Acute diffuse phlegmonous esophagogastritis: report of a survived case

A 42-year-old man was admitted because of a persistent pain on swallowing together with epigastralgia, chest pain, fever, and shortness of breath for 5 days. An unbearable shortness of breath with a retrosternal pain was noted each time he tried to lie down. The patient also developed bilateral pleural effusion and pericardial effusion. Ten days after admission, he underwent an emergency laparotomy after an acute episode of severe epigastralgia with hematemesis and rebound tenderness limited to the epigastrium. Operative findings showed diffuse phlegmonous esophagogastritis. A near-total esophagectomy and a total gastrectomy were done. He lost 15 kilograms of body weight and was discharged 3 months later. The patient underwent reconstructive surgery 2 months after discharge, recovered well and regained his weight within one year.

Automated measurement of infarct size with scanned images of triphenyltetrazolium chloride-stained rat brains

BACKGROUND AND PURPOSE

The extent of brain infarction after local cerebral ischemia is frequently assessed with the mitochondrial activity indicator 2,3,5-triphenyltetrazolium chloride (TTC). We describe an automated procedure for analysis of infarct size in TTC-stained rat brains.

METHODS

Rats were subjected to middle cerebral artery occlusion and killed after 24 to 36 hours, and their brains were processed for TTC staining. Digital images of coronal sections from these brains (n > 50) were acquired with a desktop color scanner. The resulting images were divided into red, blue, and green component images. Total brain and infarct areas were automatically determined on the basis of total pixel intensity and area after segmentation of the red and green images, respectively. Automated measurements were compared with those made with a video camera-based image acquisition system that required manual tracing of lesion boundaries.

RESULTS

The spatial resolution of scanned brain images (approximately equal to 200 microns) was comparable to that of the camera-based system and provided sufficient detail to recognize infarct boundaries and neuroanatomical features. Scanner-based acquisition and analysis were faster than with the camera-based method. The green component image accurately distinguished infarcted from normal brain, and the red component image represented total brain dimensions. Infarct measurements obtained by the automated method correlated closely with those from conventional apparatus (R2 = .89, P < .001). Intraobserver reliability with the automated method (R2 = 1.00) was higher than with the conventional method (R2 = .77).

CONCLUSIONS

Infarct size after middle cerebral artery occlusion in the rat can be rapidly and reproducibly assessed with inexpensive scanning equipment and automated image analysis of TTC-stained brains.

MASCIS evaluation of open field locomotor scores: effects of experience and teamwork on reliability. Multicenter Animal Spinal Cord Injury Study

The Multicenter Animal Spinal Cord Injury Study (MASCIS) adopted a modified 21-point open field locomotor scale developed by Basso, Beattie, and Bresnahan (BBB) at Ohio State University (OSU) to measure motor recovery in spinal-injured rats. BBB scores categorize combinations of rat hindlimb movements, trunk position and stability, stepping, coordination, paw placement, toe clearance, and tail position, representing sequential recovery stages that rats attain after spinal cord injury. A total of 22 observers from 8 participating centers assessed 18 hindlimbs of 9 rats at 2-6 weeks after graded spinal cord injury. The observers were segregated into 10 teams. The teams were grouped into 3 cohorts (A, B, and C), consisting of one experienced team from OSU and two non-OSU teams. The cohorts evaluated the rats in three concurrent and sequential sessions. After viewing a rat for 4 min, individual observers first assigned scores without discussion. Members of each team then discussed and assigned a team score. Experience (OSU vs. non-OSU) and teamwork (individual vs. team) had no significant effect on mean scores although the mean scores of one cohort differed significantly from the others (p = 0.0002, ANOVA). However, experience and teamwork significantly influenced reliability of scoring. OSU team scores had a mean standard deviation or discordance of 0.59 points, significantly less than 1.31 points for non-OSU team scores (p = 0.003, ANOVA) and 1.30 points for non-OSU individual scores (p = 0.001, ANOVA). Discordances were greater at the upper and lower ends of the scale, exceeding 2.0 in the lower (< 5) and upper (> 15) ends of the scale but were < 1.0 for scores between 4 and 16. Comparisons of non-OSU and OSU team scores indicated a high reliability coefficient of 0.892 and a correlation index (r2) of 0.894. These results indicate that inexperienced observers can learn quickly to assign consistent BBB scores that approach those given by experienced teams, that the scores are most consistent between 4 and 16, and that experience improves consistency of team scores.

