Search PubMed⌕ Search

Biomedical subjects

H Honda

Publications and source records attributed to H Honda.

At least 415 records · Page 23Linked to original sources

(Pyridoxylated hemoglobin)-(polyoxyethylene) conjugate solution as blood substitute for normothermic whole body rinse-out.

In order to investigate a new possibility for artificial blood with oxygen-carrying capability to be applied to other than mere supplementation, normothermic whole body rinse-out in which artificial blood deriving from perfluorochemical emulsion, Fluosol-DA 20% (Green Cross Co., Ltd., Osaka, Japan) or stabilized hemoglobin solution, (pyridoxylated hemoglobin)-(polyoxyethylene) conjugate solution (Ajinomoto Co., Ltd., Tokyo, Japan) were used as rinsing fluid for a blood purification experiment. Replacement either with approximately 150 ml/kg of Fluosol-DA or stabilized hemoglobin solution showed effective removal of digoxin at a reduction rate of 96.3% or 92.2%, respectively. However, when Fluosol-DA was used, a certain amount of perfluorochemical should be retrieved by centrifugation to avoid a possible toxic effect on the reticulo-endothelial system. Even though 3 out of 6, and 3 out of 8 dogs, respectively, survived for a long period after the procedure, the experimental dogs were very susceptible to infection.

Animals↗

Long term liver preservation using artificial blood substitutes.

Twenty-four hour hypothermic perfusion preservation of the liver was aimed using an artificial blood substitutes. A canine liver was harvested and preserved using originally designed perfusates. In group 1, Perfluorotributylamine solution (Oxypherol solution) was used. In group 2, (Pyridoxylated hemoglobin)-(Polyoxyethylene) conjugate solution (Stabilized Hemoglobin, PHP-1). In group 3 and in group 4, modified Stabilized hemoglobin, PHP-3 and PHP-4 was used. After the preservation, each liver was transplanted orthotopically. Postoperative graft function was estimated the following parameter, such as bile excretion, consciousness level, activated clotting time, and survival rate. In group 1 and group 2, improvement of such factors were not fully observed. On the contrary, in group 3 and 4, complete recovery of the function was seen and in group 4, longer survival was obtained. PHP solution was considered suitable perfusate for liver preservation.

Animals↗

The left ventricular vibration mode in the ventricular transfer function method and at the moment of the first heart sound.

Several investigators have aimed to clarify the patient's left ventricular (LV) physical properties by free vibration analysis of heart sound. Recently we have developed a transfer function (TF) method to calculate the LV viscoelasticity. To clarify whether this TF method and a clinical first heart sound (1 HS) analysis are based on the identical ventricular vibration mode analysis, we examined (1) the visualized LV vibration image in the TF method and (2) the quantitative relationship between the peak frequency of the 1 HS spectrum and that of TF curve in the early and late phase of the 1 HS. Isolated isovolumic potassium arrested canine left ventricles were used to visualize the vibration mode in describing the TF (N = 2). Examination of stroboscopically illuminated, slow-motion images revealed the oscillation of the ventricle to be of mode 2 behavior. To analyze the quantitative relation between the TF method and 1 HS analysis we used ten open-chest dogs. The correlation was good (r = 0.917) when the peak frequency of the TF curve at the early phase of the 1 HS was compared to the peak frequency of the 1 HS. We concluded that both the TF method and 1 HS analysis were based on the common, second-order ventricular vibration mode. Therefore, some information on the ventricular physical properties suggeted by the TF method could also be included in the clinical data obtained by 1 HS analysis.

Animals↗

A possible mechanism on the potentiating vascular effect of coadministration of ifenprodil tartrate and calcium hopantenate: a study in the internal carotid artery.

Recently, it has been proposed that the combined administration of ifenprodil tartrate and calcium hopantenate might produce a beneficial synergistic effect in the treatment of cerebrovascular diseases. To further examine this clinical phenomena, the blood flow in the internal carotid arteries of the rat and the isometric tension of canine internal carotid arteries were measured with a transit-time ultrasonic volume flowmeter and a force transducer, respectively. Ifenprodil tartrate produced a sustained increase in the internal carotid arterial blood flow of rats, while calcium hopantenate had no effect. However, the increase in the internal carotid arterial blood flow induced by ifenprodil tartrate was significantly enhanced by calcium hopantenate. Ifenprodil tartrate caused a dose-related relaxation of K+-induced contractions in the isolated canine internal carotid arteries, while calcium hopantenate had no effect. The dose-response curve of ifenprodil tartrate was shifted to the left by pre-incubation in calcium hopantenate. Ifenprodil tartrate inhibited the K+-induced Ca2+ uptake in the canine internal carotid arteries, and the inhibition induced by ifenprodil tartrate was significantly enhanced by calcium hopantenate. These results suggest that the observed enhancement by calcium hopantenate of the ifenprodil tartrate effect on the internal carotid arterial blood flow was due to increased vascular myorelaxation resulting from the influence of calcium hopantenate on the Ca2+ movement.

Animals↗

A possible mechanism on the potentiated vascular effect of coadministration of ifenprodil tartrate and calcium hopantenate: a study in the basilar and vertebral arteries.

In our earlier report [Shibuya et al. in press], we demonstrated the partial mechanism of the synergism between ifenprodil tartrate and calcium hopantenate on cardiovascular diseases. The mechanisms of the synergistic effects in the basilar and vertebral arteries were further studied in this paper using our described methods. Ifenprodil tartrate produced a sustained increase in the vertebral arterial blood flow of rats, while calcium hopantenate. Ifenprodil tartrate caused dose-related relaxation of K+-induced contractions in by ifenprodil tartrate was significantly enhanced by the coadministration of calcium hopantenate. Ifenprodil tartrate caused dose-related relaxation of K+-induced contractions in isolated canine basilar arteries, while calcium hopantenate had no effect. The dose-relaxation curve of ifenprodil tartrate was shifted to the left by pre-incubation in calcium hopantenate. In K+-depolarized basilar arteries, ifenprodil competitively antagonized the response to Ca2+, and this was enhanced by pre-incubation in calcium hopantenate. Ifenprodil tartrate inhibited K+-induced Ca2+ uptake in canine cerebral arteries and this was enhanced by pre-incubation in calcium hopantenate. These results suggest that the enhancement by calcium hopantenate of the ifenprodil tartrate effect on the vertebral blood flow is due to increased vascular relaxation through the inhibition of Ca2+ influx.

Animals↗

Effects of ifenprodil tartrate on vertebral, basilar and internal carotid arteries.

Changes in blood flow of vertebral and internal carotid arteries of rats after the administration of ifenprodil tartrate were measured using the transit-time ultrasonic volume flowmeter. Tension of isolated canine basilar and internal carotid arteries was also tested isometrically. Ifenprodil tartrate produced a sustained increase in both vertebral and internal carotid arterial blood flow of rat. The increase in blood flow was greater in vertebral than in internal carotid arteries. Papaverine hydrochloride transiently increased arterial blood flow in both the vertebral and internal carotid arteries to approximately the same extent. Ifenprodil tartrate induced dose-related relaxation in basilar and in internal carotid arteries contracted with K+ (50 mM), and its effects were greater in basilar than in internal carotid arteries, while relaxation induced by papaverine hydrochloride was about the same in both arteries. These results suggest that the significant increase of vertebral arterial blood flow induced by ifenprodil tartrate is due to the peculiarity of vascular myorelaxation by this drug.

Animals↗