Clinical Hemorheology and Microcirculation - Volume 23, issue 2,3,4

Authors: Zhang, Jian | Fu, Shiming | Liu, Shuying | Mao, Ting | Xiu, Ruijuan

Article Type: Research Article

Abstract: This paper aimed to investigate the therapeutic effect of an extract of Ginkgo biloba leaves (EGb 761) on hypertension and its possible mechanisms in the view of cerebral microcirculation. Twenty normotensive rats and 24 SHR rats were used. Surgical preparation was made to produce a cranial window for observation of the capillary network on the cerebral cortex. The intravital videomicroscopy equipped with digital image processing system and laser Doppler flowmeter were used for this study. The arterial blood pressure, red cell velocity (V), microvacular diameter (D), number of open capillaries (OCN), circulating endothelial cells (CEC) in blood, relative blood flow …(Flow) and frequency (Fc), amplitude (AMP) of vasomotion were measured. The obtained data were compared between EGb‐treated rats that received per os 100 mg/kg/d for 9 days and placebo control rats. Untreated SHR rats showed very severe dysfunction in the microcirculation with high blood pressure (213±16.7 mmHg). The blood pressure decreased significantly to 153±20 mmHg in EGb‐treated SHRs group, compared with those of untreated rats (p<0.01). Both normotensive and hypertensive rats increased the blood flow velocity and LDF flow after EGb‐treatment. The vasomotion property, the CEC and OCN changed greatly in EGb‐treated SHR rats, but no significant difference was observed in normotensive rats. It was suggested that EGb 761 had therapeutic effect on SHR rats by increasing blood perfusion, regulating vasomotion function, opening efficiently capillaries and releasing the peripheral resistance. The injured vascular endothelium of SHR rats was also partly reversed by EGb‐treatment. It was concluded that EGb 761 could be used to regulate hypertension and to protect the cerebral microcirculatory function. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 133-138, 2000

Authors: Sun, Bao‐Liang | Xia, Zuo‐Li | Yang, Ming‐Feng | Qiu, Ping‐Ming

Article Type: Research Article

Abstract: This study aimed to investigate the protective effects of Ginkgo biloba extract on cerebral vasospasm and neural damage following subarachnoid hemorrhage (SAH) in rats. It was found that the regional cerebral blood flow decreased immediately and persistently after SAH in SAH rats. The latency of somatosensory evoked potential delayed progressively. The nitric oxide levels in serum and brain tissue decreased and increased, respectively, after SAH. Ginkgo biloba extract effectively antagonized the changes of above parameters. It was concluded that somatosensory evoked potential is useful for the judgement of cerebral ischemic damage during cerebral vasospasm after SAH. Decrease in serum nitric …oxide and increase in brain tissue nitric oxide are important factors leading to cerebral vasospasm and neural damage, respectively, after SAH. Ginkgo biloba extract relieves cerebral vasospasm and cerebral ischemic damage by reversing the pathological alteration of nitric oxide. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 139-144, 2000

Authors: Zhao, Hong | Zhu, Cheng | Li, Xiufeng | Dong, Xi | Zhuang, Fengyuan | Wang, Xiong | Stoltz, Jean‐François

Article Type: Research Article

Abstract: The aim of this work was to study the effects of tetramethylpyrazine (TMP) on the interaction between lymphocyte function‐associated antigen‐1 (LFA‐1) and intercellular adhesive molecule‐1 (ICAM‐1) by micropipette technique. A pair of cells, i.e., a human lymphocyte or a SKW‐3 cell (human T cell leukemia), LFA‐1 was expressed on which cellular surfaces, and a RBC coupled with ICAM‐1, were the carriers for LFA‐1 and ICAM‐1. The adhesion probabilities of this pair of cells were mediated by specific interactions between ICAM‐1 and LFA‐1. Phytohemagglutinin (PHA) stimulation resulted in the significant increase in the adhesion probability compared to the resting lymphocyte. TMP …treatment can inhibit such increase and even make the adhesion probability lower than the resting state. While the LFA‐1 expression has not changed significantly with PHA stimulation or with TMP treatment, which indicated that TMP inhibiting effects was realized by a possible conformation change. Show more

Keywords: Leukocyte adhesion, ICAM‐1/LFA‐1, micropipette, tetramethylpyrazine

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 145-151, 2000

Authors: Minamiyama, M. | Chang, L.‐G.

