The persistence of drug-induced fever by teicoplanin--a case report.

OBJECTIVE: It was reported that the drug-induced fever of teicoplanin tended to persist after cessation of treatment. It is considered that the long half-life of teicoplanin causes the phenomenon. However there was no detailed report regarding plasma concentration of teicoplanin during onset of drug induced-fever. Therefore we investigated the relation between persistence of drug-induced fever and plasma concentration of teicoplanin. CASE: A 38-year-old male patient on the Left Ventricular Assist System (LVAS) was treated with teicoplanin for methicillin-resistant Staphylococcus aureus (MRSA) and he experienced drug-induced fever. Plasma concentrations of teicoplanin were measured not only during the treatment with the drug but also after it was discontinued. As such, plasma concentration was measured even when the fever had subsided. RESULTS: On Day 9 of treatment, the dose was increased from 400 to 600 mg, but the patient had a fever of about 38 - 39 °C. When the treatment was discontinued, it took 9 days for the fever to subside to a temperature of about 37 °C. The half-life of elimination of teicoplanin in the elimination phase is about 108 h, which is long. The fever persisted until the plasma concentration decreased to below 10 µg/ml, which is the effective trough concentration, and subsided when the estimated blood concentration was 7.5 µg/ml. CONCLUSIONS: We suggest that there is the possibility that the drug-induced fever due to teicoplanin persisted until the plasma concentration had decreased adequately. Close monitoring of plasma concentration is necessary, particularly when teicoplanin clearance is decreased such as in patients with renal dysfunction.

Influence of IOP measurement through the wrong eyepiece of the slit lamp on Goldmann applanation tonometry.

PURPOSE: This study examined whether intraocular pressure (IOP) measurements through the wrong eyepiece of the slit lamp may be a source of error. METHODS: Seven skilled observers measured the IOP from seven healthy subjects. The observers used a Haag-Streit Goldmann applanation tonometer with two types of slit lamps (Haag-Streit and Rodenstock). In the Haag-Streit slit lamp the prism of the tonometer is aligned with the right part of the slit lamp optics. Conversely, in the Rodenstock slit lamp, the prism is aligned with the left. Each observer measured the IOP of each subject through the right eyepiece, through the left eyepiece, and under binocular vision. RESULTS: The IOP measured with the left eyepiece of the Haag-Streit slit lamp was significantly higher than that measured with the right eyepiece and binocular vision. The IOP measured with the right eyepiece of the Rodenstock slit lamp was significantly higher than that measured with the left eyepiece and binocular vision. CONCLUSIONS: IOP measurement through the wrong eyepiece of the slit lamp may be a source of error.

Clinical Outcomes of Patients With the HeartMate II Left Ventricular Assist Device: A Single-center Experience From Japan.

BACKGROUND: Left ventricular assist device (LVAD) therapy is the "gold standard" alternative therapy for patients with advanced heart failure. However, LVAD therapy is still uncommon in the Asia-Pacific region. Therefore, we aimed to elucidate the clinical outcomes of patients from Japan supported with the HeartMate II (HM-II) LVAD at our institution. METHODS: Ninety-two patients (mean 44.3 ± 12.1 years, 68 men, average body mass index 1.65 ± 0.28 m2; 81 with nonischemic cardiomyopathy) who underwent HM-II implantation for bridge to transplantation (n = 91) or for destination therapy in a clinical study (n = 1) at the National Cerebral and Cardiovascular Center between April 2013 and October 2017 were enrolled in this analysis. Preoperatively, most patients (n = 73, 79%) had an INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) profile of between level 2 and 4. Postoperatively, the average pump speed was 8602 ± 258 rpm and the hemodynamics were well compensated. RESULTS: Adverse events consisted of 38 (41.3%) hemolysis, 30 (32.6%) major infection, 27 (29.3%) major bleeding (6 [6.5%] with gastrointestinal bleeding), and 18 (19.6%) neurologic dysfunction events. Eighteen patients underwent heart transplantation (HTx) after an average of 32.9 ± 8.9 months of VAD support, and overall survival at both 6 months and 3 years was 96.3%. CONCLUSION: Clinical outcome among patients with HM-II at our institution is satisfactory for both survival and adverse events. The HM-II can provide effective hemodynamic support during the extremely long waiting period for HTx in Japan.

