstruction and its timing with respect to the stage of glomerulogenesis at the time of the obstruction. The authors created a successful obstructive uropathy model in the female fetal lamb to demonstrate the differing pathogenesis of renal dysplasia. METHODS: Female fetal lambs at 60 and 90 days' gestation had their urethra and urachus ligated transabdominally and were delivered by cesarean section at 145 days (full term). Kidney length and cortical thickness were measured, and samples were examined histologically. In the lambs operated on at 90 days, the urine was collected at delivery and Na and CI were measured and compared with the results obtained from normal full-term lambs. RESULTS: Seven of 10 female lambs had hydronephrosis or dysplastic kidneys. The cortext to kidney length ratio was 10+/-3% in the 90-days hydronephrotic group versus 29+/-6% in the controls (P<.001). Morphologically, the 90-day model had dilatation of the collecting tubules with normal glomerular numbers. The 60-day model had tubular cysts with fibromuscular cuffing and reduced glomerular numbers. The fetal urine Na was 47+/-3.3 mmol/L in controls versus 78+/-24 mmol/L in the hydropnephrotic lambs (P<.05). The urine CI in these lambs was 38+/-8.6 mmol/L in controls versus 55+/-14.5 mmol/L in the hydronephrotic lambs (P<.05). CONCLUSIONS: An obstructive uropathy model was created in female fetal lambs. There were no dysplastic changes in the kidneys in lambs operated on at 90 days' gestation, but there were definite dysplastic changes in those operated on at 60 days. Concentrations of Na and CI in the fetal urine are higher than normal in the 90-day model.

The effect of combined oestrogen and progesterone replacement on the renal responses to oxytocin and vasopressin in ovariectomized rats.

OBJECTIVE: Renal responsiveness to the neurohypophyseal hormones, oxytocin and vasopressin, has been shown in the rat to vary during pregnancy and lactation. A study was performed to determine whether ovarian steroids could contribute to the observed changes. DESIGN: Using a previously validated method, fluid excretion during infusion of oxytocin or vasopressin was monitored in ovariectomized animals with and without chronic administration of oestrogen and progesterone. METHODS: After 14 days treatment with vehicle or 12.5 mg hydroxyprogesterone caproate and 0.25 mg oestradiol valerate injected every 3 days, rats were infused with 0.077 mol/l NaCl for an equilibration period of approximately 2.5h. Timed urine collections for the determination of volume and electrolytes were then made during a control period of at least 45 min and for 60 min while the infusate was supplemented with vasopressin (40 fmol/min) or oxytocin (50 fmol/min). Further observations were made for a final 90 min of hypotonic saline infusion. In control infusions saline alone was given. RESULTS: Treatment with ovarian steroids did not affect the volume of urine excreted during hormone infusion. Electrolyte excretion, however, was affected with lower concentrations of sodium and chloride on oxytocin infusion being seen in the steroid-treated animals. During vasopressin infusion, peak electrolyte concentrations were also achieved later in this group of animals. CONCLUSION: The increased circulating concentrations of oestrogen and progesterone seen during pregnancy could contribute to variations in the natriuretic response to neurohypophyseal hormones observed in the rat.

Comportamiento endocrino-metabólico de las fracturas de tercio medio facial / Endocrine and metabolic behavior of the fractures of the medial facial third

Se valoran los resultados del comportamiento endocrino-metabólico en 40 pacientes con fracturas del tercio medio facial: 10 nasales, 20 maxilomalares, 2 Lefort I, 4 Lefort II y 4 Lefort III. Según el sexo, 34 pacientes correspondieron al sexo masculino y 6 al femenino. Cuantificamos en orina (muestras de 24 horas): cloruro, sodio, potasio, urea y creatinina; en el ionograma en sangre: cloro, sodio, y potasio; en la química sanguínea: glucosa, clacio, fósforo, urea y creatinina y hemograma con diferencial. Estas muestras se cuantificaron al llegar el paciente, a las 72 horas y a las 24 horas del posoperatorio inmediato. En todos los pacientes estudiados se mantuvo la estabilidad endocrino-metabólica, con excepción de aquéllos portadores de Lefort I, II y III, los cuales en la última muestra tomada presentaron alteraciones del sodio y potasio en el ionograma de orina y sangre (AU)

Comportamiento endocrino-metabólico de las fracturas de tercio medio facial / Endocrine and metabolic behavior of the fractures of the medial facial third

Se valoran los resultados del comportamiento endocrino-metabólico en 40 pacientes con fracturas del tercio medio facial: 10 nasales, 20 maxilomalares, 2 Lefort I, 4 Lefort II y 4 Lefort III. Según el sexo, 34 pacientes correspondieron al sexo masculino y 6 al femenino. Cuantificamos en orina (muestras de 24 horas): cloruro, sodio, potasio, urea y creatinina; en el ionograma en sangre: cloro, sodio, y potasio; en la química sanguínea: glucosa, clacio, fósforo, urea y creatinina y hemograma con diferencial. Estas muestras se cuantificaron al llegar el paciente, a las 72 horas y a las 24 horas del posoperatorio inmediato. En todos los pacientes estudiados se mantuvo la estabilidad endocrino-metabólica, con excepción de aquéllos portadores de Lefort I, II y III, los cuales en la última muestra tomada presentaron alteraciones del sodio y potasio en el ionograma de orina y sangre