Biomedical subjects

C A Murphy

Publications and source records attributed to C A Murphy.

At least 37 records · Page 2Linked to original sources

PubMed1999

The prognosis of small primary breast cancers.

The Nottingham Prognostic Index (NPI) is an integrated prognostic index used to predict patient survival for women with invasive breast cancer. The index is based on invasive tumour size, histological lymph node stage and tumour grade. The value of such an index has been questioned in small invasive breast cancers and it has been suggested that size is the only necessary prognostic determinant. The aims of this study were to determine the extent of regional lymph node involvement and survival in women with small invasive breast cancers and to assess the value of the NPI. Between 1976 and 1994, 2684 women aged < or = 70 years were treated for primary operable invasive breast cancers of < or = 5 cm in maximum diameter, of which 318 measured < or = 1 cm. Follow-up data were evaluated to determine histological factors important in predicting survival outcomes in women with cancers < or = 1 cm in diameter and comparing their survival according to the NPI with all women treated for primary operable breast cancers < or = 5 cm in maximum diameter. Histological lymph node involvement was demonstrated in 56/318 (18%) of cancers of < or = 1 cm in diameter. Significant survival differences were demonstrated for small breast cancers according to lymph node stage, vascular invasion and histological tumour grade. Only lymph node stage and histological tumour grade were independent prognostic indicators using a multivariate Cox model. The survival curves for small tumours stratified by the NPI were similar to those of cancers up to 5 cm in diameter. The results indicate that lymph node staging and histological grading are still important prognostic determinants for breast cancers < or = 1 cm in diameter. An axillary node staging procedure should be performed for all invasive breast cancers < or = 1 cm in diameter. The NPI remains relevant for small breast cancers.

Adult↗

PubMed1999

Genomic rearrangements in the flagellin genes of Proteus mirabilis.

Molecular analyses have revealed that Proteus mirabilis possesses two genes, flaA and flaB, that are homologous to each other and to flagellin genes of many other species. Both swimmer and swarmer cells transcribe flaA, but not flaB. FlaA- mutants are non-motile and do not differentiate showing the essential role of flaA in swarmer cell differentiation and behaviour. At a low frequency, motile, differentiation-proficient revertants have been found in FlaA-populations. These revertants produce an antigenically and biochemically distinct flagellin protein. The revertant flagellin is the result of a genetic fusion between highly homologous regions of flaA and flaB that places the active flaA promoter and the 5' coding region of flaA adjacent to previously silent regions of flaB generating a hybrid flagellin protein. Analysis of the flaA-flaB region of two such revertants reveals that a portion of this locus has undergone a rearrangement and deletion event that is unique to each revertant. Using a polymerase chain reaction (PCR) to amplify the falA-flaB locus from wild-type swimmer cells, swarmer cells and cells obtained after urinary tract infection, we uncover at least six general classes of rearrangements between flaA and flaB. Each class of rearrangement occurs within one of nine domains of homology between flaA and flaB. Rearrangement of flaA and flaB results in a hybrid flagellin protein of nearly identical size and biochemical properties, suggesting a concerted mechanism may be involved in this process. The data also reveal that the frequency and distribution of flaAB rearrangements is predicted on environmental conditions. Thus, rearrangement between flaA and flaB may be a significant virulence component of P. mirabilis in urinary tract infections.

Amino Acid Sequence↗

PubMed1998

A computer controlled analysis of freezing behaviour.

The conditioned freezing response in rats has been much used both by psychologists and neuroscientists to investigate the behavioural effects of brain lesions and of changes in motivational state. The primary advantage of the freezing response is that it can be used without motivational manipulations such as food or water deprivation. Previously, freezing has been measured by a human observer either from video recordings or during the test sessions themselves. But these methods of data collection have potential disadvantages. In the present paper, we describe a new, computer controlled, automated procedure for assessing conditioned freezing. Each conditioning chamber contains a mini-video camera. Behaviour is analysed on-line by means of a programme which compares every two adjacent seconds of video tape to generate a screen representing the percentage difference between them. A difference of <0.05% (50 pixels) is classified as a freezing response. Experiments are described in which we measure conditioned freezing and its development over time, in response to contextual cues and to a discrete tone which had been paired with foot shock. We demonstrate our apparatus and methods of data analysis to be sensitive to: number of tone-shock pairings, rat strain and tone pre-exposure.

