Functional heterogeneity of culture-grown bone marrow-derived macrophages. II. Lymphokine stimulation of antigen-presenting function

The activation of immunostimulatory activity and Ia expression was studied in pure populations of murine macrophages (M phi) grown in vitro from bone marrow precursor cells in the presence of L cell-conditioned medium as the source of colony-stimulating factor. During exponential growth, the M phi developed maximal Ia-dependent antigen-presenting activity as detected by the induction of antigen-specific T cell proliferation, but the proportion of Ia+ M phi was low (less than 10%). Fractionation of the M phi according to size by velocity sedimentation resulted in concentration of the antigen-presenting cells in the smallest fraction, but the enrichment of Ia+ M phi in this fraction was less than twofold. All fractions also showed comparable degrees of antigen uptake regardless of their T cell-stimulating activity. Thus Ia and antigen, although obviously essential, are insufficient for full manifestation of antigen-presenting function. Activation of M phi with lymphokines from Mycobacterium-activated lymph node cells resulted in enhanced Ia expression in all fractions, but only small M phi showed an enhancement in antigen presentation. Large activation M phi were found to exert an immunosuppressive effect that probably neutralized any augmentation of stimulatory activity. thus heterogeneity can be demonstrated in i) the function of unstimulated M phi, ii) the responsiveness of subsets to stimulation, and iii) the manifestation of activated functions.

Saxitoxin binding sites in frog-myocardial cytosol

Cytosolic fractions of frog heart homogenates contain large amounts of a soluble, large molecular weight protein that binds the specific neurotoxin saxitoxin with the same high affinity as does the plasma membrane. Another neurotoxin, tetrodotoxin, which ordinarily is competitive with saxitoxin, does not displace saxitoxin from the cytosolic sites or from plasma membrane-enriched vesicular fractions even when its concentration exceeds that of saxitoxin by a factor of 1000. Thus, cytosolic sites are similar to membrane sites in this respect. The vesicular fraction accounts quantitatively for the amount of saxitoxin bound by whole ventricles, so that no appreciable losses seem to occur. Therefore, the cytosolic site probably is a membrane site precursor, although other possibilities cannot be ruled out. In any case, the occurrence of a soluble molecule closely related to the sodium channel provides opportunities for further study of the structure of the sodium channel.

Intravenous dipyridamole combined with isometric handgrip for near maximal acute increase in coronary flow in patients with coronary artery disease

Twenty-four patients with coronary artery disease were studied during cardiac catheterization to determine the effects of sustained isometric handgrip exercise and intravenous dipyridamole and their combination on coronary and systemic hemodynamics and measured coronary luminal caliber. During 4 to 5 minutes of 25 percent maximal handgrip, blood pressure and heart rate increased 24 and 19 percent, respectively, coronary sinus flow increased to 1.7 x baseline value, and epicardial coronary arteries constricted to increase predicted flow resistance by 40 percent in 36 diseased arterial segments. After a 4 minute intravenous infusion of dipyridamole (0.56 mg/kg body weight), systemic pressure decreased 8 percent, heart rate increased 23 percent, coronary sinus flow increased to 2.4 x baseline value and coronary luminal caliber was unchanged. During isometric handgrip initiated 6 minutes after the infusion of dipyridamole, systemic pressure and heart rate increased to 14 and 31 percent, respectively, above control values, coronary sinus flow increased to 3.3 x baseline value (3.8 x baseline value in patients with normal anterior perfusion) and stenotic flow resistance increased by 36 percent. The response of coronary flow to the combined stresses was 68 percent greater than the response to dipyridamole alone (p less than 0.02); these flow levels exceed values previously reported for the human coronary circulation. Aminophylline plus nitroglycerin appears to assure patient safety.

Abnormal mitral valve coaptation in hypertrophic obstructive cardiomyopathy: proposed role in systolic anterior motion of mitral valve

Two dimensional echocardiographic evaluation utilizing the apical four chamber and apical long axis views was made in 10 normal subjects and 35 patients with hypertrophic cardiomyopathy, including 16 without and 19 with systolic anterior motion of the mitral valve. Mitral valve leaflets were imaged throughout the cardiac cycle. The normal subjects and the patients with hypertrophic cardiomyopathy without systolic anterior motion demonstrated mitral valve coaptation that seemed to involve the distal tip of the anterior leaflet. In contrast, patients with hypertrophic cardiomyopathy with systolic anterior motion demonstrated abnormal coaptation, so that the posterior leaflet coapted with a mid portion of the anterior leaflet, leaving a distal "residual" anterior leaflet in the left ventricle during systole. A sharp angulation of this distal leaflet in mid systole toward the interventricular septum is thought to represent systolic anterior motion. It is speculated that abnormal mitral leaflet coaptation in necessary for development of leaflet systolic anterior motion, which is correlated with dynamic left ventricular outflow gradients in hypertrophic obstructive cardiomyopathy.

