Biomedical subjects

T Takada

Publications and source records attributed to T Takada.

At least 199 records · Page 11Linked to original sources

PubMed1992

Gastrointestinal examinations with digital radiography.

Basic imaging properties and clinical usefulness of an upgraded digital radiography system were evaluated. The system, which has 1,024 x 1,024 and 2,048 x 2,048 matrices, was upgraded with smaller focal spots (0.3 and 0.8 mm) and reduced thickness of the photoconductive layer of the video camera. Screen-film and digital images (with and without postprocessing) of the upper and lower gastrointestinal (GI) tract were used in the clinical evaluation. Overall modulation transfer functions of the upgraded digital system were comparable to those of the screen-film system, especially at the lower spatial frequency. Threshold contrasts of the two systems were similar despite a 50% reduction in incident exposure for the digital system. For the upper GI tract, digital images processed with unsharp masking techniques were comparable in quality to screen-film images before and after upgrade of the system. For the lower GI tract, screen-film images were better than digital images, except for those produced with a 2,048 x 2,048 matrix with unsharp masking. Further evaluation of the system for examination of other parts of the body seems warranted.

Digestive System↗

PubMed1992

Detection of subtle microcalcifications: comparison of computed radiography and screen-film mammography.

Observer performance tests were conducted to compare the effects of image-processing technique (unsharp mask filtering) on the diagnostic accuracy of computed radiography (CR) with storage phosphors in the detection of microcalcifications. Comparison of detectability of microcalcifications with CR and with screen-film mammography was also performed. Clusters of microcalcifications (125-250 microns in diameter) were randomly superimposed on human breast specimens. Observer performance tests were carried out with receiver operating characteristic (ROC) analysis. The area under the ROC curve and the cumulative true-positive-localization fraction were both used as indexes of performance. Observer performance experiments with nine observers indicated that the two types of screen-film images used provided higher detectability than the CR images. The detectability of microcalcifications on the CR images improved slightly with use of the unsharp masking technique. However, no statistically significant difference was found between processed and unprocessed CR images, and detectability still did not reach the level achieved with the screen-film images.

Breast Diseases↗

PubMed1992

Effects of prorenin on blood pressure and plasma renin concentrations in stroke-prone spontaneously hypertensive rats.

To examine the possible activation of prorenin in the circulation, recombinant rat prorenin was intravenously given to pentobarbital-anesthetized rats. Bolus injection of prorenin at the dose of 100 micrograms angiotensin I (ANG I).h-1.kg-1 into Wistar rats, leading to a 15-fold increase in plasma prorenin concentrations (from 27 +/- 6 to 393 +/- 75 ng ANG I.h-1.ml-1) at 5 min after the injection, did not affect blood pressure, heart rate, and plasma active renin concentrations throughout experiments. On the other hand, the administration of active renin at the dose of 1, 3, and 10 micrograms ANG I.h-1.kg-1 increased mean blood pressure of Wistar rats by 8 +/- 2, 15 +/- 2, and 27 +/- 4 mmHg, respectively. Similar results were obtained in Wistar rats at 18 h after bilateral nephrectomy. These results confirmed no activation of prorenin in the circulation of normotensive rats. The activation of prorenin was also examined on both stroke-prone spontaneously hypertensive rats (SHRSP) and 18 h-nephrectomized SHRSP. There was no rise in blood pressure or plasma active renin concentrations in both groups of SHRSP after injection of prorenin. Thus the elevated plasma active renin in SHRSP [Shibota, M., A. Nagaoka, A. Shino, and T. Fujita. Am. J. Physiol. 236 (Heart Circ. Physiol. 5): H409-H416, 1979] seems to be caused by the enhanced release of active renin from the kidney rather than the activation of circulating prorenin.

Animals↗

PubMed1992

Effects of vitamin B12-deficiency on testes tissue in rats.

The state of vitamin B12-deficiency in rats was evaluated by determination of hepatic vitamin B12-dependent enzyme activities after the animals had fed on a vitamin B12-deficient soybean protein diet for 150 days. The effect of vitamin B12-deficiency on testicular tissue was also studied by morphological observations. Growth of vitamin B12-deficient rats was retarded and marked increase in urinary methylmalonic acid was observed. Vitamin B12 contents in the organs were depressed distinctly by the deficiency, especially in testes, vitamin B12 content decreased to 2.5 ng/g. Hepatic methionine synthase and methylmalonyl-CoA mutase activities showed striking depression to 5% of the control rats and extreme vitamin B12-deficiency was confirmed. Testes weight also showed marked decrease together with their relative weight per 100 g body weight. Morphological observations of testes of vitamin B12-deficient rats revealed atrophy of the seminiferous tubules and aplasia of sperms and spermatids. The above results proved that vitamin B12-deficiency affected rat testes, and suggested that the rat could be the animal model for elucidation of the mechanism of B12 action on testicular functions.

