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Fibroblast activation protein inhibitor (FAPI) has been the focus of nuclear medicine since its introduction. With the in-depth study of FAPI tracer, its clinical application in various non-malignant diseases has also been gradually reported. Many studies have confirmed its uptake in a variety of non-malignant diseases, which indicate that FAPI tracers have good application prospects. This article reviews the latest research status and clinical application of radiolabeled FAPIs in cardiovascular diseases, rheumatic immune diseases, immunoglobulin (Ig)G4-related diseases, renal fibrosis and other non-malignant diseases at home and abroad.
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Myocardial fibrosis is an important pathological process in the development of cardiovascular diseases, which is closely related to the prognosis of patients. Activated cardiac fibroblasts (CFs) are the main effector cells, whose surface specifically overexpress fibroblast activation protein (FAP). Radionuclide-labeled FAP inhibitors (FAPIs) can specifically bind to FAP to visualize activated CFs in vivo, showing preliminary clinical application in the early diagnosis, prognosis prediction and interventional guidance of various cardiovascular diseases. This article reviews the progress of researches on the application of radionuclide-labeled FAPIs in cardiovascular diseases imaging.
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Objective:To automatically synthesize Al 18F-fibroblast activation protein inhibitor (FAPI)-74, and explore its value of clinical application. Methods:Al 18F-FAPI-74 was synthesized automatically by the commercial synthesis module CFN-MPS-100, and its yield, radiochemical purity and stability were determined. Sixteen normal Kunming (KM) mice were randomly divided into 4 groups and euthanized at 10, 30, 60 and 90 min after Al 18F-FAPI-74 injection, and the biodistribution was measured. MicroPET/CT dynamic scanning (60 min) was performed in 5 rat pancreatic tumor-bearing BALB/c nude mice to observe the tumor uptake. Al 18F-FAPI-74 PET/CT imaging was performed on 3 volunteers (1 male, 2 females; age: 37, 41, 43 years) to evaluate the clinical application value of Al 18F-FAPI-74. Results:The automated synthesis time of Al 18F-FAPI-74 was about 35 min, with the synthesis yield of (21.34±3.86)% (without attenuation correction, n=5) and the radiochemical purity more than 99%. The radiochemical purity was still more than 96% after placement at 37 ℃ for 6 h. Biodistribution in normal mice and microPET/CT dynamic scanning in tumor-bearing nude mice showed that consistently high uptake in the kidneys and bladder, and the tumor uptake was the highest at 20 min, and the maximum tumor-to-muscle ratio was 3.16±0.01 at 60 min. PET/CT imaging on volunteers showed that there was a small amount of uptake in myocardium, most organs such as the liver and lung had background uptake, and the maximum SUV max of persistent high uptake of tumor was 17.08. Conclusions:Al 18F-FAPI-74 has the advantages of simple synthesis, high yield, stable quality and good imaging performance in mice and volunteers. It is a kind of imaging agent that meets the requirements of clinical diagnosis.
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Myocardial fibrosis is one of the important pathological mechanisms in cardiac diseases. Non-invasive evaluation of fibrosis is of great clinical significance. Fibroblast activation protein (FAP) is selectively expressed in the membrane of activated fibroblasts. Radionuclide labeled FAP inhibitors (FAPI) serve as novel imaging agents, which specifically target to the process of fibrotic remodeling. This article reviews the research progress of radionuclide labeled FAPI PET imaging in cardiac diseases.