Article Type: Research Article

Abstract: Effects of tetramethylpyrazine (TMP) and that of extracts of Charthamus tinctorius L. (CTL) on the macro‐ and microcirculation in rabbit mesentery were studied. The intestinal arterial blood flow (Qa) was measured using an electromagnetic flowmeter, together with the arterial blood pressure (Pa). The inner diameter and red cell velocity in single arteriole in the mesentery were measured by a video‐image technique and a dual‐slit photometric method, respectively. Using the measured diameter and red cell velocity, the arteriolar blood flow (Qm) was calculated. Both the Qa and Qm decreased when Pa was decreased after the intravenous administration of TMP, CTL, Nicardipine, …Phentolamine and acetylcholine (Ach). Changes in Qa and Qm with changes in Pa were analyzed, and it was found that (i) both the Pa–Qa and Pa–Qm curves, during the administration of TMP or CTL, show different patterns from those during the administration of Nicardipine or Phentolamine; (ii) the Pa–Qa and Pa–Qm curves after the administration of TMP or CTL show similar patterns with those after the administration of Ach. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 153-158, 2000

Authors: Tigno, Xenia T. | Gumila, Elinor

Article Type: Research Article

Abstract: Water extract fractions of leaves from Artemisia vulgaris L. (commonly known as mugwort) were tested for their effects on tissue damage brought about by ischemia‐reperfusion injury in the rat mesentery. Male Sprague–Dawley rats, 200–300 grams in weight were divided into two groups, control and treatment (AV) group. All rats were anesthetized with ketamine HCl administered intramuscularly, tracheotomized and cannulated in one carotid artery and one jugular vein. After a midline abdominal incision, the mesenteric area was exteriorized and observed using videomicroscopy. After baseline observations of systemic blood pressure, heart rate, venular diameters and leukocyte adhesion along venules, the mesenteric artery …and vein were occluded for 10 minutes. Prior to occlusion, A. vulgaris‐treated animals were given a bolus injection of a 1% w/v solution of extracts, while the control group received saline. Monastral Blue dye was also administered before the occlusion at a dose of 30 mg/kg via the jugular vein in order to assess transendothelial leakage. Hemodynamic and cellular parameters were measured immediately after the release of occlusion and at 10 minute intervals thereafter. Results show that the extracts had no significant effects on mean blood pressures and heart rates, but appeared to significantly reduce leukocyte adherence and transendothelial leakage while improving flow in the ischemia‐reperfused organ. The extract fractions contain yomogin, which has been previously shown to inhibit iNOS activity, and may therefore explain the anti‐inflammatory property of the plant. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 159-165, 2000

Authors: Tigno, Xenia T. | de Guzman, Florecita | Flora, Anna Ma. Theresa V.

Article Type: Research Article

Abstract: Artemisia vulgaris L. is widely used in the Philippines for its anti‐inflammatory properties. The plant was cultivated and mature leaves were collected and washed. The dried leaves were extracted with both distilled water and chloroform. NMR data were obtained using a Varian Unity 500 MHz spectrophotometer. High and low‐resolution mass spectra were obtained on a Finnigan MAT 96 high resolution gas chromatograph/mass spectrophotometer with a MAT ICIS operating system. The leaves yielded 2 sesquiterpene lactones and a novel aromatic compound. Two partition fractions from the aqueous extracts and four partition fractions from the chloroform extracts were tested on male Sprague–Dawley …rats using both the in situ mesenteric circulation and the isolated perfused mesentery. In the isolated perfused rat mesentery, administration of 10% w/v solutions of water extract fractions FGN 63‐1 and FGN 63‐2 of A. vulgaris were highly effective in reversing the hypertensive action induced by norepinephrine, but they did not change the regional mesenteric pressures when given at baseline. In the intact rat, injection of 10 mg/ml of FGN 63‐1 and chloroform extract FGN 64‐2 did not significantly alter baseline blood pressures, but were able to reverse the increase in mean systolic and diastolic pressures induced by norepinephrine. The same fractions did not exert any significant effect on heart rate in either the normotensive or hypertensive states. The present data suggest that aqueous and chloroform extracts from leaves of A. vulgaris have anti‐hypertensive actions but have no significant effects on cardiovascular hemodynamics under basal conditions. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 167-175, 2000

Authors: Iwo, Maria Immaculata | Soemardji, Andreanus Andaja | Retnoningrum, Debbie Sofie | Sukrasno, | U, Uu Mar.