Paradoxical Reaction of Tuberculosis in a Heart Transplant Recipient During Antituberculosis Therapy: A Case Report.

INTRODUCTION: Tuberculous paradoxical reactions (PRs) are excessive immune reactions occurring after antituberculosis (TB) treatment and are commonly observed in immunocompromised hosts such as patients infected with the human immunodeficiency virus. CASE REPORT: We recently encountered a 63-year-old male heart transplant recipient who developed tuberculous PR after treatment for miliary TB. The patient had been receiving immunosuppressive therapy with cyclosporine and mycophenolate mofetil for over 15 years. The diagnosis of miliary TB was made based on the presence of intermittent fever and fatigue; thus, anti-TB treatments (isoniazid, levofloxacin, ethambutol, and pyrazinamide) were started, which led to rapid defervescence and regression of the granular shadow and pleural effusion. However, a new persistent fever and confused state developed 1 month after the anti-TB therapy was started. After excluding possible etiologies of the patient's symptom, a PR was suspected, and anti-TB drugs were continued; corticosteroids were added as anti-inflammatory agents. After that, he has shown a favorable course with long-term anti-TB chemotherapy. CONCLUSION: A PR should always be considered when the patients' symptoms of tuberculosis re-exacerbate after an appropriate anti-TB therapy. A PR commonly occurs in patients with various immunologic conditions including heart transplant recipients.

Terminal Ileac Ulcers Mimicked Post-transplantation Lymphoproliferative Disorder in a Heart Recipient Treated With Everolimus: A Case Report.

Post-transplant lymphoproliferative disorder (PTLD) is a well-recognized and potentially fatal complication of cardiac transplantation that commonly involves the gastrointestinal tract. Herein, we report a case of life-threatening gastrointestinal bleeding from recurrent terminal ileac ulcers mimicking PTLD in a heart recipient treated with everolimus (EVL). A 40-year-old man underwent heart transplantation for dilated cardiomyopathy 3 years prior to the current admission and was treated with tacrolimus and EVL. He was admitted to a local hospital because of fever, abdominal pain, and diarrhea. His symptoms persisted and, 3 weeks later, hematochezia occurred; thus, he was transferred to our hospital. As computed tomography and 18F-fluorodeoxyglucose positron emission tomography showed bowel-wall thickening of the terminal ileum, gastrointestinal PTLD was initially suspected. However, although colonoscopy- performed after switching EVL to mycophenolate mofetil (MMF)-showed terminal ileac ulcers, the histologic examination revealed no findings corresponding to PTLD. As EVL may delay ulcer healing, MMF was maintained for 3 months. After repeated colonoscopy showed ulcer healing, MMF was switched back to EVL for cardiac allograft vasculopathy prevention. Three weeks later, he was emergently admitted to a local hospital for life-threatening gastrointestinal bleeding from a recurrent terminal ileal ulcer, which required hemostatic forceps hemostasis. As EVL is suspected to be associated with recurrent ileal ulcers, EVL was again switched back to MMF. The ileal ulcers resolved, without recurrence in 3 months of clinical follow-up. This case demonstrates that cases of life-threatening gastrointestinal bleeding from recurrent terminal ileac ulcers can mimic PTLD in a heart recipient treated with EVL.

Percutaneous Coronary Intervention and Coronary Artery Bypass Grafting in Heart Transplant Recipients With Transplant Coronary Arterial Vasculopathy.