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Objective:To explore the relationship between 18F-fibroblast activation protein inhibitor (FAPI)-42 SUV max of primary gastric cancer and clinicopathological factors of patients. Methods:Fifty-one patients (31males, 20 females, age: 51(47, 65) years) with gastric cancer who underwent 18F-FAPI-42 PET/CT before surgical resection in Nanfang Hospital, Southern Medical University from February 2022 to January 2023 were analyzed retrospectively. The clinicopathological factors that might affect tumor SUV max (including gender, age, tumor location, pathological type, histological grade, Lauren classification, vascular and(or) neural invasion, programmed cell death-ligand 1 (PD-L1) expression, pathologic(p)T stage, pN stage and pTNM stage) were evaluated by the univariate analysis (Mann-Whitney U test or Kruskal-Wallis rank sum test) and multivariate analysis (multiple linear regression analysis). Results:The sensitivity of 18F-FAPI-42 PET/CT in the diagnosis of patients with primary gastric cancer was 82.35% (42/51). The diagnostic sensitivities for early gastric cancer (T1) and locally advanced gastric cancer (T2-T4) were 59.09%(13/22) and 100%(29/29), respectively. The SUV max of primary lesion was 4.90(1.71, 12.51). The univariate analysis showed that SUV max of primary gastric cancer was related to tumor location ( z=-2.00, P=0.046), pT stage ( H=36.94, P<0.001), pN stage ( z=-3.89, P<0.001), pTNM stage ( H=31.49, P<0.001) and vascular and(or) nerve invasion ( z=-5.22, P<0.001), but not related to pathological type, histological grade, Lauren typing, and PD-L1 expression ( z values: from -1.78 to -0.09, all P>0.05). pT stage was found to be a significant independent factor for SUV max in primary gastric lesion by multivariate analysis ( t=2.52, P=0.015). Conclusions:The 18F-FAPI-42 SUV max of primary tumor was related to tumor location, pT stage, pN stage, pTNM stage, and vascular and(or) nerve invasion; pT stage is an independent factor affecting tumor SUV max. The ability of 18F-FAPI-42 PET/CT to detect gastric cancer is mainly affected by pT stage.
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Fibroblast activation protein (FAP) is an important molecular marker of cancer-associated fibroblasts (CAFs). FAP is selectively expressed in more than 90% of epithelial carcinomas, but barely expressed in normal tissues. In recent years, a variety of radiolabeled molecular probes based on FAP inhibitor (FAPI) have been developed and used for imaging of malignant tumors. FAP is also highly expressed in some non-neoplastic diseases related to chronic inflammation and tissue remodeling, including arthritis, atherosclerosis, fibrosis of myocardial infarction, cirrhosis, and idiopathic pulmonary fibrosis. FAPI imaging shows a potential in these diseases. This paper reviews the current status of radionuclide labeled FAPI and the application of which in non-neoplastic diseases.
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Objective:To automatically synthesize Al 18F-1, 4, 7-triazacyclononane-1, 4, 7-triacetic acid (NOTA)-fibroblast activation protein inhibitor (FAPI)-04, perform PET/CT imaging in vivo, and evaluate its diagnostic efficacy on tumors. Methods:Al 18F-NOTA-FAPI-04 was produced in All-in-one automatic synthesis module and its quality control was conducted by high performance liquid chromatography (HPLC) equipped with a radioactive detector. Al 18F-NOTA-FAPI-04 PET/CT imaging was performed in normal BALB/c mice ( n=3) and 4T1 breast cancer models ( n=3) to determine its biodistribution. Then Al 18F-NOTA-FAPI-04 and 18F-FDG PET/CT imaging were performed in a hepatocellular carcinoma patient (male, 51 years old). Results:The synthesis time of Al 18F-NOTA-FAPI-04 was about 35 min, and the radiochemical yield was (25.2±1.9)% (attenuation correction, n=3). The product was colorless transparent solution with pH value of 7.0-7.5, and the specific activity was (46.11±3.07) GBq/μmol (attenuation correction, n=3). The radiochemical purity was above 99.0% and was still above 98.0% at room temperature after 6 h. PET/CT imaging in mice showed that physiological uptake of Al 18F-NOTA-FAPI-04 was mainly in biliary system and bladder, and Al 18F-NOTA-FAPI-04 highly concentrated in tumor xenografts. PET/CT imaging in the patient showed that Al 18F-NOTA-FAPI-04 obtained high tumor background ratio (TBR) values of 4.1, 8.9, 5.4, 4.8, 2.2 in parasternal lymph nodes, anterior diaphragmatic lymph nodes, hilar lymph nodes, pancreaticoduodenal ligament lymph nodes, abdominal aortic lymph nodes, respectively, while TBR values were 1.0, 2.8, 5.0, 2.1, 1.1 by 18F-FDG. Conclusions:Al 18F-NOTA-FAPI-04 can be synthesized with short time, high radiochemical yield and good stability using All-in-one module. Al 18F-NOTA-FAPI-04 PET/CT imaging has high contrast and excellent diagnostic efficacy on tumors.