Ring chromosome 14: a distinct clinical entity

An infant girl with ring chromosome 14 is presented. The findings in this patient and in six previously reported cases of a ring 14 suggest that a characteristic clinical syndrome is associated with this chromosome aberration. The major features of the ring chromosome 14 syndrome include mental retardation, a disorder of skin pigmentation, seizures, and dysmorphic features, including flat occiput, epicanthal folds, downward slanting eyes, flat nasal bridge, upturned nostrils, short neck, and large low set ears.

Size and motion of the mitral valve annulus in man. I. A two-dimensional echocardiographic method and findings in normal subjects

Using wide-angle, phased-array, two-dimensional echocardiography, mitral leaflets and their annular attachments were recorded from a view close to the standard apical four-chamber view. The transducer was rotated and recordings were made at 30 degrees rotational intervals around the circumference of the mitral valve annulus. To reconstruct the annulus, the diameters (chords) from each rotational interval were arranged around a reference point. This was done for 12 times during the cardiac cycle. Annular areas were planimetered and circumferences measured. Correlation was good for areas reconstructed and measured by the same observer on separate occasions (r = 0.963) and by two different observers (r = 0.987). In 11 normal subjects the annular area index (area divided by body surface area) increased during diastole to a maximum of 3.8 +/- 0.7 cm2/m2 (mean +/- SD) in late diastole. There was presystolic followed by systolic narrowing to a minimum in midsystole. The mean reduction in area was 26 +/- 3%. The maximal annular circumference was 9.3 +/- 0.9 cm and the mean reduction in circumference was 13 +/- 3%. The overall motion pattern was similar to that reported in experimental studies in the dog. Mitral annular reconstruction may provide new information about normal and abnormal function of the mitral valve apparatus.

Reverse redistribution: worsening of thallium-201 myocardial images from exercise to redistribution

Reverse redistribution (RR) i.e., worsening of images from exercise to redistribution, was noted in 21 (7%) of 300 consecutive thallium-201 (201TI) exercise and redistribution myocardial imaging studies. In 13, there were reversible defects consistent with ischemia in addition to redistribution defects. Twenty RR defects were noted in 15 patients who underwent cardiac catheterization; 9 had triple, 4 had double and 2 had single vessel coronary artery disease. Seventeen (85%) of the RR defects were in the distribution of severely diseased vessels; 8 with 100% occlusion and 9 with 90-99% stenosis. The remainder were associated with 50-60% stenoses. Ten RR areas (50%) were supplied by collateral vessels and 3 (15%) by bypass grafts. Fourteen of the 18 (78%) areas studied with left ventriculography were associated with abnormally contracting segments. These results suggest that RR is a marker for significant coronary artery disease.

Characterization of macrophage subpopulations responsive to activation by endotoxin and lymphokines

The subpopulations of murine macrophages (M phi) that can be activated by endotoxin (LPS) and lymphokines to produce lymphocyte-activating factor, or interleukin 1 (IL-1), and to express cytostatic and cytolytic activities against tumor cells were characterized in 3 cell populations with immature and mature M phi in various proportions, namely, normal peritoneal cells, glycogen-induced peritoneal cells, and cultured bone marrow M phi. There is disagreement in the literature as to whether tumor cytotoxicity can be elicited from all M phi or from a subset of small, newly formed peroxidase-positive (p+) monocytes. Using the technique of cell size fractionation, which separates p+ and p- M phi to various extents, we have found that the magnitude of te response to LPS and lymphokines increases with cell size (and hence maturity or the degree of prior stimulation) and is not exclusive to p+ M phi. Our results are consistent with the concept that all M phi, irrespective of developmental stage, can exist in a continuum of activated states, depending on the nature of the activation signals.