BACKGROUND: Transplant coronary arterial vasculopathy (TCAV) is a major cause of death after heart transplantation (HTx). Palliative coronary revascularization has been attempted in patients with severe TCAV; however, the outcome has not been fully elucidated. METHODS: Ninety-six patients who were treated after HTx at our institute between 1999 and 2015 were screened for TCAV. TCAV was defined as >70% stenosis on coronary angiography (CAG) or a maximal intimal thickness of >0.5 mm in the right or left coronary arteries on intracoronary ultrasonography (IVUS). In the present study, the outcomes of patients with severe TCAV who underwent percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) were investigated. RESULTS: TCAV containing donor-transmitted atherosclerosis was cumulatively found in 69 patients (71.9% of the total; mean age, 34.6 ± 13.1 years; 52 men; mean follow-up duration, 83.0 ± 60.4 months). Five (7.2%) and 64 (92.8%) of the 69 patients were diagnosed as having TCAV by use of CAG and IVUS, respectively. All 5 patients diagnosed by with the use of CAG underwent coronary revascularization between 1 and 236 months after HTx. Three patients underwent PCI with drug-eluting stents, with a primary success rate of 100%. No angiographic restenosis occurred in 2 patients at 31 and 36 months after PCI, respectively. Meanwhile, 2 patients underwent CABG. No peri-operative complications occurred, and all grafts were patent as assessed by use of CAG at 34 and 5 months after CABG. CONCLUSIONS: Coronary revascularization was feasible and effective for severe TCAV with middle-term follow-up.

Reversible Cerebral Vasoconstriction Syndrome After Heart Transplantation: A Case Report.

BACKGROUND: Reversible cerebral vasoconstriction syndrome (RCVS) is a transient cerebrovascular disorder putatively caused by some immunosuppressive agents. CASE REPORT: We recently encountered a 47-year-old female patient diagnosed with dilated cardiomyopathy who developed RCVS after heart transplantation. A triple-drug regimen consisting of tacrolimus, mycophenolate mofetil, and a corticosteroid was started after surgery. On postoperative day (POD) 11, the patient developed a severe headache, although computed tomography of the head demonstrated no signs of hemorrhage or infarction. At first, both a painkiller and migraine drugs were regularly administered to the patient. On POD 21, however, she developed an unbearable headache with a visual field defect and mild hemiparesis of the right hand. Magnetic resonance imaging (MRI) of the brain revealed a cerebral infarction in the left occipital lobe with diffuse vasoconstriction of both the middle and posterior cerebral arteries. A diagnosis of RCVS was made and tacrolimus, a drug suspected to cause RCVS, was discontinued. In its place, two doses of basiliximab followed by everolimus, both of which are alternatives for tacrolimus, were given. The corticosteroid dose was also increased. Furthermore, to release vasoconstriction, both verapamil and diltiazem were administered. On POD 27, cerebrovascular constrictions were shown to be relieved on brain MRI and the patient's neurological symptoms subsequently almost completely diminished. CONCLUSION: RCVS should always be considered as a cause of headache in heart transplant recipients because tacrolimus, an immunosuppressive agent, may trigger RCVS. This will allow rapid intervention that is essential for avoiding irreversible neurological deficits.

Decreased Na+-gradient-dependent D-glucose transport in brush-border membrane vesicles from rabbits with experimental Fanconi syndrome.

The effect of anhydro-4-epitetracycline on sodium gradient-dependent D-glucose transport of rabbit renal brush-border membrane vesicles was studied. The purity of isolated brush-border membrane vesicles as judged by enzyme activities was not different between normal control and anhydro-4-epitetracycline-administered rabbits. There was no difference in estimate of intravesicular volume, either. When NaCl was used for sodium gradient, the overshoot of D-glucose uptake into brush-border membrane vesicles isolated from anhydro-4-epitetracycline-treated rabbits was significantly smaller than that of normal control rabbits. In the cases of NaSCN or Na2SO4, the former was also smaller than the latter, but not significantly so. To avoid the possible effect of membrane potential on D-glucose uptake, the voltage-clamp method was applied. Even in the voltage-clamped condition, the overshoot of D-glucose uptake into vesicles from anhydro-4-epitetracycline-treated rabbits was decreased compared to that of normal rabbits. In vitro incubation of brush-border membrane vesicles with 20 mM anhydro-4-epitetracycline caused no alteration in sodium gradient-dependent D-glucose uptake. Our results demonstrate that there exists a disorder in sodium gradient-dependent D-glucose uptake of renal brush-border membrane in anhydro-4-epitetracycline-treated rabbits, and suggest that this disorder is one of the underlying mechanisms of experimental Fanconi syndrome.