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Objective:To investigate the impact of trigger timing of gonadotropin- releasing hormone (GnRH) antagonist regimen for infertility patients of various ages.Methods:This was a retrospective study, 1 529 infertility patients who receiving GnRH antagonist regimen in Chongqing Health Center for Women and Children from January 2017 to December 2018 were divided into the advance trigger group and the standard trigger group, and further divided into three subgroups according to age:<35 years, 35-40 years,>40 years. The number of retrieved oocytes and transplantable embryos, the clinical pregnancy rate and the live birth rate among patients in the advance trigger group and standard trigger group in various age subgroups were compared.Results:(1) The gonadotropin (Gn) days among the three age subgroups were significantly shorter in the advance trigger group compared to the same-aged standard trigger group (all P<0.01), but only in the 35-40 years and >40 years subgroups, the Gn doses in the advance trigger group [(2 702±551) and (2 780±561) U] were significantly less than those in the standard trigger group (all P<0.01). In the <35 years subgroup, the number of oocytes retrieved and transplantable embryos of the advance trigger group (6.6±4.8 and 2.6±2.7) were significantly less than those of the standard trigger group (all P<0.01), but there was no difference in the number of top-quality embryos ( P=0.580); however, in the 35-40 years and >40 years subgroups, there were no significant differences between advance and standard trigger groups in terms of the afore mentioned 3 indicators (all P>0.05), only the numbers of top-quality embryos in the advance trigger group (0.6±1.0 and 0.6±0.9) were significantly higher than those in the standard trigger group (all P<0.01). (2) In the <35 years and 35-40 years subgroups, no significant differences were noted between the advance trigger group and standard trigger group with regard to the clinical pregnancy rate and live birth rate (all P>0.05); but in the >40 years subgroup, the clinical pregnancy rate of the advance trigger group was significantly higher than that of the standard trigger group [33.0% (30/91) vs 19.2% (25/130), P=0.020], and there was no statistical difference in the live birth rate ( P=0.064). (3) Multivariate logistic regression analysis showed that trigger timing was an independent predictor of clinical pregnancy rate in the >40 years subgroup ( OR=0.334, 95% CI: 0.119-0.937, P=0.037), but not an independent predictor of live birth rate ( P>0.05). Conclusions:Advance trigger in the GnRH antagonist protocol for infertility patients >40 years old could effectively reduce Gn times and Gn dosage, increase the number of top-quality embryos, and improve the clinical pregnancy rate. Therefore, compared with patients ≤40 years of age, patients >40 years might benefit more from advance trigger.
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Objective:To compare the clinical utility of 18F-fibroblast activating protein inhibitor (FAPI)-42 and 18F-fluorodeoxyglucose (FDG) PET/CT imaging in newly diagnosed lung cancer patients. Methods:From May 2020 to September 2021, the images of 43 lung cancer patients (32 males, 11 females, age: 37-80 years) who pathologically confirmed and received 18F-FDG and 18F-FAPI-42 PET/CT within 2 weeks in the First Affiliated Hospital of Guangzhou Medical University were prospectively analyzed. The maximum standardized uptake value (SUV max) of 18F-FDG and 18F-FAPI-42 and the number of lesions detected by 2 imaging methods were compared by using paired t test and Wilcoxon rank sum test. Results:The 43 newly diagnosed lung cancer patients included 35 adenocarcinoma, 2 squamous cell carcinoma, 4 small cell lung cancer, and 2 high-grade neuroendocrine tumors. 18F-FAPI-42 had a very high tumor uptake (SUV max: 12.24±3.97) and lesion detection rate (positive rate: 100%(37/37)) in primary lung adenocarcinoma and squamous cell carcinoma. The uptake of 18F-FAPI-42 in lymph node (10.13±5.43), pleura (6.75(4.96, 8.58)) and bone lesion (7.18(4.33, 9.66)) were significantly higher than those of 18F-FDG (6.35±3.30, 2.69(1.81, 5.00), 4.38(2.96, 6.36); t=12.19, z values: 5.47, 5.79, all P<0.001). In lung adenocarcinoma and squamous cell carcinoma, although the uptake of 18F-FAPI-42 in brain metastases was significantly lower than that of 18F-FDG (0.72(0.15, 1.82) vs 6.53(4.65, 9.34); z=6.42, P<0.001), the tumor/background (T/B) ratio was significantly higher than that of 18F-FDG (3.54(1.15, 14.88) vs 0.96(0.77, 