Antihypertensive effect of bopindolol on stroke-prone spontaneously hypertensive rats (SHRSP)

The antihypertensive effect of bopindolol, a long-acting beta-adrenoceptor blocking agent, was investigated in stroke-prone spontaneously hypertensive rats (SHRSP). One group received tap water during the period of 8 to 32 weeks of age. The average dose of bopindolol administered was calculated from water intake to be approximately 1.4 mg/kg/day. The lowering effect in blood pressure of bopindolol was apparent at the age of 14 weeks, and this continued up to the end of the experiment. Bopindolol significantly reduced the heart rate. Plasma levels of urea nitrogen (BUN), triglyceride, and phospholipid of SHRSP treated with bopindolol were lower than those of the control SHRSP. One of the 8 control SHRSP died, and no rats treated with bopindolol died during the experiment. The histopathological study revealed that three of the control SHRSP had cerebral apoplexy, whereas there was no evidence of cerebral apoplexy in the treated SHRSP. Chronic treatment of bopindolol clearly alleviated myocardial fibrosis and hypertrophic changes in the left ventricular wall of the heart. Decreases in the incidence of proliferative arteritis and malignant nephrosclerosis in the kidney and necrotizing arteritis of the mesenteric arteries were observed in SHRSP treated with bopindolol. The data presented indicate that bopindolol is a powerful antihypertensive agent.     

The effect of methamphetamine on serotonin and its metabolite in the suprachiasmatic nucleus: A microdialysis study

Summary The suprachiasmatic nucleus (SCN) has been identified as a major circadian pacemaker. Methamphetamine has been shown to modify the behavior of circadian rhythms. We detected extracellular serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the SCN in freely moving rats, using a microdialysis method, to investigate biochemical effects of methamphetamine in the SCN. Methamphetamine infusion into the SCN dose-dependently increased extracellular 5-HT and decreased extracellular 5-HIAA.     

Body temperature monitoring in subjects with delayed sleep phase syndrome

To clarify the circadian aspects of delayed sleep phase syndrome (DSPS) in 4 patients with DSPS, we recorded polysomnograms and rectal temperature before and after chronotherapy. The time interval (2.7 h) between sleep onset and rectal temperature minimum before chronotherapy was shorter than the time interval after chronotherapy (5.3 h). Before chronotherapy, the period of rectal temperature rhythm was 24.7 h. After chronotherapy, the period of rectal temperature rhythm was 24.0 h. These findings lead to the conclusion that in DSPS there is a weakened mechanism of entrainment similar to that in non-24-hour sleep-wake syndrome.     

Enhanced clearance of lactic dehydrogenase-5 in severe combined immunodeficiency (SCID) mice: effect of lactic dehydrogenase virus on enzyme clearance.

The lactic dehydrogenase (LDH) level in plasma and the clearance of LDH in C.B-17 scid (severe combined immunodeficiency; SCID) mice were compared with those in C.B-17 or BALB/cCrSlc mice with or without lactic dehydrogenase virus (LDV) infection. The resting enzyme level in SCID mice showed little difference from that in C.B-17 or BALB/cCrSlc mice. The degree of increased plasma LDH level in SCID mice was lower than that in C.B-17 and BALB/cCrSlc mice after LDV infection. To assess the mechanisms of decrease in LDH elevation in SCID mice infected with LDV, virus replication was compared in SCID and BALB/cCrSlc mice. The infectivity titre of plasma in SCID mice was higher (more than 10 times) than that in BALB/cCrSlc mice. Moreover, the percentage of virus antigen positive Kupffer cells was higher in SCID mice than that in BALB/cCrSlc mice. The level of endogenous LDH release as a result of carbon tetrachloride treatment was similar in the SCID and BALB/cCrSlc mice. The clearance rate of endogenous LDH was greater in SCID mice than in BALB/cCrSlc mice with or without LDV infection. The rate of clearance of intravenously injected porcine LDH-5, but not porcine LDH-1, was enhanced in SCID mice as compared with that in BALB/cCrSlc mice. Furthermore, carbon clearance was higher in SCID mice than that in BALB/cCrSlc mice. These results suggest that the smaller increase of plasma LDH after infection might be due, at least in part, to the enhanced LDH-5 clearance function by macrophages in SCID mice.     

Surgical repair of discrete subaortic stenosis complicated with prosthetic valve endocarditis--a case report]

A 46-year-old man was referred to our hospital because of prosthetic valve regurgitation. Eight years previously he had undergone aortic valve replacement because of aortic regurgitation due to infective endocarditis. At reoperation, we found prosthetic valve endocarditis and discrete subaortic stenosis. The obstructing fibrous tissue was resected and the aortic valve was replaced. Because discrete subaortic stenosis is usually located just below the aortic valve, the aortic valve cusps are liable to become thickened by the jet through the discrete stenosis and thus are vulnerable to infective endocarditis. It is pointed out that care must be taken not to overlook discrete subaortic stenosis in the presence of other associated cardiac disorders.     