Responses to primary and a booster dose of acellular, component, and whole-cell pertussis vaccines initiated at 2 months of age

A second generation acellular pertussis vaccine (component pertussis vaccine) containing purified pertussis toxin (PT) and filamentous hemagglutinin (FHA) was tested for its immunogenicity and safety in 2-month-old infants in comparison with first-generation acellular and whole-cell pertussis vaccines. At the ages of 2, 4, 6, and 18 months, respectively, 350 subjects were inoculated one dose of pertussis vaccine, which was combined with diphtheria and tetanus toxoids. Both acellular and component vaccines elicited significantly much fewer local and systemic reactions than whole-cell vaccine did. Besides, although not reaching statistical significance, the component vaccine was less reactogenic than the acellular vaccine. After each dose of the primary immunization, antibodies against PT and FHA were much higher in acellular and component pertussis vaccinees than in whole-cell vaccinees. However, at 18 months of age, just before the booster dose, both anti-PT and anti-FHA declined very close to, or even lower than, the prevaccination levels in all three groups and then responded rapidly to a booster dose to attain high levels. The booster responses were also significantly higher (P < 0.01) in acellular and component groups than in whole-cell group. Component and acellular vaccines induced similar levels of anti-FHA but the former induced higher anti-PT than the latter (P < 0.01). Our results indicate that both in primary immunization and as a booster, acellular and component pertussis vaccines are much more immunogenic for PT and FHA and much less reactogenic than whole-cell vaccine. However, the persistence of anti-PT and anti-FHA was not as good as one can expect from other protein antigens without giving a booster dose. A long-term follow-up of the vaccinees has been underway to understand the persistence of these antibodies after the first booster.

Gonadal transformation in male Rana catesbeiana tadpoles intraperitoneally implanted with estradiol capsules

Tadpoles of Rana catesbeiana at TK stages X-XII, about 9 months old, were laparotomized, and the males were implanted intraperitoneally with silastic tubes containing estradiol (E2) for various periods. Male tadpoles implanted with empty tubes served as the controls. Histology, secretions of E2, and testosterone (T) in the gonads were investigated. A rough estimate of estradiol released from silastic tubes suggested that about 90 micrograms per tadpole in 6 months. Histological observation revealed various degrees of transformation from testes toward ovaries in E2-treated testes. Ten in thirteen (77%), the testes were transformed into ovaries 6 months after the treatment. The testes of the controls, however, displayed normal histology. Radioimmunoassay showed that E2 level was increased while T level was decreased in E2-treated testes. These results indicate that a low dose of exogenous E2 may induce transformation of the testes into ovaries.

Malignant soft tissue sarcoma of the hypopharynx successfully treated by radiotherapy alone

Sarcoma of the hypopharynx has been reported very rarely in the literature, only six cases having been found among all head and neck malignancies reported to SEER (Surveillance, Epidemiology, and End Results) during 1973-1987. We report a 14-year-old boy with a huge malignant soft tissue sarcoma arising from the hypopharynx. Tracheostomy and feeding gastrostomy were performed as emergency life-saving procedures. Surgical resection had been attempted, but abandoned. Because of the rapidity of tumor growth, we gave the patient a course of accelerated radiotherapy (170 cGy/fraction, two fractions per day) with a total dose of 7140 cGy within one month. A series of endoscopy and imaging studies demonstrated complete regression of the tumor, and the patient is currently alive without evidence of disease 3.5 years after treatment. We conclude that for an unresectable tumor without distant metastasis, radiation therapy may be tried. The time, dose, and fractionation of radiotherapy should be carefully designed and individualized.

Detection of human T lymphotropic virus type I proviral DNA in patients with diffuse panbronchiolitis