Animals↗

PubMed1998

Odorant-binding proteins of true bugs. Generic specificity, sexual dimorphism, and association with subsets of chemosensory sensilla.

Odorant-binding proteins (OBPs) in insects occur within olfactory sensilla, and are thought to transport chemical stimuli to receptors on dendrites of sensory neurons. Until recently, knowledge of OBPs in insects was limited to moths and Drosophila. We discovered an antennal-specific protein (Lygus [lineolaris] antennal protein, LAP) with a unique N-terminal sequence in the true bug, Lygus lineolaris. We localized LAP to antennae, determined its molecular weight (16 kDa), and showed that while it was expressed in nymphal antennae, its levels dramatically increased in adults concurrent with increases in numbers of olfactory sensilla and electrical responses to odors. In our current study, we used immunological techniques to demonstrate in more detail that LAP occurs only in antennae, and to show its expression within Lygus species. LAP was expressed more in male antennae than in antennae of females for the Lygus species examined. Anti-LAP did not recognize antennal proteins of two other genera of bugs. Immunocytological studies showed LAP primarily within the sensillar lymph of type 1 and type 4 sensilla on antennae. These observations strongly suggest LAP to be an OBP, and our discovery and characterization of OBPs in true bugs provides a third order for use in the study of evolution of OBPs in insects.

Animals↗

PubMed1998

Motoneuron apoptosis is blocked by CEP-1347 (KT 7515), a novel inhibitor of the JNK signaling pathway.

Neurons undergoing apoptosis can be rescued by trophic factors that simultaneously increase the activity of extracellular signal-regulated kinase (ERK) and decrease c-Jun N-terminal kinase (JNK) and p38. We identified a molecule, CEP-1347 (KT7515), that rescues motoneurons undergoing apoptosis and investigated its effect on ERK1 and JNK1 activity. Cultured rat embryonic motoneurons, in the absence of trophic factor, began to die 24-48 hr after plating. During the first 24 hr ERK1 activity was unchanged, whereas JNK1 activity increased fourfold. CEP-1347 completely rescued motoneurons for at least 72 hr with an EC50 of 20 +/- 2 nM. CEP-1347 did not alter ERK1 activity but rapidly inhibited JNK1 activation. The IC50 of CEP-1347 for JNK1 activation was the same as the EC50 for motoneuron survival. Inhibition of JNK1 activation by CEP-1347 was not selective to motoneurons. CEP-1347 also inhibited JNK1 activity in Cos7 cells under conditions of ultraviolet irradiation, osmotic shock, and inhibition of glycosylation. Inhibition by CEP-1347 of the JNK1 signaling pathway appeared to be selective, because CEP-1347 did not inhibit p38-regulated mitogen-activated protein kinase-activated protein kinase-2 (MAPKAP2) activity in Cos7 cells subjected to osmotic shock. The direct molecular target of CEP-1347 was not JNK1, because CEP-1347 did not inhibit JNK1 activity in Cos7 cells cotransfected with MEKK1 and JNK1 cDNA constructs. This is the first demonstration of a small organic molecule that promotes motoneuron survival and that simultaneously inhibits the JNK1 signaling cascade.

Animals↗

PubMed1998

Intergeneric distribution and immunolocalization of a putative odorant-binding protein in true bugs (Hemiptera, Heteroptera).

