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N Ohno

Publications and source records attributed to N Ohno.

291 records · Page 17Linked to original sources

Cytochemical detection of endogenous peroxidase in the acinar cells of the hamster submandibular gland.

The presence of endogenous peroxidase activity in the hamster submandibular gland was investigated cytochemically by light and electron microscopy using diaminobenzidine methods. After fixation of tissue with 2% paraformaldehyde-2.5% glutaraldehyde and incubation in a DAB reaction medium containing 0.01% H2O2, the peroxidase reaction product was localized in the nuclear envelope, the cisternae of the endoplasmic reticulum, secretory granules and the Golgi apparatus in both the acinar and granular duct cells of the submandibular gland. This is in contrast to earlier investigators who failed to detect peroxidase activity in acinar cells of the hamster submandibular gland and reported that peroxidase is localized only in the granular duct cells. The discrepancy may be caused by differences in experimental procedures. It is suggested that fixation of tissue with a high concentration of glutaraldehyde and incubation in a DAB reaction medium containing a high concentration of H2O2 inhibits the peroxidase activity of acinar cells in the hamster submandibular gland.

3,3'-Diaminobenzidine↗

Pharmacodynamic effects of chronic cigarette smoke exposure in spontaneously hypertensive rats.

In investigating the influence of chronic cigarette smoke exposure on hypertension, we compared the pharmacodynamic effects of enforced exposure to smoke on spontaneously hypertensive rats (SHR) with those on Wistar-Kyoto (WKY) rats. Chronic cigarette smoke exposure for 8 weeks decreased the elevated heart rate of mature male SHR to approximately the rate in WKY rats 24 h after smoke exposure. Both systolic and diastolic blood pressures also decreased slightly. However, WKY rats showed a marked rise in heart rate soon after exposure to cigarette smoke began, with no change in blood pressure, while the heart rate of SHR in the early stage remained similar to that of animals without exposure, although their blood pressure was clearly reduced. The body weight of both strains tended to decrease during smoke exposure, but the effect was more severe in SHR. Moreover, the effects of chronic smoke exposure were observed using retired, aged female SHR breeders. A decrease in body weight and heart rate, but not in blood pressure, was also recognized even in these mature animals. These effects gradually recovered after withdrawal from exposure. On the basis of these results, a profile of chronic cigarette smoke exposure under hypertension is discussed in this study.

Aging↗