Biomedical subjects

S Kimoto-Kinoshita

Publications and source records attributed to S Kimoto-Kinoshita.

3 recordsLinked to original sources

PubMed2000

Decrease of endothelial nitric oxide synthase in stroke-prone spontaneously hypertensive rat cerebral cortex.

We reported in our previous study that constitutive nitric oxide synthase (cNOS) activity significantly decreased and oxygen stress increased in the 31-week-old stroke-prone spontaneously hypertensive rat (SHRSP) cerebral cortex (CC). In the present study we examined the protein amount of two cNOS isoforms, the neuronal and the endothelial types, in SHRSP CC using Western blot analysis. Although no significant difference was observed in the amount of neuronal NOS (nNOS) protein, endothelial NOS (eNOS) protein prominently decreased in 31-week-old SHRSP CC compared to age-matched Wistar Kyoto rat and 15-week-old SHRSP. In rats at this age, we also observed a large quantity of albumin in the protein amount. However, the protein amount of heat shock protein 70, which is a molecular chaperon and a marker of injury, showed no significant changes. These results indicate that the alteration of eNOS but not of nNOS protein would be more closely associated with the development of stroke in SHRSP.

Animals↗

PubMed2000

Type IV collagenase and immunostaining of type IV collagen in human thyroid tumors.

OBJECTIVE: Required stages in the processes of malignant tumor invasion and metastasis are known to include the destruction of cell stroma and vascular basement membrane. It has been suggested that type IV collagenase can degrade type IV collagen, a main component of basement membrane. In our study, type IV collagenase activity was compared with the grade of destruction of type IV collagen by thyroid tumors. METHODS: Type IV collagenase activity was measured in human thyroid tissue obtained surgically from four patients with Graves' disease, four with follicular adenoma, six with papillary carcinoma, and four with follicular carcinoma. Six normal thyroid tissue specimens were also studied. The grade of destruction in the diseased regions of thyroid tumors and surrounding intact tissues were determined immunochemically by anti-type IV collagen antibody staining. RESULTS: Tumors with high type IV collagenase activity exhibited extracapsular invasion, lymph node metastasis and very weak discontinuity of immunostaining for type IV collagen from the basement membrane in diseased regions. In addition, surrounding intact tissues exhibited weak immunostaining for type IV collagen. Tumors with low type IV collagenase activity exhibited neither extracapsular invasion nor lymph node metastasis, but did exhibit weak immunostaining for type IV collagen from the basement membranes in diseased regions. However, the surrounding intact tissues had preserved type IV collagen in follicular basement membranes. CONCLUSION: These findings suggest that staining for type IV collagen can be considered a biochemical marker for prediction of the aggressiveness of invasion and metastasis.

Adenoma↗

PubMed1999

Age-related change of antioxidant capacities in the cerebral cortex and hippocampus of stroke-prone spontaneously hypertensive rats.

Regional distribution and age-related change of Mn-, Cu/Zn-superoxide dismutase (SOD) and constitutive type of nitric oxide synthase (NOS) activities in the brain were determined using stroke-prone spontaneously hypertensive rats (SHRSP). In the hippocampus (HIP), Mn- and Cu/Zn-SOD activities in SHRSP of 31-week-old were significantly lower than those of 15-week-old or normotensive rats (WKY). From Mn-SOD immunohistochemical staining of several subfields of the HIP, our results suggested that SHRSP hippocampal CA1 was more vulnerable to oxidative stress compared with WKY and other subfields. In the 31-week-old SHRSP cerebral cortex (CC), the activities of Mn-, Cu/Zn-SOD and NOS were significantly lower than those in WKY. At this age, most of the SHRSP developed cerebral injuries. These observations indicated that hypertensive vascular disease observed in the SHRSP CC resulted from the decreased antioxidant capacity that is closely associated with the development of stroke and, in turn, shortened life span.

Aging↗