Lygus antennal protein (LAP) is an olfactory-related protein of the tarnished plant bug Lygus lineolaris (Hemiptera, Heteroptera: Miridae), a hemimetabolous insect. In previous work, a polyclonal antiserum was generated against the N-terminal sequence of LAP; LAP immunoreactivity was strongest in antennae of adult males, but was also present in antennae of adult females and of nymphs. In the current study, LAP immunoreactivity was examined to determine the species specificity and the tissue and cellular localization of LAP expression. Western blot analysis indicated that LAP immunoreactivity was present in the antennae of the male congeners L. lineolaris and L. hesperous, but was not detectable in male antennae of the more distant relatives Podisus maculiventris or Nezara viridula (Hemiptera, Heteroptera: Pentatomidae). Western blot analysis further confirmed that LAP expression was restricted to antennal tissue. Histological analyses showed that LAP expression within the antennae was specifically associated with chemosensory sensilla on the antenna. Within the sensilla, LAP immunoreactivity was distributed throughout the extracellular lumen and was concentrated in dense granules within the cytoplasm of sensillar support cells. LAP immunoreactivity was restricted to a subset of antennal chemosensory sensilla, specifically the multiporous olfactory sensilla. These findings suggest that LAP has an important olfactory function in Lygus sp., possibly related to that of odorant-binding proteins (OBP) found in other insect orders. If so, LAP would be the first OBP-like protein characterized outside the Endopterygota.

Animals↗

PubMed1997

Selective aortic arch perfusion during cardiac arrest: enhanced resuscitation using oxygenated perflubron emulsion, with and without aortic arch epinephrine.

STUDY OBJECTIVE: To evaluate selective aortic arch perfusion (SAAP) with an oxygenated fluorocarbon emulsion, with and without aortic arch epinephrine during cardiac arrest. METHODS: This randomized, controlled study, undertaken at a university research laboratory, involved 15 mixed-breed dogs. After 10 minutes of ventricular fibrillation and 30 seconds of CPR, the dogs were randomized to three groups, each comprising five dogs. Group 1 (controls) dogs were given CPR and intravenous epinephrine, .01 mg/kg, at 10.5 minutes and then every 3 minutes. Group 2 dogs (IVE-SAAP) were treated with CPR and intravenous epinephrine (IVE) in the same fashion as the control group but were also subjected to SAAP with 275 mL of oxygenated 60% wt/vol perflubron emulsion over 30 seconds. Group 3 dogs (AoE-SAAP) received the same treatment as the IVE-SAAP group, except that the first epinephrine dose was given intraaortically. RESULTS: Coronary perfusion pressure (CPP) increased during SAAP in both the IVE-SAAP and AoE-SAAP groups but was greater in the AoE-SAAP group. CPR diastolic CPP after SAAP was significantly greater in the AoE-SAAP group than in the control group. Return of spontaneous circulation (ROSC) occurred in two control dogs, all five IVE-SAAP dogs, and all five AoE-SAAP dogs. The time elapsed from the initiation of CPR to ROSC was 6.1 +/- 1.9 minutes in the AoE-SAAP group, compared with 11.0 +/- 5.8 minutes in the IVE-SAAP group. CONCLUSION: SAAP with oxygenated perflubron emulsion improved ROSC, both with and without aortic arch epinephrine. The combination of SAAP with perflubron emulsion and aortic arch epinephrine resulted in higher CPP and more rapid ROSC.

Animals↗

PubMed1997

Selective aortic arch perfusion using serial infusions of perflubron emulsion.