In Japan a number of reported cases of diffuse panbronchiolitis (DPB) have been associated with human T lymphotropic virus type I (HTLV-I) infection. In this study the hypothesis that HTLV-I proviral DNA may be prevalent in DPB was examined using polymerase chain reaction (PCR) for the region of env or the two-step PCR for the pX region of this virus. The presence of HTLV-I proviral DNA was studied in the peripheral blood mononuclear cells (PBMC) obtained from 10 patients with DPB. The presence of proviral DNA in PBMC in 12 patients with chronic obstructive pulmonary disease (COPD), eight patients with idiopathic interstitial pneumonia (IIP), four patients disease were also studied as relevant controls. The lung tissue obtained from 11 patients with DPB, 12 patients with diffuse aspiration bronchiolitis (DAB) at autopsy, and the surgical lung samples obtained from 12 patients with bronchogenic cancer were also studied. Peripheral blood mononuclear cells obtained from one DPB patient and one bronchogenic carcinoma patient were positive for the HTLV-I pX region. The presence of the pX region was also found in the lung tissue of three DPB patients (27.3%) and one DAB patient (8.3%). None of other subjects were positive for HTLV-I proviral DNA, In conclusion, HTLV-I is not the causative virus in the pathogenesis of COPD, IIP, bronchiectasis and bronchogenic carcinoma. There is a likelihood that HTLV-I infection is associated with some cases of DPB; however this association needs further verification.

The role of zinc in selective neuronal death after transient global cerebral ischemia

Zinc is present in presynaptic nerve terminals throughout the mammalian central nervous system and likely serves as an endogenous signaling substance. However, excessive exposure to extracellular zinc can damage central neurons. After transient forebrain ischemia in rats, chelatable zinc accumulated specifically in degenerating neurons in the hippocampal hilus and CA1, as well as in the cerebral cortex, thalamus, striatum, and amygdala. This accumulation preceded neurodegeneration, which could be prevented by the intraventricular injection of a zinc chelating agent. The toxic influx of zinc may be a key mechanism underlying selective neuronal death after transient global ischemic insults.

Adenosquamous carcinoma and schneiderian papilloma-like lesion in a mature cystic teratoma of the ovary: a case report

Malignant transformation is uncommon in the mature cystic teratoma of ovary, in which adenosquamous carcinoma is even rarer. It seldom combines with papillary lesion, like schneiderian papilloma of upper airway. We report such a rare case of mature cystic teratoma undergoing malignant change, with the pictures of both adenosquamous carcinoma and schneiderian papilloma.

High-resolution computed tomography in pulmonary lymphangio(leio)myomatosis and pulmonary tuberous sclerosis

We report two cases where high-resolution computed tomography (HRCT) assisted in the diagnosis of a patient with lymphangioleiomyomatosis and a patient with pulmonary tuberous sclerosis. HRCT was used in both cases where the chest radiographs and conventional computed tomographic scans appeared relatively normal but the conditions were strongly suspected.

Additive neuroprotective effects of dextrorphan and cycloheximide in rats subjected to transient focal cerebral ischemia

Previous studies have implicated both excitotoxicity and apoptosis in the pathogenesis of cerebral infarction induced by focal ischemic insults. Here we tested the possibility that the NMDA antagonist, dextrorphan, and the protein synthesis inhibitor, cycloheximide, would produce additive protective effects in a rodent model of focal ischemia-reperfusion. Transient focal cerebral ischemia was induced by a 90 min period of ligation of the right middle cerebral artery and both common carotid arteries. Administration of either 30 mg/kg dextrorphan or 0.5 mg/kg cycloheximide, given i.p. 15 min before ischemia, reduced infarct volume by about 65%. When optimal concentrations of each drug were given together, infarct volume was reduced by 87% as measured 14 days later. These observations support the idea that both excitotoxicity, and apoptosis dependent on new protein synthesis, contribute to cerebral infarction after transient focal ischemia in the rat.

Dextrorphan reduces infarct volume, vascular injury, and brain edema after ischemic brain injury

Focal cerebral ischemia confined to the cerebral cortex in the right middle cerebral artery (MCA) territory was induced by temporary ligation of the MCA and both common carotid arteries (CCAs). Reperfusion was initiated by releasing all three arterial occlusions after 90 min of ischemia. Infarct volume was morphometrically measured after triphenyltetrazolium chloride staining 24 h postischemia. Blood-brain barrier breakdown was assessed 4 h postischemia by measuring vascular permeability to fluorescein isothiocyanate-conjugated dextran (FITC-D), a macromolecule tracer. Ischemic brain edema was measured based on percent water content, 24 h postischemia. Dextrorphan (DX) 20-10 mg/kg given ip 15 min before ischemia reduced infarct volume in a dose-dependent manner with an apparent U-shaped dose-response curve; best protection was observed at 30 mg/kg. Posttreatment at 30 min, but not 60 min, was still effective. DX (30 mg/kg, given 15 min before ischemia) also reduced the postischemic increase in vascular permeability and brain edema in the right MCA cortex. Results from this study support the idea that NMDA receptor activation contributes to blood-brain barrier breakdown and brain edema after ischemic insults

Very delayed infarction after mild focal cerebral ischemia: a role for apoptosis?