Comparative evaluation of segmental asynergy in remote myocardial infarction by radionuclide angiography, two-dimensional echocardiography, and contrast ventriculography

Radionuclide angiography (RNA), two-dimensional echocardiography (2DE), and contrast ventriculography (CVG) were compared in the evaluation of regional wall motion (RWM) in 58 patients with remote myocardial infarction (MI). All 58 patients were studied by 2DE, 52 by RNA, and 24 by CVG. Severe degrees of segmental asynergy (akinesia/dyskinesia) were noted more often by 2DE (56% of all segments, p less than 0.005) and CVG (52%, p less than 0.05) than by RNA (39%). The apex more the most frequent site of akinesia/dyskinesia by all technique (43% by RNA, 36% by 2DE, and 45% by CVG). 2DE and RNA agreed in 64% of regions (p less than 0.005), 2DE and CVG agreed in 68% (p less than 0.005), and RNA and CVG agreed in 70% (p less than 0.005); the highest agreement was for the apical region. Dyskinesia was noted in 77% of patients by RNA, in 71% by 2DE, and 79% by CVG. RNA and CVG agreed in 89% of patients and in 57% of regions, 2DE and CVG agreed in 67% of patients and in 53% of regions, and RNA and 2DE agreed in 71% of patients and in 38% of regions. Combined RNA and 2DE detected dyskinesia in 94% of the 16 patients with dyskinesia by CVG who underwent all three techniques and in 90% of the 52 patients studied by RNA and 2DE. We conclude that (1) RNA, 2DE an CVG agree significantly in the evaluation of regional wall motion; (2) there is better agreement concerning the presence or absence of dyskinesia in a given patients than the exact region involved; and (3) the combination of RNA and 2DE is more useful than either alone as a screening procedure for the detection of ventricular dyskinesia.

Characterization of macrophage subpopulations responsive to activation by endotoxin and lymphokines

The subpopulations of murine macrophages (M phi) that can be activated by endotoxin (LPS) and lymphokines to produce lymphocyte-activating factor, or interleukin 1 (IL-1), and to express cytostatic and cytolytic activities against tumor cells were characterized in 3 cell populations with immature and mature M phi in various proportions, namely, normal peritoneal cells, glycogen-induced peritoneal cells, and cultured bone marrow M phi. There is disagreement in the literature as to whether tumor cytotoxicity can be elicited from all M phi or from a subset of small, newly formed peroxidase-positive (p+) monocytes. Using the technique of cell size fractionation, which separates p+ and p- M phi to various extents, we have found that the magnitude of te response to LPS and lymphokines increases with cell size (and hence maturity or the degree of prior stimulation) and is not exclusive to p+ M phi. Our results are consistent with the concept that all M phi, irrespective of developmental stage, can exist in a continuum of activated states, depending on the nature of the activation signals.

Reproducibility of left ventricular internal dimensions with M mode echocardiography: effects of heart size, body position and transducer angulation

Analysis was made of the variables of heart size, body position and transducer angle affecting the reproducibility of left ventricular internal dimensions as measured with M mode echocardiography. Echocardiograms were recorded in 24 subjects as the thorax was incrementally rotated and tilted. Transducer angle was noted from a three plane level attached to the probe. Constants were the technician, transducer placement and the interpreter. Heart rates varied insignificantly; respirations were held. Groups A and B were defined by their initial left ventricular internal dimensions at end-diastole (LVIDd): 49 +/- 5.9 and 73 +/- 8.6 mm (group mean +/- standard deviation). With body position constant the measurement error between duplicate recordings of LVIDd was +/- 1.2 mm (coefficient of variation = 1.8 percent) in Group A and +/- 4.5 mm (coefficient of variation = 4.6 percent) in Group B (p less than 0.001). Transducer angle varied 12 degrees between duplicate recordings in both groups. As the position of the thorax changed, the transducer followed, maintaining approximately the same incline with the chest wall. In both groups errors for combined LVIDd recorded with rotation and tilt, respectively, were unchanged from the duplication error. Thus, when the spatial orientation between the transducer and heart is held constant, it is the size of the heart that determines the reproducibility of the measurement of left ventricular internal dimensions.