OBJECTIVE: To determine whether selective aortic arch perfusion (SAAP) using serial infusions of oxygenated perflubron emulsion combined with aortic epinephrine (AoE) administration is more effective than conventional therapy in treating cardiac arrest. METHODS: An experimental cardiac arrest model (10 min ventricular fibrillation and 2 min CPR) was used with 12 mixed-breed canines, randomized into 2 groups: control (n = 6), CPR and IV epinephrine, 0.01 mg/kg, at 12 min and then every 3 min; or AoE-SAAP (n = 6), CPR and aortic epinephrine, 0.01 mg/kg, at 12 min and then every 3 min, and serial SAAP with oxygenated 60% weight/volume (w/v) perflubron emulsion as follows: 300 mL over 30 sec at 12 min as continuous SAAP without CPR; 150 mL over 20-30 sec at 15 min and 18 min as pulsed diastolic SAAP during CPR. RESULTS: AoE-SAAP resulted in increased coronary perfusion pressure (CPP) and return of spontaneous circulation (ROSC) compared with control. CPR-diastolic (release phase) CPP during pulsed diastolic SAAP was similar to or greater in magnitude than the CPP generated during the initial SAAP infusion without CPR. ROSC for control was 0/6 and for AoE-SAAP was 4/6 (p < 0.05, Fisher's exact test). Time from initiation of CPR to ROSC with a sustained systolic aortic pressure > 60 mm Hg was 8.0 +/- 1.2 min in the 4 resuscitated AoE-SAAP animals. CONCLUSION: The combination of AoE with SAAP infusions of oxygenated perflubron emulsion was more effective than conventional resuscitation therapy. Pulsed diastolic SAAP is a promising method for performing SAAP.

Analysis of Variance↗

PubMed1997

Imaging thin and thick sections of biological tissue with the secondary electron detector in a field-emission scanning electron microscope.

A field-emission scanning electron microscope (FESEM) equipped with the standard secondary electron (SE) detector was used to image thin (70-90 nm) and thick (1-3 microns) sections of biological materials that were chemically fixed, dehydrated, and embedded in resin. The preparation procedures, as well as subsequent staining of the sections, were identical to those commonly used to prepare thin sections of biological material for observation with the transmission electron microscope (TEM). The results suggested that the heavy metals, namely, osmium, uranium, and lead, that were used for postfixation and staining of the tissue provided an adequate SE signal that enabled imaging of the cells and organelles present in the sections. The FESEM was also used to image sections of tissues that were selectively stained using cytochemical and immunocytochemical techniques. Furthermore, thick sections could also be imaged in the SE mode. Stereo pairs of thick sections were easily recorded and provided images that approached those normally associated with high-voltage TEM.

Animals↗

PubMed1996

Laparoscopic common bile duct exploration: evolution of a new technique.

Laparoscopic exploration of the common bile duct (CBD) with a choledochoscope or a stone basket during laparoscopic cholecystectomy was attempted in 60 patients and was successful in 56. The cystic duct was used for entry to the CBD in 46 patients and in 14 a choledochotomy was performed. Of 51 patients with confirmed common duct stones, 38 had complete laparoscopic clearance (75 per cent). In 13 patients the duct was not cleared or was only partially cleared, of whom four went on to have clearance by postoperative percutaneous choledochoscopy down a cystic duct or T-tube track. Two patients with cystic duct tubes passed their remaining stones spontaneously. One patient had open exploration and six required endoscopic retrograde cholangiopancreatography. Of nine patients without stones, choledochoscopy was impossible in three patients whose cholangiogram was later considered to be normal. In five patients stones were excluded by choledochoscopy and in one patient laparoscopic choledochoscopy was undertaken to better define abnormal biliary anatomy; this helped to avoid major bile duct injury. Choledochoscopy was easier with the smaller 3.6-mm ureteroscope but stone removal was more difficult when the basket was too small for the stones, the cystic duct too small relative to stone size or the number of stones was too great. Successful stone clearance was proportional to the level of effort expended, and was limited by operating time and equipment.

Cholangiography↗

PubMed1996

Lesion of the habenular efferent pathway produces anxiety and locomotor hyperactivity in rats: a comparison of the effects of neonatal and adult lesions.