The temporal evolution of cerebral infarction was examined in rats subjected to transient occlusion of both common carotid arteries and the right middle cerebral artery. After severe (90-min) ischemia, substantial right-sided cortical infarction was evident within 6 h and fully developed after 1 day. After mild (30-min) ischemia, no cortical infarction was present after 1 day. However, infarction developed after 3 days; by 2 weeks, infarction volume was as large as that induced by 90-min ischemia. These data suggest that infarction after mild focal ischemia can develop in a surprisingly delayed fashion. Some evidence of neuronal apoptosis was present after severe ischemia, but only to a limited degree. However, 3 days after mild ischemia, neurons bordering the maturing infarction exhibited prominent TUNEL staining, and DNA prepared from the periinfarct area of ischemic cortex showed internucleosomal fragmentation. Furthermore, pretreatment with 1 mg/kg cycloheximide markedly reduced infarction volume 2 weeks after mild ischemia. These data raise the possibility that apoptosis, dependent on active protein synthesis, contributes to the delayed infarction observed in rats subjected to mild transient focal cerebral ischemia.

DNA damage and repair in central nervous system injury: National Institute of Neurological Disorders and Stroke Workshop Summary

BACKGROUND AND PURPOSE

DNA damage and repair are areas of research with important implications for stroke and cerebral trauma. DNA damage is present in central nervous system (CNS) injury, and defects in repair mechanisms are associated with neurodegenerative disease.

METHODS

A workshop, DNA Damage and Repair in CNS Injury, was organized by the National Institute of Neurological Disorders and Stroke in Bethesda, Md, on September 11, 1995. The objective of this workshop was to promote inquiry and to foster application of research in DNA damage and repair after stroke and trauma.

RESULTS

The participants discussed the connection between the fields of DNA damage and repair and stroke and trauma and identified gaps in knowledge to be filled to expand research of DNA damage and repair in CNS injury. Specific recommendations were made targeting research opportunities in the areas of DNA repair and damage in stroke and trauma.

CONCLUSIONS

Research in the science of DNA injury and repair will likely provide new and important information on mechanisms of cell damage and provide opportunities for the development of novel and effective therapies to reduce CNS injury in stroke and trauma.

Cephalosporin and carbacephem nephrotoxicity. Roles of tubular cell uptake and acylating potential

Three beta-lactams, desacetylcephaloglycin, ampicillin, and loracarbef, were studied to test a hypothesis derived from retrospective analysis of previously studied cephalosporins: that beta-lactam nephrotoxicity develops in approximate proportion to tubular cell antibiotic concentrations and lactam ring reactivities. Concentrations of each beta-lactam (and insulin) in rabbit renal cortex and serum were measured at the end of 0.5-hr infusions of 100 mg antibiotic/kg body weight and 0.5 to 0.67 hr later. Total cortical AUCs (total areas under the curve of concentration and time in renal cortex) and transported cortical AUCs (total minus insulin-space beta lactam) were calculated from these measurements. Reactivities, determined by the rate constants of lactam-ring opening at pH 10, were taken from the literature. Nephrotoxicity was quantified by grades of proximal tubular cell necrosis and by serum creatinine concentrations 2 days after infusion of 100-1500 mg/kg of the antibiotics. Desacetylcephaloglycin was slightly less nephrotoxic than cephaloglycin; the AUCs reactivities, and toxicities of these two cephalosporins fit the proposed model, particularly when allowance is made for hepatic and renal deacetylation of cephaloglycin. The very low AUCs, limited reactivity, and absence of nephrotoxicity of ampicillin also fit the model. Loracarbef had a transported AUC less than three times, and reactivity one-thirtieth, those of cefaclor, respectively. Although only at 1500 mg/kg, loracarbef was significantly more nephrotic than cefaclor. If the relativity of loracarbef with its targeted bacterial proteins, which is essentially the same as that of cefaclor, is considered instead of the base hydrolysis rate constant, than loracarbef also fits the model. By the same analysis, the comparatively high in vitro stability of other carbacephems, although pharmaceutically convenient, may not limit their nephrotoxicity.