Characterization of poly(ADP-ribose)--histone H1 complex formation in purified polynucleosomes and chromatin

Poly(ADP-ribose) [poly(ADP-Rib)] polymerase of HeLa nucleosomes has been shown in vitro, to catalyze the synthesis of a complex of histone H1 containing 2 H1 histones and 15-16 units of oligo(ADP-Rib). The synthesis of the H1 complex in vitro was compared in polynucleosome populations of various sizes (3--16 and greater than 30) released from HeLa nuclei following micrococcal nuclease digestion. Poly(ADP-Rib) was synthesized from [32P]NAD and the poly(ADP-ribosyl)ation of H1 was studied by selective H1 extraction, gel electrophoresis and autoradiography. Quantitative differences in H1 complex formation occurred when either chromatin concentration or polynucleosome length was varied. The data indicated that H1 complex formation in vitro was favored in polynucleosomes 16 nucleosomes long as compared to 8 nucleosomes. A series of partially ADP-ribosylated H1 species was also detected. Partially modified H1 species migrate more slowly than pure H1 in dodecylsulfate gels. The reduced mobility is a function of the number of attached ADP-Rib moieties. Thus, molecules containing one molecule of H1 and various numbers of ADP-Rib residues can be separated. When the partially modified H1 species were incubated in alkali to cleave the linkage of ADP-Rib to protein, (ADP-Rib1-15) were detected by chain length analysis on 15% polyacrylamide gels. The intermediate H1 species could be chased, in vitro, into as H1 complex with NAD and thus were determined to be successive precursors in the formation of the H1 complex. Evidence is presented that the H1 complex is synthesized in intact cells permeabilized with lysolecithin.

Immunohistochemical localization of IgA and secretory component in rat liver

IgA is transported from rat blood into bile. The localization of IgA and secretory component in rat liver was studied in order to facilitate understanding of this IgA transport. Both indirect immunofluorescence and unlabeled antibody enzyme histochemical techniques were used. Immunoglobulin A was found surrounding bile canaliculi, within bile duct epithelium, on or near the plasma membranes of hepatocytes, within the cytoplasm of a few intensely stained hepatocytes, within the cytoplasm of intensely reactive cells found in or adjacent to the sinusoids, and in sparsely distributed plasma cells. Reactivity for secretory component was present surrounding bile canaliculi, within bile duct epithelium, or or near the plasma membranes of hepatocytes and in the cytoplasm of hepatocytes. These findings are compatible with the hypothesis that immunoglobulin A is transported from blood to bile through hepatocytes by a process involving secretory component. Bile duct epithelium may also have a role in immunoglobulin A transport.

Antigenic relationships and rapid identification of Peptostreptococcus species

Antisera against whole cells of each Peptostreptococcus species (P. anaerobius, P. micros, P. parvulus, and P. productus) were produced in rabbits. When these antisera were reacted against sonically disrupted cells and culture supernatant fluids in Ouchterlony tests, lines of identity were obtained among the antigens from all the species and uninoculated culture medium. When the antisera were subsequently absorbed with the dehydrated culture medium used to grow the peptostreptococci, all cross-reactions in heterologous antigen-antibody combinations were eliminated, leaving only species-specific precipitin arcs. These absorbed antisera, specific for each Peptostreptococcus species by Ouchterlony tests, were used for rapid identification studies. Staphylococcus aureus-bearing protein A was sensitized with each absorbed antiserum. These reagents produced specific coagglutination reactions with suspensions of each Peptostreptococcus reference strain and with 16 clinical isolates. No cross-reactions occurred with the Streptococcus intermedius, Peptococcus magnus, or Peptococcus asaccharolyticus strains tested.

A simple device to reproduce the spatial orientations of the thorax and transducer for serial M-mode and two-dimensional echocardiograms

We have described a device consisting of three circular levels for locating the spatial orientations of the thorax and a transducer that can be used to reproduce the path of the sonic beam through the heart.

M mode and cross-sectional echocardiographic features of flail posterior mitral leaflets

Seventeen patients with accepted M mode echocardiographic criteria for flail mitral leaflet were studied. M mode echocardiograms revealed characteristic disordered mitral valve motion: (1) 16 (94 percent) had chaotic diastolic mitral motion; (2) 14 (82 percent) had systolic mitral flutter; (3) 14 (82 percent) had systolic left atrial echoes; and (4) 12 (71 percent) had systolic mitral valve prolapse. In 8 patients (47 percent) all four findings were present, with three findings present in 16 (35 percent) and two findings present in 13 (18 percent); none had fewer than two findings. Cross-sectional echocardiographic studies in 10 patients revealed a systolic whipping motion of the posterior mitral leaflet into the left atrium in all, abnormal systolic mitral coaptation in all and an abnormal mass of systolic left atrial echoes in 4. None of the first three M mode criteria were observed in 230 patients with uncomplicated "mid systolic click-late systolic murmur" syndrome; cross-sectional echocardiography in 30 of 230 patients revealed normal systolic mitral coaptation and no systolic whipping of the tip of the posterior mitral leaflet into the left atrium.