Recent studies have implicated the habenula in modulating states of arousal and chronic responses to stress. We examined whether lesion of the habenula efferent pathway, the fasciculus retroflexus (FR), at either 3 (P3) or 70 (P70) days of age affects stress-related anxiety (elevated plus-maze test) and activity levels (open-field test) in rats tested as adults. Both P3- and P70-lesioned rats showed chronically elevated plasma levels of corticosterone. Rats receiving FR lesions as neonates (P3) exhibited greater open arm avoidance on the elevated plus-maze than controls 2 months postoperatively, suggesting a heightened state of anxiety. In contrast, P70-lesioned rats behaved similarly to controls on the plus-maze, but showed increased locomotion and increased grooming in the open field, effects not observed in P3-lesioned rats. When an additional stressful condition was imposed (5 days of social isolation plus 24 h food deprivation) before testing, both FR-lesion groups showed an attenuation of the normal behavioral responses (decreased open-arm entries/time in open arms, increased freezing). The effects of FR lesions on activity and behavioral indices of anxiety may be due to disruption of lateral habenular projections to dopaminergic neurons in the ventral tegmentum and/or projections to regions containing high concentrations of benzodiazepine receptors, the median and dorsal raphe and dorsal periaqueductal gray. Behavioral differences observed as a function of lesion age suggest differential capabilities of P3- and P70-lesioned rats to utilize compensatory mechanisms to correct FR lesion-induced deficits.

Aging↗

PubMed1996

County wide employment and population growth: an analysis of the 1980s.

"Regional scientists remain interested in studying interregional differences in the growth rates of population and employment. Following the earlier work of Carlino and Mills, this paper examines growth trends at the county level in the U.S. during the period 1981-1989. Five major sectors of employment are examined. A partial adjustment model is developed that captures intercounty differences in amenities, business and fiscal conditions, demography, employment structure, and relative location. Some evidence is given that population and employment growth was simultaneous, although feedback effects apparently were not strong."

Americas↗

PubMed1996

Fusarium polycaprolactone depolymerase is cutinase.

Polycaprolactone (PCL), a synthetic polyester, is degraded by a variety of microorganisms, including some phytopathogens. Many phytopathogens secrete cutinase, a serine hydrolase that degrades cutin, the structural polymer of the plant cuticle. We compared wild-type strains and a cutinase-negative gene replacement mutant strain of Fusarium solani f. sp. pisi (D. J. Stahl and W. Schäfer, Plant Cell 4:621-629, 1992) and a wild-type strain of Fusarium moniliforme to show that Fusarium cutinase is a PCL depolymerase. The wild-type strains, but not the mutant strain, (i) degraded PCL and used it as a source of carbon and energy, (ii) showed induction of secreted PCL depolymerase and an esterase activity of cutinase when grown in the presence of cutin, and (iii) showed induction of PCL depolymerase and an esterase activity of cutinase when grown in the presence of a hydrolysate of PCL, which contains PCL oligomers that are structurally similar to the natural inducers of cutinase. These results together with other details of regulation and conditions for optimal enzyme activity indicate that the Fusarium PCL depolymerase, required for degradation and utilization of PCL, is cutinase.

Biodegradation, Environmental↗

PubMed1996

Strain-dependent variation in the NADH-dependent diacetyl reductase activities of larger- and alebrewing yeasts.

Significant differences were observed in the zymogram patterns of NAD(+)-dependent ethanol dehydrogenase and acetoin dehydrogenase activity in seven strains of brewer's yeast examined by non-denaturing PAGE. Bottom-fermenting (lager) strains contained quite different activity bands of acetoin dehydrogenase activity compared with top-fermenting (ale) strains. These differences were confirmed when cell-free extracts of ale yeasts were heated at 55 degrees C. This destroyed most of the diacetyl reductase activity, while leaving acetaldehyde reductase and other reductase activities unaffected. In contrast, heating cell-free extracts of lager yeasts at 55 degrees C inactivated diacetyl reductase activity and the other reductase activities at the same rate, and more slowly than with ale strains. Similar distinctions between the two types of yeast could be made by examining the effect of heat on the ratio (activity of the various substrates with NADH as electron donor)/(activity with reduced acetylpyridine-adenine dinucleotide as electron donor). The data show that the acetoin dehydrogenase/diacetyl reductase enzyme present in ale-yeast strains differs in mobility and heat-stability from that of larger strains, and that both can be distinguished from the major alcohol dehydrogenase activity bands.