The mechanism of decreased Na+-dependent D-glucose transport in brush-border membrane vesicles from rabbit kidneys with experimental Fanconi syndrome.

In our previous paper (Yanase, M. et al. (1983) Biochim. Biophys. Acta 733, 95-101) we reported that the Na+-dependent D-glucose uptake into brush-border membrane vesicles is decreased in rabbits with experimental Fanconi syndrome (induced by anhydro-4-epitetracycline). In the present paper we investigate the mechanism underlying this decrease. D-Glucose is taken up into the osmotically active space in anhydro-4-epitetracycline-treated brush-border membrane vesicles and exhibits the same distribution volume and the same degree of nonspecific binding and trapping as in control brush-border membrane vesicles. The passive permeability properties of control and anhydro-4-epitetracycline-treated brush-border membrane vesicles are shown to be the same as measured by the time-dependence of L-glucose efflux from brush-border membrane vesicles. D-Glucose flux was measured by the equilibrium exchange procedure at constant external and internal Na+ concentrations and zero potential. Kinetic analyses of Na+-dependent D-glucose flux indicate that Vmax in anhydro-4-epitetracycline-treated brush-border membrane vesicles (79.3 +/- 7.6 nmol/min per mg protein) is significantly smaller than in control brush-border membrane vesicles (141.3 +/- 9.9 nmol/min per mg protein), while the Km values in the two cases are not different from each other (22.3 +/- 0.9 and 27.4 +/- 1.8 mM, respectively). These results suggest that Na+-dependent D-glucose carriers per se are affected by anhydro-4-epitetracycline, and that this disorder is an important underlying mechanism in the decreased Na+-dependent D-glucose uptake into anhydro-4-epitetracycline-treated brush-border membrane vesicles.

Natural history of bleeding risk in colonic diverticulosis patients: a long-term colonoscopy-based cohort study.

BACKGROUND: The natural history of bleeding risk from colonic diverticulosis remains unclear. AIM: To identify the incidence of bleeding in colonic diverticulosis patients and associated risk factors. METHODS: A cohort of 1514 patients with colonoscopy-confirmed asymptomatic diverticulosis was selected between 2001 and 2013. Age, sex and location of colonic diverticulosis (right or left side, or bilateral) were assessed. The endpoint was a bleeding event, and data were censored at the time of last colonoscopy. The cumulative and overall incidences of bleeding were estimated using the Kaplan-Meier and person-years methods. The Cox proportional hazards model was used to estimate age- and sex-adjusted hazard ratios (aHRs). RESULTS: The median follow-up period was 46 months. Bleeding events occurred in 35 patients, and the median time-to-event interval was 50 months. Kaplan-Meier analysis showed that the cumulative incidence of diverticular bleeding was 0.21% at 12 months, 2.2% at 60 months and 9.5% at 120 months. By the person-years method, the overall incidence rate of bleeding was 0.46 per 1000 patient-years. On multivariate analysis, age ≥70 (aHR. 3.7) and bilateral diverticulosis (aHR, 2.4) were significant risk factors for bleeding. CONCLUSIONS: This long-term follow-up study demonstrated that the cumulative incidence of bleeding from diverticulosis was approximately 2% at 5 years and 10% at 10 years, and the overall incidence was 0.46 per 1000 patient-years. Bilateral diverticulosis increased the risk of bleeding.

Diffuse Liver Metastasis of Small-Cell Lung Cancer Presenting as Acute Liver Failure and Diagnosed by Transjugular Liver Biopsy: A Rare Case in Whom Nodular Lesions Were Detected by Enhanced CT Examination.