A simple reliable system for studying antigen-specific murine T cell proliferation

Antigen-specific T cell proliferation can be readily elicited from the popliteal lymph node cells of mice which have received immunizations of antigen in the hind footpads. The advantages of our system over other published methods are (i) simplicity in method and materials, (ii) much improved reproducibility, (iii) negligible concomitant B cell proliferation, (iv) large degrees of antigen specific proliferation with very low background, and (v) complete dependence of the response on accessory cells or macrophages. These results were brought about by proper immunization procedures for mice and judicious choice of culture conditions. Our data show that the system is very suitable for the study of macrophage-T cell interaction in the induction of T cell proliferation as well as the genetic basis of responsiveness or non-responsiveness to protein and polypeptide antigens.

Loss of indicator in the thermodilution technique

The use of a second thermistor for detecting the injectate temperature in the extravascular segment of a standard right heart thermodilution catheter is described. Experiments with chilled (0 degrees C) indicator show that the temperature of the injectate as it enters the catheter is always greater than zero and that it depends on time and the gradient between indicator and surroundings; that serial injections made 30 to 60 seconds apart are successively cooler and do not plateau until the third injection. These variables amount to an overestimation in the cardiac output of 3 to 12%.

Isolation and characterization of muscle membranes using surface-specific labels

Membranes were purified from rat muscle by a differential centrifugation method that avoids the use of salt extraction or incubations at elevated temperature. Three populations of membrane-limited vesicles were defined having average densities of 1.112 (fraction I), 1.141 (fraction II), and 1.158 (fraction III) g/ml in a continuous sucrose gradient. Lactoperoxidase-catalyzed iodination of intact muscle prior to isolation of membranes resulted in highest specific activity in fraction I, although all fractions could be equally labeled after isolation. 125I-Labeled wheat germ agglutinin incubated at low concentration with intact muscle preferentially labeled fraction I. Parallel studies on previously isolated fractions indicated that fraction I also contained the highest concentration of potential receptors for wheat germ agglutinin. In experiments on whole muscle, concanavalin A bound predominantly to sarcolemma with slight variable binding to T-tubular and nuclear membrane but no binding to sarcoplasmic reticulum or mitochondria. Parallel binding studies with isolated membrane fragments indicated heavy binding of concanavalin A by membranes in fraction I with scattered binding in fractions II and III. Na+K+Mg2+ ATPase was specifically enriched in fraction I but was also present in fraction II in a proportion similar to 125I labeling. Ca2+ ATPase was most active in fraction II but present in significant levels in fraction I. It is concluded from these and other data that fraction I contains predominantly sarcolemma membrane, while T-tubular membrane may represent a significant component of fraction II. Ca2+ ATPase activity in fraction I is intrinsic to the sarcolemma.

Cephalexin compared to ampicillin treatment of otitis media

Cephalexin was compared to ampicillin for the treatment of otitis media in a randomized study. Bacteriologic diagnosis was sought by needle tympanocentesis in 179 children. No overall statistically significant differences were noted between the two groups; however, 20 patients who received cephalexin had a poor response to therapy whereas only five recipients of ampicillin responded poorly. A significant difference (P less than .05) between the two regimens was noted when Hemophilus influenzae was recovered. Fifty per cent of the children with H. influenzae otitis media who were treated with cephalexin responded poorly; no patients receiving ampicillin had a poor response. Our data suggest that the use of cephalexin monohydrate is not warranted for treatment of otitis media due to H. influenzae even when the isolate proves sensitive to this drug in vitro. In selected patients with otitis media caused by Staphylococcus aureus which is resistant to penicillin, cephalexin may provide effective treatment.

A model study of facial injury caused by impact while wearing an ophthalmic frame

Damage to facial tissue caused by an ophthalmic frame when there is impact to the face was studied by means of a paraffin-covered mannequin head. Under mild conditions of impact it was easily observed that metal frames and metal components do more tissue damage than is done by a zylframe. A series of the commonly dispensed frames was compared for facial injury potential caused by impact to the face.