Antiarrhythmic and electrophysiologic effects of intravenous ibutilide and sotalol in the canine sterile pericarditis model

INTRODUCTION

Atrial arrhythmias are a frequent clinical complication following open heart surgery. We compared the Class III agents d,l-so-talol and ibutilide fumarate in an intravenous cross-over study using the canine atrial sterile pericarditis model.

METHODS AND RESULTS

We studied pacing-induced sustained atrial flutter over a 7-day post-surgical period in conscious dogs, alternating analysis of ibutilide (1.0 to 30.0 micrograms/kg) and d,l-sotalol (0.1 to 3.0 mg/kg). Ibutilide significantly increased atrial flutter cycle length (AFL CL) 11 +/- 2 msec and atrial effective refractory period (AERP) 13 +/- 2 msec, and terminated atrial flutter in all cases (n = 12) following a mean dose of 6 +/- 2 micrograms/kg. Plasma concentrations of ibutilide were 53 +/- 13 ng/mL. Ventricular effective refractory period (VERP) was not significantly affected (4 +/- 2 msec). Following termination with ibutilide, atrial flutter could be reinitiated in 1 of 12 trials, and was nonsustained (40-sec duration). Sotalol significantly increased AFL CL 23 +/- 3 msec and terminated atrial flutter in 8 of 12 trials following a mean dose of 1.5 +/- 0.4 mg/kg. AERP and VERP were significantly increased 20 +/- 6 and 12 +/- 2 msec, respectively. The incidence of reinduced atrial flutter was 9 of 12 trials (P < or = 0.05 vs ibutilide) (7 nonsustained 57 +/- 7 sec duration, and 2 sustained). Sotalol failed to terminate atrial flutter in two dogs on days 1 and 5, despite increases in AFL CL (21 +/- 8 msec) and AERP (16 +/- 9 msec), whereas on day 3, ibutilide (20 +/- 7 micrograms/kg) terminated atrial flutter in those two dogs while increasing AFL CL and AERP 18 +/- 6 and 15 +/- 0 msec, respectively.

CONCLUSION

Both sotalol and ibutilide terminate atrial flutter in this model. Ibutilide converted atrial flutter in dogs in which sotalol was not successful. Following atrial flutter termination, ibutilide had a lower incidence of reinduced arrhythmias compared to sotalol. Ibutilide produced atrial antiarrhythmic effects while having no significant electrophysiologic effects on the ventricle.

Pharmacokinetics of ibutilide and its enantiomers in dogs

Ibutilide fumarate, a new drug for the treatment of cardiac arrhythmias, contains a stereogenic center bearing a secondary alcohol group. Several single dose and multiple dose studies of racemic ibutilide or its enantiomers were performed by the oral and intravenous routes in dogs. A chiral assay was used to examine racemization and the individual enantiomer pharmacokinetics. Following low oral or intravenous doses (approximately 0.3 mg/kg), the pharmacokinetics of the enantiomers were nearly identical, with no substantial chiral conversion. Both enantiomers exhibited high clearance rates, large volumes of distribution, and low oral bioavailability. As the dose increased, pharmacokinetic differences between the enantiomers were observed. The greatest differences (3-fold) were seen after oral administration at 4 mg/kg, indicating that first-pass metabolism of ibutilide was highly enantioselective at high doses. The clearances of the enantiomers differed by up to 34% at 5 mg/kg followed intravenous administration of the racemate. At high doses, other non-linear pharmacokinetic behavior was also apparent. The intravenous clearance of ibutilide declined from 5.3 L/h/kg at 0.3 mg/kg to 3.7 L/h/kg at a dose of 5 mg/kg. The absolute oral bioavailability of the racemate increased from 2% at 0.3 mg/kg to as much as 84% at 5 mg/kg.

Use of recombinant Epstein-Barr virus early antigen for detection of antibody in patients with nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is one of the most common cancers in southern China and Taiwan. Serological studies revealed the close-relationship between NPC and Epstein-Barr virus (EBV). Elevated serum and saliva levels of anti-EBV antibodies are detected in patients with NPC. Therefore, Development Center for Biotechnology prepared the EBV-early antigen (EA-D) by recombinant DNA technique for screening the serum and throat washing samples from patients with head and neck cancers.