Small-cell lung cancer (SCLC) is a subgroup of lung cancer with a high frequency of liver metastasis, which is a predictor of poor prognosis. Diffuse liver metastases of SCLC with no visible nodular lesions in the liver when examined using computed tomography (CT) are relatively rare; however, a few cases with rapid progression to acute liver failure that were diagnosed after death have been reported. In this paper, we report a 63-year-old man with diffuse liver metastases of SCLC that were histologically diagnosed using a transjugular liver biopsy while the patient was alive, even though no lesions were visible during a contrast-enhanced CT examination.

Effect of intrahypothalamic injection of neostigmine on the secretion of epinephrine and norepinephrine and on plasma glucose level.

We previously reported that the injection of neostigmine, an inhibitor of acetylcholinesterase, into the third cerebral ventricle of fasted rats produced hyperglycemia associated with the secretion of epinephrine and norepinephrine. However, the central nervous system site of action of neostigmine by which the plasma catecholamine and glucose concentrations were increased is not known. In this study we injected neostigmine into the ventromedial hypothalamus, lateral hypothalamus, paraventricular hypothalamus, median site of the lateral-preoptic area, lateral site of the lateral-preoptic area, anterior site of the anterior hypothalamic area, mammillary body (posterior mamillary nucleus), and cortex of anesthetized fasted rats and measured the plasma levels of glucose, epinephrine, and norepinephrine. It was found that the ventromedial hypothalamus, lateral hypothalamus, paraventricular hypothalamus, and median site of the lateral-preoptic area were involved in increasing the plasma levels of glucose and epinephrine. From this evidence we conclude that neostigmine acts on selected regions known to be involved in glucoregulation in the hypothalamus to increase the plasma levels of epinephrine and glucose.

Involvement of the hippocampus in central nervous system-mediated glucoregulation in rats.

To find out whether the hippocampus is involved in central nervous system-mediated glucoregulation, we injected saline, neostigmine, dopamine, norepinephrine, bombesin, beta-endorphin, somatostatin, and prostaglandin F2 alpha into the dorsal hippocampus in anesthetized fed rats. After injection of dopamine, norepinephrine, bombesin, beta-endorphin, somatostatin, or prostaglandin F2 alpha, the level of hepatic venous plasma glucose did not differ from that in saline-treated control rats. However, neostigmine, an inhibitor of acetylcholine esterase, caused a dose-dependent increase in the hepatic venous plasma glucose concentration. This neostigmine-induced hyperglycemia was dose-dependently suppressed by coadministration of atropine, but not by hexamethonium. Injection of neostigmine (5 X 10(-8) mol) resulted in an increase not only in glucose but also in glucagon, epinephrine, and norepinephrine in hepatic venous plasma. In bilateral adrenalectomized rats, neostigmine-induced hyperglycemia was suppressed, but the hepatic venous plasma glucose concentration still increased significantly. These results indicate that the hippocampus is involved in central nervous system-mediated glucoregulation through cholinergic muscarinic activation, partly via epinephrine secretion.

Quantitative evaluation of vascular permeability in the gerbil brain after transient ischemia using Evans blue fluorescence.

Mongolian gerbils were used to evaluate brain edema during restoration of flow following bilateral carotid occlusion for 1 h. We have modified the method for fluorometric measurement of Evans blue to monitor vascular protein leakage (vasogenic edema). The extraction of extravasated Evans blue was performed by homogenizing the whole brain in 50% trichloroacetic acid. The supernatant was diluted fourfold with ethanol and the Evans blue fluorescence was measured. The tissue blank was negligible. Evans blue content of the plasma was similarly determined and the ratio of tissue to plasma Evans blue content was calculated. Furthermore, Evans blue fluorescence was used for microscopic investigation. It is suggested that Evans blue fluorescence can be applied for quantification of protein leakage with much more sensitivity and accuracy than the colorimetric absorbance method, as well as for tissue localization of protein leakage.

Serum transforming growth factor-alpha level can be a parameter for evaluating liver regeneration after partial hepatectomy in patients with liver cancer.