Acetoin Dehydrogenase↗

PubMed1995

Baroreflex control of heart rate in Dahl hypertensive (SS/Jr) and normotensive (SR/Jr) rats.

OBJECTIVE: To determine whether impaired reflex control of heart rate was evident in rats of the inbred Dahl hypertension-sensitive (SS/Jr) strains. DESIGN AND METHODS: Phenylephrine and sodium nitroprusside were administered through jugular catheters in graded doses to elicit a range of pressor and depressor responses, for which corresponding reflex decreases and increases in heart rate were recorded. To assess the relative contributions of sympathetic and parasympathetic branches of autonomic control to baroreflex functioning, atropine methyl nitrate and atenolol were administered to establish vagal blockade, and cardiac sympathetic blockade, respectively. RESULTS: Assuming a sigmoidal relationship between mean arterial pressure and heart rate changes, our results indicated that SS/Jr rats exhibited elevated blood pressure set-points for baroreceptor activation and roughly similar baroreflex sensitivity compared with SR/Jr rats. In contrast, using linear regression analyses, our results indicated that SS/Jr rats had significant reductions in baroreceptor sensitivity when arterial pressure was increased by phenylephrine. Baroreceptor sensitivity was similar between rats of the two strains when arterial pressure was reduced by administration of nitroprusside. Atropine and atenolol had similar effects on baroreflex control of heart rate in both strains. However, pressor responses to phenylephrine were significantly greater in SS/Jr rats, an effect which had previously been reported in Dahl salt-sensitive (DS) rats and attributed to deficits in autonomic reflex control of vascular resistance. CONCLUSION: The present results indicate that the method of analysis for determination of baroreceptor sensitivity can influence the conclusions drawn in studies of hypertensive and normotensive strains of rat. Although deficits in baroreflex control of heart rate have consistently been reported in DS rats, the present results did not confirm those findings in inbred Dahl rats when mean arterial pressure and heart rate change data were analyzed by fitting a logistic equation to sigmoid data. In contrast, using linear regression analysis, those same data did reveal a defect in baroreceptor sensitivity of SS/Jr rats after acute increases in arterial pressure. Caution should be exercised in the selection of a method for analysis of baroreceptor data and the interpretation of the findings.

Animals↗

PubMed1994

Studies of the mechanism underlying increased Na+/Ca2+ exchange activity in Alzheimer's disease brain.

The Na+/Ca2+ exchanger was characterized in plasma membrane vesicles derived from frozen human postmortem tissues. The frontal cortex, temporal cortex and cerebellum of control and Alzheimer's disease (AD) tissues were compared. Na+/Ca2+ exchange activity was defined as the change in vesicular Ca2+ content seen after Na+ loaded vesicles were diluted into choline buffer. The time course of changes in Ca2+ content after dilution was similar in all three regions of control brain. In AD brain, both frontal and temporal cortex vesicles showed elevated Ca2+ content, most evident as an increased peak Ca2+ content at 2 min. The AD cerebellar cortex time course was similar to control and did not show an elevated peak at 2 min. No differences were seen in the passive permeability to Ca2+ when comparing plasma membrane vesicles prepared from control and AD brain. Vesicles from the frontal and temporal cortex of AD brain showed increases in the Vmax of the initial velocity of Ca2+ uptake when compared to control brain, whereas, the cerebellum did not. There were no significant effects of AD on the Km for Ca2+ activation of the initial velocity. Ca2+ influx measured during the rise in vesicular Ca2+ content was elevated in vesicles from AD temporal cortex when compared to control. Two known inhibitors (exchange inhibitory peptide and dichlorobenzamil) of the cardiac Na+/Ca2+ exchanger inhibited the human brain exchanger equally well in control and AD vesicles. Increased Na+/Ca2+ exchange activity was not due to astrocytic gliosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Alzheimer Disease↗

PubMed1994

A molecular phylogeny of the marine red algae (Rhodophyta) based on the nuclear small-subunit rRNA gene.