METHODS

The BMRF1 gene for EBV early antigen (EA-D) was placed into the plasmid pDB18, then transformed into an Escherichia coli strain containing the lambda cI857 temperature-sensitive repressor. Heat treatment of the transformant, at exponential growth phase, inactivated the cI protein and induced an over-expression of the EA-D protein. Next, the EA-D was purified by chromatography and characterized as a protein of molecular weight 47 kDa, by sodium dodecyl sulfate-polyacry lamide gel electrophoresis (SDS-PAGE) and Western blot analysis using monoclonal anti-EA antibody and sera from patients with nasopharyngeal carcinoma (NPC). Enzyme-linked immunosorbent assay (ELISA) with the purified EA-D antigen was used to screen 129 serum and throat washing (TW) samples from patients with head and neck tumors, 24 from patients with a nonmalignant disease and 44 from normal donors.

RESULTS

Experimental results indicated significantly higher positive rates of EA-D IgA (69%) and EA-D IgG (91%) in NPC sera than in the sera of patients with other head and neck tumors and normal controls. TW samples from patients with NPC also showed a higher positive rate (34%) than the other groups (7-20%).

CONCLUSIONS

Results in this study demonstrate that the bacterially expressed EA-D antigen could be recognized by sera from patients with NPC and monoclonal anti-EA antibody. Thus, it has potential use in ELISA for screening EBV-related diseases such as NPC.

Cytology of metastatic leiomyosarcoma. A case report

BACKGROUND

Metastasis of leiomyosarcoma is not uncommon. Determination of the primary site may be confused with the presenting symptoms and even the known pathology.

CASE

A 62-year-old man presented with chest pain, a productive cough and a lung mass on radiography. Fine needle aspiration of the tumor showed pleomorphic tumor cells. The patient began to have abdominal symptoms one year after presentation. Jejunal leiomyosarcoma was proven after an emergency exploratory laparotomy for mechanical ileus. Sputum cytology disclosed tumor cells one month before death. Necropsy of the lung mass demonstrated findings similar to those of the intestinal tumor microscopically.

CONCLUSION

Without laparotomy, our patient would have been diagnosed as having a primary pulmonary leiomyosarcoma by the presenting symptoms and known pathology.

Neuronal apoptosis: current understanding of molecular mechanisms and potential role in ischemic brain injury

Apoptosis is a rediscovered mechanism of cell death crucial in normal development. Recent exploration of the genetic mechanisms of apoptosis has broadened our insight into the regulation of cell death in development as well as disease states. We present an overview on current understanding of the genetic molecular events in apoptosis in all, or most cell types, with emphasis on events observed in a well-characterized model of neuronal death in vitro. The second part of this article reviews recent studies in in vivo stroke models on the mechanism of cell death relevant to apoptosis after cerebral ischemia. Further delineation of the mechanisms of cell death, especially those that trigger apoptosis, is likely to redirect our approaches in the development of new therapeutic interventions for ischemic stroke.

Inositol trisphosphate, polyphosphoinositide turnover, and high-energy metabolites in focal cerebral ischemia and reperfusion

BACKGROUND AND PURPOSE

Although the signaling pathway involving polyphosphoinositide (poly-PI) hydrolysis and release of inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] is an important mechanism for regulation of neuronal calcium homeostasis, the effect of cerebral ischemia-reperfusion on this calcium signaling pathway is not well understood. Because activity of this pathway is dependent on availability of ATP, this study is aimed at examining the poly-PI signaling pathway and high-energy metabolites in a rat stroke model.

METHODS

Focal cerebral ischemia in rats was induced by temporary occlusion of the right middle cerebral artery and both common carotid arteries. Levels of Ins(1,4,5)P3 were determined by use of the radioreceptor binding assay. Poly-PI turnover in rat cortex was assessed with an in vivo protocol involving intracerebral injection of [3H] inositol and systemic administration of lithium. High-energy metabolites (ATP, ADP, and AMP) were analyzed by high-performance liquid chromatography.

RESULTS

Ischemia induced an increase in poly-PI turnover in the right middle cerebral artery cortex, but reperfusion led to a decline in this signaling activity. However, Ins(1,4,5)P3 levels decreased during ischemia, and these levels were not restored if ischemic insults were longer than 30 minutes. ATP levels decreased to 26% of control during ischemia and recovered to 80% of control during the initial 4 hours of reperfusion; these changes were followed by a second phase of decline.

CONCLUSIONS

Results show an important relationship between ischemia-induced depletion of high-energy metabolites and poly-PI signaling activity. However, the uncoupling between Ins(1,4,5)P3 and ATP during reperfusion after severe ischemia suggests that metabolism of Ins(1,4,5)P3 is more stringently regulated than ATP.