Animals↗

PubMed1992

Ultrastructural localization of Na+, K(+)-ATPase in the exorbital lacrimal gland of rat.

Ultrastructural localization of Na+, K(+)-ATPase in the exorbital lacrimal gland of rat was investigated quantitatively by protein A-gold technique. Na+, K(+)-ATPase was purified from the rat kidney, and anti-holo Na+, K(+)-ATPase antibody was obtained from the rabbit by injecting the purified enzyme. A specific antibody against the alpha-subunit of Na+, K(+)-ATPase was affinity purified. Immunoblot analysis revealed that the antibody bound specifically to the alpha-subunit of Na+, K(+)-ATPase of the lacrimal gland. Rats were fixed by perfusion with 4% paraformaldehyde containing 1% glutaraldehyde, and the lacrimal glands were embedded in LR White resin. Ultrathin sections were incubated with affinity purified antibody against the alpha-subunit of Na+, K(+)-ATPase, and then with protein A-gold complex. The sections were observed under an electron microscope. Light microscopy with silver enhancement procedure revealed that Na+, K(+)-ATPase was located mainly on the basal region of the cells of intralobular and interlobular ducts. Quantitative immunoelectron microscopic analysis showed that gold particles were found on the basolateral surfaces of the interlobular and intralobular ducts cells and on the basolateral surface of the acinar cells, whereas no significant binding was observed on any part of the apical surfaces of these cells. Labeling density of gold particles was highest on the basolateral surface of the interlobular duct cells, secondarily highest on the basolateral surface of the intralobular duct cells, and lowest on the basolateral surface of the acinar cells. The distribution pattern of Na+, K(+)-ATPase in the acinar cells and the duct cells suggest that this enzyme may play an important role in primary secretion and in determining the composition of electrolytes in the final secretion, respectively.

Animals↗

PubMed1992

[An assessment of the separation of mediastinal lymph nodes by preoperative mediastinoscopic examination as a dissecting measure in the surgical treatment of lung cancer].

The availability of the separation of mediastinal lymph nodes by preoperative mediastinoscopic examination as a dissecting measure was analyzed according to prognosis retrospectively because mediastinal lymph nodes dissection is made with ease and certainty after the examination. The separation by mediastinoscopic examination did not have an impact on the mediastinal lymph nodes dissection for carcinoma of the left lung and superior mediastinal lymph nodes metastases (# 1-4), but an influence on the dissection for carcinoma of the right lung and middle and lower mediastinal lymph nodes metastases (# 5-9). This result showed the existence of occult metastases and the good effects caused by the separation of mediastinal lymph nodes. In the histological type, the effects were present in squamous cell carcinoma and p-N0 adenocarcinoma, but it was concluded that the prognosis in adenocarcinoma was associated with other factors rather than lymph node metastasis. Therefore, it can be seen that the separation of mediastinal lymph nodes by preoperative mediastinoscopic examination is available as a dissecting measure.

Adult↗

PubMed1992

Relationship of cholecystectomy and detachment of the common bile duct to chronic bile duct dilation.

A combination of a cholecystectomy and detachment of the supportive tissue surrounding the extrahepatic bile duct results in chronic bile duct dilation. To clarify whether this cholangiectasis is due to the detachment of the surrounding tissue or to the cholecystectomy, we have studied 4 groups of adult mongrel dogs, i.e., a control group given a sham operation (n = 20), a group given cholecystectomy (n = 20), a group that had the surrounding tissue detached from the bile duct (n = 20), and a group given both a cholecystectomy and detachment of the surrounding tissue (n = 29). On examination by cholangiography at 1, 2, 3, and 4 weeks after the initial laparotomy, no significant cholangiectasis was found in dogs subjected to either cholecystectomy alone or to detachment of the surrounding tissue alone. In contrast, in dogs subjected to a cholecystectomy combined with detachment of the bile duct, the bile duct gradually dilated, resulting in significant cholangiectasis at 4 weeks. However, the intrabiliary pressure, the residual pressure, and the actual resistance value, which are indices of a passage disturbance in the sphincter of Oddi, were normal in all 4 groups. It is therefore concluded that both the extirpation of the gallbladder, and the lack of supportive tissue surrounding the bile duct were responsible for the resulting cholangiectasis.