Sensitive and reliable laboratory parameters are necessary to evaluate the degree of liver regeneration serially in patients after partial hepatectomy for liver cancer. We evaluated the serum levels of transforming growth factor-alpha (TGF-alpha) and hepatocyte growth factor (HGF), both of which are potent mitogens for hepatocytes, in 22 hepatectomized patients with liver cancer: 10 patients with hepatocellular carcinoma and 12 patients with metastatic liver tumors. Ten patients who underwent laparotomy for nonhepatic surgery were also studied as surgical controls. The serum TGF-alpha and HGF levels were measured by sandwich enzyme-linked immunosorbent assay techniques. Both the serum TGF-alpha and HGF levels increased after partial hepatectomy. However, there was no correlation between the levels of TGF-alpha and HGF. The maximal level of TGF-alpha achieved in each case correlated significantly with the resected liver volume and the increased volume of the remaining liver. Hepatocyte growth factor showed no such correlations. After nonhepatic surgery, the HGF level also increased significantly, while the TGF-alpha level did not. These results suggest that the serum TGF-alpha level varies depending on the regenerative stimulus to the liver, and that its increase corresponds with the degree of liver regeneration that occurs in patients after partial hepatectomy for liver cancer. In contrast, it is unlikely that the serum HGF level reflects liver regeneration. In conclusion, the serum TGF-alpha level can be used as a parameter for evaluating liver regeneration in patients who have undergone partial hepatectomy.

Primary smooth muscle tumor of the liver encasing hepatobiliary cystadenoma without mesenchymal stroma.

We describe a 59-year-old Japanese woman with a large mass of her liver encasing cystic components. Radiologic imaging showed the mass to be hypervascular, and surgical resection disclosed a white tumor. The solid portion was immunohistochemically characterized as a smooth muscle tumor. The cystic components were multilocular and lined with columnar epithelium, consistent with a hepatobiliary cystadenoma. The epithelium strongly stained for CA19-9. The subepithelial space was occupied by collagenous connective tissue interspersed with a small number of spindle-shaped cells. The cystic lesions lacked the mesenchymal stroma between the epithelium and connective tissue layer. There have been no previous reports of a hepatic smooth muscle tumor encasing a hepatobiliary cystadenoma. Because of the pathogenesis of the cystadenoma, it is possible to assume that the smooth muscle tumor also arose from the cells composing the biliary duct in association with the development of the cystadenoma.

Inhibitors of acyl-CoA:cholesterol acyltransferase. 1. Synthesis and hypocholesterolemic activity of dibenz[b,e]oxepin-11-carboxanilides.

A series of N-phenyl-6,11-dihydrodibenz[b,e]oxepin-11-carboxamides and related derivatives were prepared on the basis of structures of the reported inhibitors of acyl-CoA:cholesterol acyltransferase (ACAT). These compounds were tested for their ability to inhibit ACAT (liver microsomes from cholesterol-fed rabbits) in vitro and to decrease serum total cholesterol in cholesterol-fed golden hamsters in vivo. The structure-activity relationships in vitro were as follows. Substitution at positions 2 and 6 in the anilide resulted in potent inhibitory activity, and the potency increased with increasing size of the substituents, with maximum potency being obtained with a 2,6-diisopropyl substitution. The position of the substituent on the dibenz[b,e]oxepin ring system influenced the activity, and substitution at position 2 was critical for potent activity. The electronic effect of the substituent at position 2 does not influence activity, but bulkiness seems to be a significant factor. The lipophilicity of the compounds also plays an important role in determining ACAT inhibitory activity. Among the compounds tested, 2-bromo-N-(2,6-diisopropylphenyl)-6,11-dihydrodibenz-[b,e]++ +oxepin-11- carboxamide (33, KF17828) showed significant in vitro activity (rabbit liver microsomes IC50 = 23 nM) and the most potent in vivo activity (complete reduction in elevated serum total cholesterol levels at a dose of 10 mg/kg in hamsters).