1.04); z=6.05, P<0.001). In lung adenocarcinoma and squamous cell carcinoma, the number of lesions detected by 18F-FAPI-42 PET/CT was significantly more than that of 18F-FDG (lymph node: 6.0(2.3, 11.5) vs 4.5(2.0, 10.8); brain: 2.0(1.0, 3.0) vs 0.0(0.0, 0.0); pleura: 6.0(2.8, 10.0) vs 4.0(0.8, 5.5); z values: 2.16, 3.10, 2.04, all P<0.05). However, in high-grade neuroendocrine tumors and small cell lung cancer, the SUV max of 18F-FAPI-42 in primary lesions (8.05±2.60), lymph node lesions (5.98±2.21) and brain lesions (0.44(0.13, 0.82)) were lower than those of 18F-FDG (16.28±5.17, 12.30±5.47, 4.94(4.84, 6.25); t values: 3.58, 7.52, z=3.06, all P<0.05). Conclusions:In lung adenocarcinoma and squamous cell carcinoma, 18F-FAPI-42 has a very high tumor uptake and lesion detection rate in primary tumor. In addition, compared with 18F-FDG PET/CT, 18F-FAPI-42 PET/CT shows clearer tumor contours and more lesions. Therefore, 18F-FAPI-42 is more suitable for preliminary staging of lung adenocarcinoma and squamous cell carcinoma than 18F-FDG, while the opposite is true in small cell lung cancer and high-grade neuroendocrine tumors.
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BACKGROUND: The present experiment was conducted to identify the cooperative effect of serine histogranin (SHG) and noradrenaline in alleviating peripheral neuropathic pain. METHODS: Chronic constriction injury of the right sciatic nerve was used to induce chronic neuropathic pain. For drug delivery, a PE10 tube was inserted into the subarachnoid space. Acetone drops and a 44degrees C water bath were used to evaluate the cold and heat allodynia, respectively. Placing and grasping reflexes were used to assess the locomotor system. RESULTS: SHG at 0.5 and 1 microg significantly (P < 0.05) decreased the thermal allodynia. The cold allodynia was also significantly reduced by intrathecal injections of 0.5 (P < 0.05) and 1 microg (P < 0.001) of SHG. 1 microg of noradrenaline, but not 0.5 microg, significantly alleviated the cold (P < 0.01) and thermal (P < 0.05) allodynia. The ameliorating effect of noradrenaline or SHG disappeared when the two compounds were administrated in equal concentrations. A significant difference (P < 0.01 in the acetone and P < 0.05 in the heat) was observed in the groups under equal doses of the two compounds, with a lower effectiveness of the combination therapy. CONCLUSIONS: Our findings suggest that the simultaneous administrations of noradrenaline and SHG do not result in synergistic analgesia, and combination therapy may not be a good approach to the treatment of chronic neuropathic pain syndrome.
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Acetone , Analgesia , Baths , Constriction , Hand Strength , Hot Temperature , Hyperalgesia , Injections, Spinal , N-Methylaspartate , Neuralgia , Norepinephrine , Reflex , Rodentia , Sciatic Nerve , Serine , Subarachnoid Space , WaterABSTRACT
Introducción. No existen reportes sobre las variaciones en la secuencia de los genes blanco de los medicamentos anti- Toxoplasma en aislamientos provenientes de Suramérica. Objetivo. Clonar y secuenciar los genes de la dihidrofolato-reductasa ( dhfr ) y la dihidropteroato-sintetasa ( dhps ) de la cepa de referencia RH y de dos aislamientos colombianos de Toxoplasma gondii. Materiales y métodos. Se obtuvieron dos aislamientos de T. gondii en líquido céfalorraquídeo de pacientes colombianos positivos para HIV con toxoplasmosis cerebral. Se extrajo el ADN de los genes dhfr y dhps y se amplificaron mediante reacción en cadena de la polimerasa (PCR). Los productos fueron clonados en el vector pGEM-T y secuenciados. Resultados. Se encontró un cambio de adenina por guanina (A « G) en la posición 235 del exón 2 del gen dhps , dos cambios de guanina por citocina (G « C) en las posiciones 259 y 260 y un cambio de timina por guanina (T « G) en la posición 371 del exón 4 del gen dhps. Por análisis bioinformático, en este último exón se identificó un polimorfismo no sinónimo en la región codificante, que podría llevar al cambio de una Glu (CAA o CAG) por una His (codificada por los codones AAU o AAC). Se calculó el modelo estructural de la enzima dihidropteroato-sintetasa (DHPS) de T. gondii y se identificaron las modificaciones en la estructura secundaria ocasionadas por las mutaciones. Conclusiones. La metodología estandarizada puede servir como base para la búsqueda de polimorfismos en muestras de pacientes con diferentes manifestaciones clínicas de toxoplasmosis y para establecer su posible relación con los cambios en la sensibilidad a los antifolatos y la reacción al tratamiento.