Animals↗

PubMed1992

[Investigation on central venous catheter related sepsis].

We made an investigation on central venous catheter related sepsis (CRS) in recent 5 years (1987-1991). The incidence of CRS was high; 16.0% (125 out of 782 cases) or 13.1% (135 out of 1029 catheters). CRS occurred frequently during 2-3 weeks after catheter insertion. The incidence of CRS was not affected by the kind of disease (malignant or benign), complication (diabetes, liver cirrhosis, collagen disease) operation or administration of antibiotics. Eight percent out of 91 organisms isolated from culture of catheter tips were so-called resistant strains; multi-drug resistant Staphylococci (16), Pseudomonas aeruginosa (5), fungi (49), etc. Complications (shock, acute renal failure, secondary pneumonia, fungal endophthalmitis) broken out in 18 patients (14.4% out of 125 CRS). Fungi were isolated from 14 out of 18 complicated cases, furthermore fungi were isolated alone in 11 cases. No complication were seen among cases from which gram positive cocci were isolated alone. Body temperature and white blood cell count of complicated cases were significantly higher than those of uncomplicated cases. The duration until removal of catheter from outbreak of fever in complicated cases was significantly longer than that in uncomplicated cases.

Candida↗

PubMed1992

[Effects of intravenously infused magnesium on renal calcium metabolism and plasma parathyroid hormone in patients with essential hypertension].

This study aimed to elucidate the effects of intravenously infused magnesium on renal calcium and sodium metabolism in patients with essential hypertension. Mean arterial pressure (MAP), heart rate (HR), urine volume (UV), endogenous creatinine clearance (Ccr), urinary excretion of calcium (UCaV) and sodium (UNaV), fractional excretion of calcium (FECa) and sodium (FENa), plasma ionized calcium (pCa2+) and parathyroid hormone(PTH) were measured before and after intravenous infusion of 10% magnesium sulfate (initial dose: Mg 13.5mg/m2.BSA/15 min.: maintenance dose: Mg 2.7mg/m2.BSA/105min) in 6 normotensive subjects (NT) and 13 mild-to-moderate essential hypertensives (EHT). After the magnesium infusion, significant increases of UV, UCaV, UNaV, FECa and FENa, and a significant decrease of PTH were observed in both NT and EHT while MAP and HR did not change in either group. PCa2+ significantly decreased and Ccr tended to increase only in EHT. Although no significant difference was found in the change in Ccr (delta Ccr) or PTH (delta PTH) between NT and EHT, the changes of UCaV (delta UCaV), UNaV (delta UNaV), FECa (delta FECa) and FENa (delta FENa) were greater in EHT than each in NT. A positive correlation was found between delta UCaV and delta FECa, as well as delta UCaV and delta Ccr, but the former was more remarkable in both groups. In addition, delta UCaV was positively correlated with delta FENa in EHT, but not in NT. No significant relationship was observed between delta UCaV and delta PTH in either group.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium↗

PubMed1992

[Prospective randomized trial comparing modified FAM (5-fluorouracil (5-FU) + adriamycin + mitomycin C) versus 5-FU alone for the treatment of non-resectable pancreatic and biliary tract carcinomas (the 1st trial in non-resectable patients). Study Group of Surgical Adjuvant Therapy for Carcinomas of the Pancreas and Biliary Tract].

The modified FAM (5-fluorouracil (5-FU) + adriamycin (ADR) + mitomycin C (MMC)) therapy (FAM group) was compared with 5-FU mono-therapy (F group) by multi-institutional randomized trial in the patients with cancer of the pancreas or the biliary tract who underwent non-resection. The patients in FAM group received 6 mg/m2 of i.v. MMC during operation, 310 mg/m2 of i.v. 5-FU for 5 days in the 1st and 3rd postoperative weeks and 12 mg/m2 of i.v. ADR in the 2nd postoperative week. Those in F group received only 5-FU course in the administration schedule of FAM group. Among the cases which completed respective whole administration schedules. 35 cases in FAM group and 36 in F group, better effect than partial response (PR) was observed in neither groups, and there was no significant difference between groups with respect to overall/each disease survival duration, progression-suppressed duration and clinical effect. Primary adverse effects were alimentary symptoms and hepatic dysfunction, neither of which was serious, and there was no difference between groups except that hair loss was observed in more cases in FAM group (p less than 0.05). Results in FAM group did not statistically surpass those in F group, but a tendency was observed that FAM group was better than F group in terms of survival duration and clinical effect for cancer of the gall-bladder.