Kinetic processes in Escherichia coli membranes and cells. A laser photolysis study using derivatives of pyrene

Pyrene and several derivatives of pyrene are used to investigate photo-induced kinetic processes in whole cells and membranes extracted from Escherichia coli. A mutant of E. coli was used which, under appropriate growth conditions, produced a complete or incomplete lipopolysaccharide in the outer membrane. The pyrene derivatives used were: pyrene sulfonic acid, pyrene butyric acid and the ester of pyrene butyric acid and 10-hydroxydecanoic acid. The pyrene chromophore was excited by the ultraviolet pulse from a Q switch, frequency-doubled, ruby laser. The lifetimes of the pyrene fluorescence in the presence of the quenchers O2, thallous ion (T1+), I-and CH3NO2 were measured and tabulated as second order rate constants. For the most part the quenching rate constants were much lower than the corresponding values observed in simple nonviscous solution, e.g. ethanol. This is interpreted as being due to the location of the probe within the membrane. The membrane inhibits the movement of the quenchers to the excited state. Cell membranes containing complete lipopolysaccharide showed significantly lower quenching rates for the probes pyrene and pyrene sulfonic acid than cell membranes with incomplete lipopolysaccharide. From an amalysis of the kinetic data it is suggested that pyrene and pyrene sulfonic acid are located near and under lipopolysaccharide and close to membrane proteins. On the other hand, no effect of lipopolysaccharide composition was observed for the probes pyrene butyric acid and pyrene butyroyl decanoic acid. This may suggest that these probes are located primarily in the lipid part of the membrane. A simple model for the outer membrane of E. coli is suggested that accounts for the observed laser-induced kinetic processes.

Design for obtaining the half-axial projection

A device for obtaining the half-axial projection complementing single plane cine equipment is described. The design enables a single technician to raise and lower the patient's upper half of the body between 0 degrees and 20 degrees of longitudinal deviation from the rotating cradle, set between 0 degrees and 70 degrees of horizontal deviation. Materials cost less than $100 and can be assembled by personnel in most hospitals.

Aldosterone-Induced Membrane Phospholipid Fatty Acid Metabolism in the Toad Urinary Bladder

Aldosterone action in the isolated toad urinary bladder has been studied by incubation of the tissue with several specifically labeled lipogenic precursors. Within 30 min after hormone addition phospholipid synthesis is stimulated; the metabolism of oleic acid is particularly enhanced. Additionally, during this time interval a phospholipid deacylation-reacylation cycle is stimulated by aldosterone.

Optimizing cinefilm

A system for improving the quality of cinefilm and for maintaining quality control is described. Objective criteria for contrast, resolution, and grain structure were established to measure the effects of varying X-ray dose, f-stop, development temperature, and selection of film and developer. We found that all variables nust be adjusted to maximize the viewing quality and that similar denisty curves can be achieved, independently of the choice of film and developer.

Congenital coronary artery aneurysms

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In vivo sampling of cardiac triglyceride from dogs during ethanol infusion

The feasibility of procuring and analyzing cardiac tissue for triglyceride in vivo was tested in anesthetized dogs. Measurements of triglycerides in samples obtained in vitro confirmed: reproducibility of triplicate analyses of the glycerideglycerol moiety of tissue triglyceride (SEM +/- 2.1%), homogeneity in and between ventricles (SEM +/- 1.8%), and agreement between right endocardial triglyceride and left myocardial triglyceride (difference not significant). Seven dogs received ethanol, 15-30 mg/kg/min, and five dogs received glucose or 0.85% NaCl for 2 hr. Cardiac output and filling pressure were measured from the left ventricle and tissue was taken from the right ventricle with a biopsy catheter before and during infusions. Three to four samples were obtained from each dog; the average weight was 14.4 mg and two to three biopsies were required for each sample. In the ethanol group, triglyceride increased after 15 min and continued to rise; the final triglyceride concentration correlated with the infusion rate. In the glucose-saline group, in vivo triglyceride concentration did not change and did not differ from postmortem triglyceride. Cardiac function declined in the ethanol group and was unaffected in the controls. Thus, multiple in vivo measurements of cardiac lipid are practical and safe and show that ethanol infusions cause early and progressive accumulation of triglyceride in heart muscle.