Introduction: There are no reports describing polymorphisms in target genes of anti- Toxoplasma drugs in South American isolates. Objective: This study sought to perform cloning and sequencing of the dihydrofolate reductase ( dhfr ) and dihydropteroate-synthase ( dhps ) genes of the reference Rh strain and two Colombian isolates of Toxoplasma gondii . Materials and methods: Two isolates were obtained from the cerebrospinal fluid of HIV-infected patients with cerebral toxoplasmosis. A DNA extraction technique and PCR assay for the dhfr and dhps genes were standardized, and the products of amplification were cloned into Escherichia coli and sequenced. Results: One polymorphism (A « G) was found at position 235 of exon 2 in the dhps gene. In addition, two polymorphisms (G « C) at positions 259 and 260 and one polymorphism (T « G) at position 371 within exon 4 of the dhps gene were detected. In this last exon, a bioinformatic analysis revealed a non-synonymous polymorphism in the coding region that could lead to the substitution of Glu (CAA or CAG) for His (encoded by codons AAU or AAC). A structural model of the T. gondii DHPS protein was calculated, and the results revealed modifications in secondary structure due to mutations. Conclusions: The methods described in this study can be used as a tool to search for polymorphisms in samples from patients with different clinical manifestations of toxoplasmosis and to examine their relationship with the therapeutic response.
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Animals , Humans , Male , Mice , Dihydropteroate Synthase/genetics , Polymorphism, Single Nucleotide , Protozoan Proteins/genetics , Tetrahydrofolate Dehydrogenase/genetics , Toxoplasma/enzymology , AIDS-Related Opportunistic Infections/cerebrospinal fluid , AIDS-Related Opportunistic Infections/parasitology , Amino Acid Substitution , Base Sequence , Cloning, Molecular , Colombia , Cerebrospinal Fluid/parasitology , DNA, Protozoan/genetics , DNA, Recombinant/genetics , Dihydropteroate Synthase/chemistry , Exons/genetics , Models, Molecular , Molecular Sequence Data , Protein Conformation , Protozoan Proteins/chemistry , Sequence Alignment , Sequence Homology, Nucleic Acid , Toxoplasma/genetics , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/parasitology , Toxoplasmosis, Cerebral/cerebrospinal fluid , Toxoplasmosis, Cerebral/parasitologyABSTRACT
ADP-ribosyl cyclase (ADPR-cyclase) produces a Ca2+-mobilizing second messenger, cyclic ADP- ribose (cADPR), from beta-NAD+. A prototype of mammalian ADPR-cyclases is a lymphocyte antigen CD38. Accumulating evidence indicates that ADPR-cyclases other than CD38 are expressed in various cells and organs. In this study, we discovered a small molecule inhibitor of kidney ADPR-cyclase. This compound inhibited kidney ADPR-cyclase activity but not CD38, spleen, heart or brain ADPR-cyclase activity in vitro. Characterization of the compound in a cell-based system revealed that an extracellular calcium-sensing receptor (CaSR)- mediated cADPR production and a later long-lasting increase in intracellular Ca2+ concentration ([Ca2+]i) in mouse mesangial cells were inhibited by the pre-treatment with this compound. In contrast, the compound did not block CD3/TCR-induced cADPR production and the increase of [Ca2+]i in Jurkat T cells, which express CD38 exclusively. The long-lasting Ca2+ signal generated by both receptors was inhibited by pre-treatment with an antagonistic cADPR derivative, 8-Br-cADPR, indicating that the Ca2+ signal is mediated by the ADPR-cyclse metabolite, cADPR. Moreover, among structurally similar compounds tested, the compound inhibited most potently the cADPR production and Ca2+ signal induced by CaSR. These findings provide evidence for existence of a distinct ADPR-cyclase in the kidney and basis for the development of tissue specific inhibitors.