Adult↗

PubMed1992

[An attempt at intraoperative, ultrasound-guided microwave tissue coagulation for metastatic liver tumors].

Using a microwave tissue coagulator, we attempted intraoperative, ultrasound-guided cauterization and thermocoagulation of metastatic liver tumors. The procedure, safety and efficacy of this therapy were analyzed. During the past 2 years, this therapy was used in 10 patients with unresectable metastatic liver tumors. During surgery, monopolar electrodes were inserted with an ultrasonic guide. One round of cauterization lasted for 10 seconds at 100 W. It was repeated until the tissue around the tumor became hyperechoic. This therapy was used for 67 tumor lesions in total (2-22 lesions/patient). No complications were observed during or after this therapy, except for a case complicated by liver abscess. The anti-tumor effect of the therapy was assessed by histological examination of resected liver tissues. Tumor coagulation and necrosis were observed consistent with the cauterized area. The response to this therapy, assessed by diagnostic imaging, was CR (complete remission) in 3 cases, PR (partial remission) in 3, NC (no change) in 3 and PD (progressive disease) in 1. Thus, the efficacy (the percentage of cases showing CR or PR) was 60%. Since this therapeutic approach acts directly on tumors and is simple and safe, it seems to provide a useful means for intraoperative regional treatment of tumors.

Adult↗

PubMed1991

[The role of the renal dopaminergic and the prostaglandin systems in renal uric acid metabolism in patients with essential hypertension].

The present study aimed to elucidate the role of renal dopaminergic and prostaglandin (PG) systems in renal uric acid metabolism in essential hypertension. Mean arterial pressure (MAP), heart rate (HR), endogenous creatinine clearance (Ccr), serum uric acid (SUA), urinary excretions of uric acid (UUAV) and sodium (UNaV), fractional excretions of uric acid (FEUA) and sodium (FENa), plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were measured before and after intravenous injection of a dopamine receptor antagonist, metoclopramide (MCP: 8 mg/m2.BSA), or before and after a single oral administration of prostaglandin synthesis inhibitor, indomethacin (IM: 75 mg), in 34 mild-to-moderate essential hypertensives (EHT). MCP injection or acute oral administration of IM caused significant decreases of UNaV and FENa in each group, whereas MAP, HR and SUA did not change in either group. Significant decreases in Ccr, UUAV and FEUA and increases in PRA and PAC were demonstrated by MCP injection, while no significant changes in these parameters were revealed by IM administration. There was a significant positive correlation between delta UUAV and delta Ccr or delta FEUA in both groups. In addition, a close positive correlation between delta UUAV and delta UNaV as well as between delta FEUA and delta FENa was found in the MCP group, but not in the IM group. On the other hand, no significant correlation was observed between delta UUAV and delta PRA or delta PAC in either MCP or IM administration. The decreases of UUAV and FEUA were significantly greater in MCP than in IM administration, despite similar changes in Ccr, UNaV and FENa between the two procedures. These data suggest that the endogenous renal dopaminergic system may contribute to renal uric acid metabolism, which is rather closely related to sodium handling in essential hypertension than the prostaglandin system. Furthermore, the attenuated renal dopaminergic activity may contribute to the elevation of serum uric acid level in patients with essential hypertension.

Adult↗

PubMed1991

[The role of hyperinsulinemia on the renal mechanism of hyperuricemia in overweight patients with essential hypertension].