Measurement of free and total hydroxyproline by automated flow injection of serum or urine samples from maintenance hemodialysis patients with renal osteodystrophy

An automated measurement of total and free hydroxyproline in serum or urine is presented that uses flow injection analysis. After exclusion of nonspecific substances, hydroxyproline was oxidized by chloramine- T and L-cysteine with Ehrlich's reagent. The linearity obtained was from 3.8μmole/ L to 1.22 mmole/L with good precision (CV <3%). Comparison of the proposed method with HPLC yielded r = 0.939 as the correlation coefficient. Reference intervals of free and total hydroxyproline are 1.4–9.7 μmole/L, 3.8–27.2 μmole/L for serum, and 10.0–72.5 μmole/L, 25.2–303.6 μmole/L for urine, respectively. Serum free and total hydroxyproline levels in renal osteodystrophy patients on maintenance hemodialysis (N = 71) were significantly higher than in controls (P<0.0001). This method is superior to the use of HPLC with regard to stability of the color reaction. The measurement of serum free and total hydroxyproline is a useful marker for therapeutic observation of renal osteodystrophy patients. © 1994 Wiley-Liss, Inc.     

Tricuspid annuloplasty and right ventricular function in mitral valve disease

From 1985 to 1987, we examined relationship between the lesion of tricuspid valve and right ventricular function in 31 patients (male: 9, female: 22) with mitral valve disease. The median age at operation was 52 years (range 37-69 years). Group I consisted of 17 patients (MS: 10, MSR: 5, MR: 2) accompanied with tricuspid regurgitation (TR) and Group II 14 patients (MS: 12, MSR: 2) without TR. In all cases of Group I tricuspid annuloplasty (TAP) were performed correctly. De Vega methods were done in 12 cases and Carpentier rings were used in 5 cases. Cardiac catheterization was done before and after operation. And right ventricular volume was measured by right ventricular angiography. In both groups pulmonary capillary wedge pressure, pulmonary artery pressure and cardiac index were improved postoperatively. Pulmonary artery resistance (PAR) and total pulmonary resistance (TPR) in Group I were significantly higher before operation but there were no difference between two groups postoperatively. Right ventricular end-diastolic volume index (RVEDVI) and right ventricular end-systolic volume index (RVESVI) in Group I were significantly improved postoperatively, but in Group II these were within normal range both pre- and postoperatively. Preoperative PAR was correlated inversely with postoperative right ventricular ejection fraction (RVEF). It means that patients with severe pulmonary vascular lesion had postoperative lower right ventricular function. In both groups, RVESVI was in inverse correlation with RVEF pre- and postoperatively. In both groups, there was an inverse correlation between the per cent change of RVESVI and that of RVEF. This means that RVESVI influenced right ventricular pump function.     

Primary leiomyosarcoma of the thyroid gland

Primary leiomyosarcoma of the thyroid gland is extremely rare, and to the best of our knowledge only five well-documented cases have been reported in the world literature. We herein report a 58-year-old female patient with primary leiomyosarcoma of the thyroid who was successfully treated by total thyroidectomy with a modified neck dissection. Immunohistochemically, the tumor cells showed positive reactivity to α-smooth muscle actin and vimentin. Radical surgery was thus considered to be essential in the treatment of this rare but rather aggressive malignancy.     

Specific [125I]brain natriuretic peptide-26 binding sites in rat and pig kidneys

Specific binding sites for porcine brain natriuretic peptide-26 (BNP-26), a member of the atrial natriuretic peptide family (ANPs), were investigated in the kidney by using receptor autoradiographic and membrane binding techniques with [125I]BNP-26. The binding sites were discretely localized in rat and porcine kidney areas corresponding anatomically to the glomeruli and inner medulla. There were no differences between the localization of [125I]BNP-26 and [125I]alpha-rat ANP binding sites in the kidney. [125I]BNP-26 binding to solubilized membranes from isolated glomeruli of the rat kidney was saturable, and a single class of high-affinity sites was labeled with a KD of 372 pM. The radioligand bound to two sites in solubilized inner medullary membranes of the rat, a low-affinity site with a KD of 30 nM, and a high-affinity site with a KD of 33 pM. The rank order of potency to inhibit binding was BNP-26 = alpha-rat ANP-(1-28) greater than atriopeptin III (ANP-(103-126)) much greater than atriopeptin I (ANP-(103-123)) greater than des-Cys105,Cys121- ANP-(104-126). Thus, [125I]BNP-26 presumably recognizes ANP receptors in the kidney. The possibility that BNP-26 regulates, as a circulating hormone, kidney functions by binding to ANP receptors would have to be considered.