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Rats , Mice , Humans , Animals , Receptors, Calcium-Sensing/metabolism , Rats, Sprague-Dawley , Kidney/enzymology , Enzyme Inhibitors/chemistry , Cyclic ADP-Ribose/metabolism , Cell Line , Calcium Signaling , Azo Compounds/chemistry , ADP-ribosyl Cyclase/antagonists & inhibitorsABSTRACT
[Objective] To explore the anti - inflammatory mechanism of sinomenine, a monomer alkaloid from Caulis Sinomenii. [ Methods] In - vitro enzyme was applied to observe the effect of sinomenine on cyclooxygenase (COX) 1 and COX 2. [Results] Sinomenine at the concentration of 1 - 250 ?mol/L could inhibit the formation of PGE2 induced by COX 2 in a good dose - effect manner. [Conclusion] Sinomenine selectively inhibiting the activity of COX 2 may be the anti - inflammatory and anagesic mechanism of sinomenine with less gastrointestinal adverse effect.
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Objective: To evaluate the effect of platelet activating factor(PAF) antagonism on the blood content in the random survival flap. Methods: A lipophilic PAF receptor antagonist BN52021 was administered to treat flaps through a local subcutaneous injection route 30 min prior to transplantation. The flaps were imaged in situ by a gamma camera. Results: The PAF receptor antagonist significantly augmented the accumulation of radioactivity of middle and end part within treated flaps( P
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Objective To investigate the protective effects of pretreatment with valsartan, an angiotensin Ⅱ type 1 receptor blocker, on the brain against ischemia-reperfusion (I/R) injury. Methods Thirty-six healthy male C57BL/6J mice aged 10-12 weeks weighing 20-25 g were randomly divided into 2 groups (n - 18 each): valsartan group (V) and control group (C). In group V valsartan 2 mg?kg-1 dissolved in 2.5% NaHCO3 100 ?l was given intraperitoneally (i.p. ) every day for 10 days before experiment while in group C 2.5% NaHCO3 100?l without valsartan was given. The animals were anesthetized with intraperitoneal pentobarbital 40 mg?kg-1. Middle cerebral artery occlusion (MCAO) was produced by inserting an 8-0 nylon thread with rounded end into the left internal carotid artery and advancing it cranially until resistance was felt. MCAO was maintained for 1 h. The nylon thread was then withdrawn for reperfusion. A laser doppler blood flow detector (Omegaflo FLO-C1, Omegawave Co, Netherlands) was used to detect local cerebral blood flow (LCBF) at central and marginal infarct area [LCBF (%) = LCBF during I/R / baseline LCBF ? 100% ]. The model of MCAO was considered established when LCBF at central infarct area was 20% lower than the baseline value. LCBF was measured 10 min before MCAO (T0, baseline), as soon as MCA was occluded (T1) at 10, 30, 50 min of ischemia (T2-4) and at 10, 30, 60 min of reperfusion (T5-7) . MAP was measured immediately before valsartan administration, at T0 and T5. Neurological function deficit (NFD) was evaluated and scored (0 = no deficit, 4 = worst result) at 23 h after reperfusion was started . After evaluation of NFD the animals were anesthetized again and killed. The brains were removed. Cerebral water content was measured [cerebral water content (%) = (wet weight - dry weight) / wet weight ? 100%]. Infarct area was measured. Mortality rate was recorded.Results Pretreatment with valsartan did not affect MAP significantly but significantly reduced infarct area, brain water content, NFD and mortality rate and improved focal cerebral blood flow after MCAO. Conclusion Valsartan pretreatment can decrease cerebral infarct area induced by MCAO through improvement of focal cerebral blood flow after MCAO.