Decrease in the fluidity of brush-border membrane vesicles induced by gentamicin. A spin-labeling study.

In our previous paper (Horio et al., Biochim Biophys Acta 858: 153-160, 1986), we reported that the addition of gentamicin in vitro to rabbit renal brush-border membrane vesicles decreases the apparent Vmax of Na+-dependent D-glucose transport without affecting the apparent Km. In the present study, we investigated the effects of gentamicin on the physical state of spin-labeled rabbit renal brush-border membranes, using electron spin resonance spectrometry. Brush-border membrane vesicles were prepared from outer cortex (mainly contains early proximal tubule) and outer medulla (containing primarily late proximal tubule), and the gentamicin toxicities in both preparations were compared. Significant decreases were observed in the membrane fluidity of 5 mM gentamicin-treated brush-border membranes. The fluidity of outer cortical brush-border membranes was affected at both 25 degrees and 35 degrees, whereas that of outer medullary membranes was affected only at 35 degrees. Two different stearic acid spin labels revealed that gentamicin affected the fluidity only in the superficial region of the membranes. We also demonstrated that the gentamicin-induced decreases in Na+-dependent D-glucose transport and in the membrane fluidity were recovered by washing gentamicin-treated brush-border membranes. We suggest that gentamicin binds to the superficial region of brush-border membranes and inhibits Na+-dependent D-glucose transport across brush-border membranes through the decrease in the membrane fluidity.

Right-to-left interatrial shunt in rats with progressive pulmonary hypertension.

A right-to-left interatrial shunt may prolong survival in patients with pulmonary hypertension presumably because of decompression of the right side of the heart. To test this hypothesis, 74 rats with monocrotaline-induced pulmonary hypertension were followed up weekly with cardiopulmonary exercise testing with a metabolic treadmill system for exercise tolerance, heart rate, oxygen uptake, carbon dioxide production, and survival until subsequent or induced death 8 weeks after monocrotaline treatment. In rats with an interatrial shunt, oxygen uptake and carbon dioxide production were higher and survival was better (n = 22, 27%) than those in rats without a shunt (n = 52, 0%; p < 0.05). For the prospective assessment of the effects of a reversed shunt, 24 other rats underwent a left superior vena cava-to-left atrial appendage anastomosis as a functional interatrial shunt (atrial septal defect group) 4 weeks after monocrotaline treatment when severe pulmonary hypertension had developed and were compared with an additional 25 rats receiving a sham operation. Both groups had exercise capacity depressed to the resting levels by 2 weeks after operation. Although transcutaneous oxygen levels decreased in response to exercise in the atrial septal defect group, uptake and carbon dioxide production stayed higher than those in the sham operation group with significantly better survival 4 weeks after operation (atrial septal defect 30% versus sham operation, 0%; p < 0.05), at which time a reversed shunt was determined with systemic embolization of intravenously infused microspheres. A right-to-left interatrial shunt, anatomic or functional, preserved basal metabolism and prolonged survival in rats with progressive pulmonary hypertension.

Nerve growth factor-mediated sexual differentiation of the rat hypothalamus.

Injection of antibody to nerve growth factor into the cerebral lateral ventricle blocked testosterone-induced behavioral defeminization of neonatal female rats. When tested as adults following ovariectomy and combined estrogen-progesterone treatment, the injected animals showed a significantly higher lordosis quotient than the testosterone-treated, normal rabbit serum-infused controls. Failure of vaginal opening and clitoral enlargement manifested the well-documented masculinizing effect of testosterone on the genitalia in the experimental as well as the control animals. Estrogen sensitivity of hypothalamic neurons which are responsible for the induction of lordosis was retained in the experimental animals. Recordings of the antidromic action potentials from neurons in the ventromedial nucleus of the hypothalamus following stimulation of the midbrain central gray revealed that estrogen decreased the antidromic activation threshold and shortened the absolute refractory period of the hypothalamic efferents along with the estrogen-induced behavioral activation in the experimental animals. In the control group, the estrogen-induced neuronal activation was lost altogether with the behavioral activation.