Article Type: Research Article

Abstract: The immunostimulating effect of “Pule” (Alstonia scholaris (L.) R.Br., Apocynaceae) bark extracts was studied in BALB/c mouse. The extracts were administered orally, once a day for 7 consecutive days. The results showed that at the same doses (50, 100 and 200 mg/kg b.w.) the aqueous extract had higher phagocytic index (1.39–1.79) than the ethanolic extracts (0.81–0.93) in normal mice. The aqueous extract at 50 mg/kg b.w. also enhanced phagocytic activity of immunosuppressed mice significantly (P<0.01). At 50 and 100 mg/kg b.w. the extract prevents the decrease of immune system induced by prednisone. The aqueous extract at 100 mg/kg b.w. increased …lytic activity of peritoneal exudate cells against Escherichia coli significantly (P<0.05). At the doses of 50 and 100 mg/kg b.w. the aqueous extract had no effect on primary antibody level. The aqueous extract at 50 mg/kg b.w. induced the cellular immune response while at 100 mg/kg b.w. inhibited the delayed type of hypersensitivity reaction. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 177-183, 2000

Authors: Sukardiman, | Darwanto, Agus | Tanjung, Mulyadi | Darmadi, Made Oka

Article Type: Research Article

Abstract: The cytotoxic activity of flavonoid from Temu Kunci (Kaempferia pandurata) was tested by brine shrimp lethality test and cell culture of human mammary carcinoma. This compound is pinostrobin, and has antitumor activity. However, the critical biochemical target of these pinostrobin has not been identified. In our present studies, we used DNA topoisomerase I which was isolated from human tumor. This result showed that pinostrobin inhibited DNA topoisomerase I activity. Pinostrobin may be interfere with DNA breakage‐reunion reaction by stabilizing a key covalent intermediate between DNA and the enzyme, resulting in the cleavage DNA. An inhibition in the activity of DNA …topoisomerase I is suggesting that this could be a possible mechanism of pinostrobin from Temu Kunci for the cytotoxicity observed in cell culture of human mammary carcinoma. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 185-190, 2000

Authors: Niimi, Hideyuki | Yamaguchi, Saburo | Hu, Qing‐Hua | Zhuang, Feng‐Yuan

Article Type: Research Article

Abstract: The present experiment attempted to evaluate the effect of electrical acupuncture on the cerebral microcirculation in anesthetized rats, using fluorescence videomicroscopy. Changes in the pial arteriolar diameter under acute hemorrhagic hypotension were examined quantitatively. The present results suggest that acupuncture may be effective in improving the cerebral microcirculation in hemorrhagic hypotension.

Keywords: Acupuncture, hemorrhagic hypotension, vasodilation, cerebral microcirculation

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 191-195, 2000

Authors: Oda, Masaya | Han, Jing‐Yan | Nakamura, Masahiko

Article Type: Research Article

Abstract: Functional and morphological alterations of microvascular endothelial cells (ECs) would lead to microcirculatory disturbances, thereby providing a basis for the development of a disease state. Clinically endotoxemia frequently encountered in a variety of diseases is considered to be a trigger to develop the microcirculatory disorders such as disseminated intravascular coagulation (DIC) and multiple organ failure (MOF), both of which feature the end stage of severe systemic disease. Experimentally intravital microscopy reveals that continuous venous infusion of endotoxin (LPS) causes a low flow state in the rat mesenteric microcirculatory unit. By vital stain with monastral blue B (MBB), the microvascular ECs …are focally positive for MBB at the postcapillary venular site, where leukocytes adhere and extravasate. As shown in the histamine‐induced diapedesis by transmission electron microscopy, the MBB‐positve venular ECs may correspond to the contracted ECs, enabling the polymorphonuclear leukocytes and erythrocytes to extravasate through the widened gaps between the contracted ECs. Actin filaments proven in the microvascular ECs by electron microscopy may play a modulating role in this neutrophil diapedesis. In the process of gastric ulcer formation under restrained stress to the rat, the ECs of microvessels in the gastric mucosa, particularly of the mucosal capillaries and postcapillary venules directly innervated by the cholinergic nerves, are altered by the stress‐induced overstimulation of the autonomic nerves, inducing the diapedesis of leukocytes and erythrocytes followed by hemorrhagic and ischemic injuries in the gastric mucosa. Liver cirrhosis also accompanies endotoxemia. The most prominent electron microscopic alterations of hepatic microvasculature are a decrease of hepatic sinusoidal endothelial fenestrae (SEF) both in diameter and in number, and the formation of basement membranes beneath the hepatic sinusoidal ECs. These ultrastructural changes would be induced by a most potent vasoconstrictor endothelin (ET)‐1 through the overexpressed ETA and ETB receptors on the hepatic stellate cells and the sinusoidal ECs, contributing to the development of portal hypertension as well as to the disturbance in excretion of endotoxin into the bile canaliculi via the hepatocytes from the circulating sinusoidal blood to prevent endotoxemia. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 23, no. 2,3,4, pp. 199-211, 2000