A phylogeny of marine Rhodophyta has been inferred by a number of methods from nucleotide sequences of nuclear genes encoding small subunit rRNA from 39 species in 15 orders. Sequence divergences are relatively large, especially among bangiophytes and even among congeners in this group. Subclass Bangiophycidae appears polyphyletic, encompassing at least three lineages, with Porphyridiales distributed between two of these. Subclass Florideophycidae is monophyletic, with Hildenbrandiales, Corallinales, Ahnfeltiales, and a close association of Nemaliales, Acrochaetiales, and Palmariales forming the four deepest branches. Cermiales may represent a convergence of vegetative and reproductive morphologies, as family Ceramiaceae is at best weakly related to the rest of the order, and one of its members appears to be allied to Gelidiales. Except for Gigartinales, for which more data are required, the other florideophyte orders appear distinct and taxonomically justified. A good correlation was observed with taxonomy based on pit-plug ultrastructure. Tests under maximum-likelihood and parsimony of alternative phylogenies based on structure and chemistry refuted suggestions that Acrochaetiales is the most primitive florideophyte order and that Gelidiales and Hildenbrandiales are sister groups.

Base Sequence↗

PubMed1993

Aortic arch versus central venous epinephrine during CPR.

STUDY OBJECTIVE: To determine if delivery of epinephrine to the peripheral arterial system by an aortic arch catheter is more effective than central venous epinephrine administration during cardiac resuscitation. DESIGN: Randomized, nonblinded, controlled trial. TYPE OF PARTICIPANTS: Sixteen mongrel canines (25 to 31 kg). INTERVENTIONS: Animals had aortic arch pressure, and right atrial pressure, superior vena cava infusion, and descending aortic arch infusion catheters placed using fluoroscopy. After ten minutes of ventricular fibrillation, three DC countershocks were delivered over one minute. If unsuccessful, CPR at 120 compressions per minute was begun, and at 60 seconds of CPR, epinephrine (1 mg/50 mL normal saline) was administered either through the superior vena cava or the aortic arch catheter followed by one more minute of CPR. Defibrillation then was attempted and, if unsuccessful, further resuscitative efforts followed advanced cardiac life support guidelines, except route and dose of epinephrine remained the same. MEASUREMENTS AND MAIN RESULTS: Aortic arch pressure, right atrial pressure, and coronary perfusion pressure (diastolic aortic arch pressure minus diastolic right atrial pressure) were recorded continuously. Aortic arch pressure and coronary perfusion pressure increased more rapidly and to a greater magnitude with aortic arch-epinephrine than superior vena cava-epinephrine. Coronary perfusion pressure doubled by ten seconds in seven of eight in the aortic arch-epinephrine group versus none in the superior vena cava-epinephrine group. Aortic arch pressure and coronary perfusion pressure increases consistently plateaued within 60 seconds after aortic arch-epinephrine but not after superior vena cava-epinephrine. Return of spontaneous circulation was faster (P < .05) in the aortic arch-epinephrine group. Maximal coronary perfusion pressure after epinephrine correlated with the coronary perfusion pressure immediately before epinephrine administration in both groups, but more strongly in the aortic arch-epinephrine group (P = .0001). CONCLUSION: For an equivalent dose of epinephrine, aortic arch administration produces a more rapid response and more rapid peak effect than central venous administration. The combination of aortic arch-epinephrine administration and aortic pressure monitoring may be useful when initial standard resuscitative measures have not been successful.

Animals↗