The aim of the present study was to investigate the role of insulin on the renal mechanism of hyperuricemia in overweight patients with essential hypertension. Thirty-four essential hypertensives(EHT), receiving a regular diet containing 120mEq of sodium, 75mEq of potassium and 2000 kilocalories daily, were divided into two groups of non-obese(NHT) and obese(OHT) EHT. NHT as categorized as a body mass index (BMI) less than, and OHT as a BMI equal to or more than, 25 kg/m2 in male patients and 24 kg/m2 in female patients. In the early morning after overnight fast, renal uric acid and sodium clearance were examined while the patients remained in a supine position. During the two-hour clearance period, mean arterial pressure(MAP), heart rate(HR), endogenous creatinine clearance(Ccr), immunoreactive insulin(IRI), serum uric acid(SUA), fractional excretion of uric acid(FEUA) and sodium(FENa) were measured. Although there were no significant differences in age, MAP, HR, Ccr, nor SUA between the two groups, a higher ratio of female to male patients was found in OHT than in NHT. On the other hand, higher SUA and IRI and lower FEUA and FENa were observed in OHT than in sex-and Ccr-matched NHT. SUA was negatively correlated with FEUA in all patients (r = -0.392, p less than 0.05) and in NHT (r = -0.553, p less than 0.05), unlike in OHT. A significant negative correlation between BMI and FEUA was revealed in all EHT (r = -0.441, p less than 0.01) and in OHT (r = -0.597, p less than 0.01) but not in NHT. FEUA was positively correlated with FENa in all EHT (r = 0.554, p less than 0.001) as well as in NHT (r = 0.548, p less than 0.05) and OHT (r = 0.507, p less than 0.05). Moreover, there was a significant negative correlation between IRI and FENa in all EHT (r = -0.361, P less than 0.05) and in OHT (r = -0.470, p less than 0.05). However, no significant relation was demonstrated between IRI and SUA or FEUA in NHT or OHT. From these results, it is concluded that an attenuated renal excretion of uric acid related to natriuretic ability may play an important role in hyperuricemia in EHT. However, the role of hyperinsulinemia, which contributes to the blunting of natriuresis, might be relatively small in the renal mechanism of hyperuricemia in EHT, particularly in OHT.

Female↗

PubMed1991

Increased production of angiotensin II in the adrenal gland of stroke-prone spontaneously hypertensive rats with malignant hypertension.

Angiotensin(Ang) contents in the adrenal gland of stroke-prone spontaneously hypertensive rats(SHRSP) and age-matched Wistar Kyoto rats(WKY) were determined using reverse phase high performance liquid chromatography combined with a specific radioimmunoassay. In normotensive 5 wk-old SHRSP, the adrenal renin activity was about 3 times higher than that of age-matched WKY while the adrenal Ang I and Ang II concentrations did not differ from those of WKY. In the severely hypertensive 25 wk-old SHRSP, the adrenal Ang II and Ang I, and plasma aldosterone concentrations were about 5-fold, 2-fold and 4-fold, respectively, increased compared with levels in the WKY. In the 25 wk-old SHRSP 24 h after bilateral nephrectomy, the adrenal Ang II and plasma aldosterone levels were not decreased and were 10 and 3 times, respectively, higher than those of nephrectomized control WKY. Thus, the enhanced local generation of Ang II in the adrenal gland may contribute to the increased release of aldosterone in SHRSP with malignant hypertension.

Adrenal Glands↗

PubMed1991

The dynamical attainability of ESS in evolutionary games.

In this paper, the attainability of ESS of the evolutionary game among n players under the frequency-independent selection is studied by means of a mathematical model describing the dynamical development and a concept of stability (strongly determined stability). It is assumed that natural selection and small mutations cause the phenotype to change gradually in the direction of fitness increasing. It is shown that (1) the ESS solution is not always evolutionarily attainable in the evolutionary dynamics, (2) in the game where the interaction between two species is completely competitive, the Nash solution is always attainable, and (3) one of two species may attain the state of minimum fitness as a result of evolution. The attainability of ESS is also examined in two game models on the sex ratio of wasps and aphids in light of our criterion of the attainability of ESS.

Animals↗

PubMed1991

Choledochoscopy during biliary surgery for reducing the risk of overlooked stones.

