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Biomedical subjects

Y Tajima

Publications and source records attributed to Y Tajima.

At least 235 records · Page 13Linked to original sources
PubMed1984

Hemodynamic effects of captopril in one-kidney, one clip hypertensive rabbits.

Hemodynamic effects of captopril were examined in chronic one-kidney, one clip renal hypertensive rabbits and normotensive controls either in normal sodium or in sodium depletion. The mean arterial pressure (MAP) of hypertensive and normotensive rabbits in sodium depletion did not differ from that in normal sodium, while plasma renin activity (PRA) was elevated by sodium depletion. The cardiac output of sodium depleted groups decreased slightly. The increase in total peripheral resistance was greater in hypertensive than in normotensive groups. The MAP in all groups was decreased by acute administration of captopril irrespective of sodium intake. The decrease in MAP in the sodium-depleted hypertensive group was correlated with the control values of PRA, but no correlation was observed in other groups. Captopril significantly reduced the cardiac output of the sodium-depleted hypertensive group, but not of the other groups. These results show that: (1) the lowering effect of captopril on arterial pressure is not mediated only by blocking of the renin-angiotensin system, and (2) the decrease in cardiac output with captopril in sodium depleted hypertensive rabbits is an important factor in the reduction in the arterial pressure.

Animals↗
PubMed1984

[Glucagonoma].

A 36 year old woman was admitted because of upper abdominal pain, fullness and weight loss. Pancreatic scintigram revealed abnormal accumulation of the radioisotope in the pancreatic head, and hepatic scintigram showed multiple filling defect in the bilateral lobe. Celiac angiogram demonstrated a tumor stain at the pancreatic head, encasement of the splenic artery and metastasis to the liver. The diagnosis of malignant glucagonoma was substantiated by high serum glucagon level of 1,100 pg/ml. Streptozotocin of 1.5g was administered intravenously once a week, totalling 9g. Thereafter, blood level of glucagon declined to the normal range, accompanied by improvement of diabetes mellitus and weight gain. At laparotomy, there was an over fist-sized mass at the body and tail of the pancreas, infiltrating the pancreatic head and periaortic region, and was found unresectable. On light microscopy, biopsied specimen was seen to be a tumor that contained glucagon. Secretary granules resembling A cell granules were observed by electron microscopy. She died of emaciation 6 years after the onset of the disease. Eighteen cases of glucagonoma reported in Japan, and 64 cases in Europe and the United States were reviewed in terms of the diagnosis and treatment.

Adenoma, Islet Cell↗
PubMed1983

X-ray structure analysis of thin filaments of a molluscan smooth muscle in the living relaxed state.

In the small-angle x-ray diffraction pattern of the living relaxed anterior byssus retractor muscle of Mytilus edulis, the thin filaments showed the following features. The 59.8-A reflection was much stronger and a little farther from the meridian than the 51.9-A reflection, although they are both contributions of the first-order Bessel function and are comparable with each other in the height from the equator. The 381-A reflection, given by the second-order Bessel function, was weaker than the 59.8-A reflection by more than the difference between the peak values of the first- and second-order Bessel functions, and was not so distant radially from the latter as estimated from the amount of peak shift brought about by the alteration of the Bessel order. A model of the thin filament was made on the basis of inverse Fourier transformation of the scattering amplitude, and the above features were explained by the characteristic shape of actin shown in this model. The actin subunits are elongated along the genetic left-hand helix with a pitch of 59.8 A, and are bonded together along the genetic helix in the inner part of the filament.

Animals↗
PubMed1983

Body fluid distribution in the maintenance of DOCA-salt hypertension in rats.

Body fluid volumes and their relation to mean arterial pressure and plasma renin activity (PRA) were examined in heminephrectomized rats after 4 wk of treatment with deoxy-corticosterone acetate (DOCA) and placed on one of three levels of salt intake, either high (D-HS), normal (D-NS), or low (D-LS); sham-operated rats, which received heminephrectomy and no DOCA treatment, also received high (S-HS), normal (S-NS), or low (S-LS) intakes of salt. Body fluid volumes were measured as the distribution volumes of radioiodinated serum albumin, 35SO4, and tritiated water for plasma volume (PV), extracellular fluid volume (EFV), and total body water (TBW), respectively. Approximately the same degrees of hypertension occurred in the D-HS and D-NS rats, but the D-LS rats were normotensive. PV and EFV were increased only in the D-HS rats, with no prominent changes occurring in the D-NS rats. Intracellular fluid volume (ICF) was not changed in the D-NS rats when compared with the S-NS rats. The ratios of PV/EFV and EFV/TBW in the DOCA-treated groups on high or normal salt were not different from their controls. PRA was greatly suppressed in the D-HS and D-NS rats when compared with all other groups. In another group of D-HS rats, sodium was restricted for 2 wk; in this group the mean arterial pressure fell to control levels without significant changes in PV, but interstitial fluid volume was reduced to normal levels. These results demonstrated that 1) in DOCA-salt hypertensive rats there is expansion of body fluid volumes that are proportionally distributed among the PV, EFV, and ICF; 2) increases in body fluid volumes are not necessary for DOCA to maintain hypertension; 3) a certain minimal amount of dietary sodium is necessary for the development and maintenance of hypertension; and 4) following DOCA treatment the suppression of PRA is not due solely to expansion of body fluid volumes.

Animals↗