Although cholangiography is routinely performed during biliary surgery to ensure the removal of all stones, it is not always successful. Some investigators have claimed that intraoperative choledochoscopy is more effective in detecting all stones, although reports on the efficacy of this method have been contradictory. Furthermore, no study has systematically examined either of these procedures in terms of the actual incidence of overlooked stones. Thus, to evaluate the merits of intraoperative cholangiography as opposed to choledochoscopy, we studied the incidence of overlooked bile duct stones after surgery. We investigated 126 patients who had undergone surgery during which choledocholithotomy was performed within the past 10 years; 117 of these cases involved common bile duct stones and 22, intrahepatic stones. After the exclusion of 13 subjects whose stones were deliberately left for postoperative treatment due to severe complications, 126 patients were finally analyzed. Overlooked stones were found postoperatively in 13 (10%) of these 126 subjects, including 11 (14%) of 63 patients who had been inspected by intraoperative cholangiography alone and 2 (3%) of 63 who had undergone both choledochoscopy and cholangiography during surgery. Therefore, the incidence of overlooked stones proved to be significantly lower in those who had undergone choledochoscopy combined with cholangiography (P less than 0.01). Our results suggest the value of combining choledochoscopy with cholangiography during surgery for reducing the risk of overlooked bile duct stones.

Bile Duct Diseases↗

PubMed1991

SD-3211, a novel benzothiazine calcium antagonist, alone and in combination with a beta-adrenoceptor antagonist, produces antihypertensive effects without affecting heart rate and atrioventricular conduction in conscious renal hypertensive dogs.

We compared the effects of SD-3211, a novel calcium antagonist, on blood pressure, heart rate, and atrioventricular conduction with those of diltiazem using conscious renal hypertensive dogs (one-kidney, one-clip type). We also examined the combined effects of these calcium antagonists with a beta-adrenoceptor antagonist, propranolol, on these variables. Oral administration of SD-3211 (1.25, 2.5, and 5 mg/kg) resulted in a dose-dependent decrease in blood pressure without affecting heart rate. SD-3211 at all three doses significantly decreased systolic blood pressure. At 2.5 and 5 mg/kg the compound elicited significant decreases in mean blood pressure and diastolic blood pressure. Hypotension obtained with the highest dose of SD-3211 lasted for at least 9 h. No significant alteration in PR interval was observed in electrocardiograms after administration of SD-3211. Diltiazem, given orally at doses of 2.5 and 5 mg/kg but not 1.25 mg/kg, produced significant hypotension with little change in heart rate. The duration of hypotension induced by the highest dose of diltiazem was only 3 h. Diltiazem prolonged PR interval in a dose-dependent manner, causing second-degree atrioventricular block in some dogs. Combined administration of SD-3211 or diltiazem (2.5 mg/kg) with propranolol (30 mg/kg) resulted in enhanced hypotension with no alteration in heart rate. SD-3211 plus propranolol had little effect on the PR interval, whereas diltiazem plus propranolol caused a markedly enhanced prolongation. These results indicate that SD-3211 is an antihypertensive agent with long-lasting action and little effect on heart rate and atrioventricular conduction and, when administered alone or in combination with propranolol, may be useful in the treatment of hypertension.

Administration, Oral↗

PubMed1991

Antihypertensive effect of a novel calcium antagonist, SD-3211, in experimental hypertensive rats.

The antihypertensive effect of SD-3211, a structurally novel type of nondihydropyridine calcium antagonist, was assessed using several types of experimental hypertensive rats. Oral administration of SD-3211 (10, 20, and 30 mg/kg) to conscious spontaneously hypertensive rats (SHR), deoxycorticosterone acetate-salt hypertensive rats (DHR) and 2-kidney, 1-clip renal hypertensive rats (RHR) resulted in a dose-dependent decrease in systolic blood pressure (SBP). The hypotensive effect of SD-3211 in these hypertensive rats was more pronounced than in normotensive rats (NR). The potencies of SD-3211 for the hypotensive effect in the hypertensive rats and NR were 5-7 times greater than that of diltiazem but 2-3 times less than that of nicardipine. Furthermore, SD-3211 showed longer-lasting hypotensive action than diltiazem and nicardipine, at the respective equihypotensive dose. During the course of hypotension, SD-3211 did not exert any influence on heart rate (HR) in any type of hypertensive rats or NR, in contrast to the appearance of tachycardia with nicardipine in SHR, DHR, and NR and of bradycardia with diltiazem in DHR. At doses of 10 and 30 mg/kg, the hypotensive doses, SD-3211 elicited a dose-dependent natriuresis but no kaliuresis in SHR. In the chronic study using SHR, SD-3211 at 10 mg/kg/day showed an antihypertensive effect during an administration period of 12 consecutive weeks. These results allow us to conclude that SD-3211 has a potent and long-lasting hypotensive action with little cardiac effect.

Animals↗