Danshen, a Chinese herb, reduces hypertension in Oriental medicine. We hypothesized that Danshen acts partially through endothelial nitric oxide synthase (eNOS) signaling mechanisms. We tested the hypothesis using tanshinone II(A), an active ingredient of Danshen, and the two-kidney, one-clip renovascular hypertension model in hamsters. Oral tanshinone (50 microg/100 g body wt) reduced mean art...

To assess the hypothesis that gap junctions (GJs) participate on leukocyte-endothelium interactions in the inflammatory response, we compared leukocyte adhesion and transmigration elicited by cytokine stimulation in the presence or absence of GJ blockers in the hamster cheek pouch and also in the cremaster muscle of wild-type (WT) and endothelium-specific connexin 43 (Cx43) null mice (Cx43e(-/-...

OBJECTIVE The first goal of this study was to determine the effect of diabetes mellitus on agonist-induced increases in venular macromolecular permeability of the hamster cheek pouch. The second goal was examine the role for an alteration in the availability of L-arginine to nitric oxide synthase in impaired agonist-induced increases in macromolecular permeability during diabetes. METHODS We ...

In order to investigate the involvement of cyclooxygenase (COX)-2 in oral carcinogenesis and chemoprevention for it, we examined the COX-2 expression during dimethylbenzanthracene (DMBA)-induced hamster cheek pouch carcinogenesis and the inhibitory effect of sulindac, a non-steroidal anti-inflammatory drug (NSAID), on the carcinogenesis and its derived squamous carcinoma cell line HCPC-1. From ...

The oxygen tension (Po2) on the external surface Qf arterioles between 8 and 100/JB in diameter was measured with oxygen microcathodes (2 to 6/x diameter) in the suffused cheek pouch of hamsters and in the cremaster muscle of hamsters and rats anesthetized with pentobaxbital and urethane. Intravascular Po2 was measured in 10 vessels and compared with extravascular Po2. Good agreement was found,...

To examine the role of reactive oxygen species on the invasive phenotype of cancer cells, we overexpressed manganese- and copper-zinc-containing superoxide dismutases (MnSOD, CuZnSOD) and catalase (Cat) in hamster cheek pouch carcinoma (HCPC-1) cells in vitro using adenoviral vector-mediated gene transfer. Hamster cheek pouch carcinoma cells were transduced with these adenoviral vector construc...

Intravital microscopy studies of small bundles of fibers of the extensor digitorum longus muscle grafted onto the hamster cheek pouch revealed a persistent reduction in the responsiveness of regenerated arterioles to vasoactive agents. We tested the hypothesis that the recovery of responsiveness to vasoactive agents by regenerating arterioles within whole, in situ autografted tibialis anterior ...

Vascular endothelial growth factor (VEGF) induces mild vasodilation and strong increases in microvascular permeability. Using intravital microscopy and digital integrated optical intensity image analysis, we tested, in the hamster cheek pouch microcirculation, the hypothesis that differential signaling pathways in arterioles and venules represent an in vivo regulatory mechanism in the control o...

Segal, Steven S., Suzanne E. Brett, and William C. Sessa. Codistribution of NOS and caveolin throughout peripheral vasculature and skeletal muscle of hamsters. Am. J. Physiol. 277 (Heart Circ. Physiol. 46): H1167–H1177, 1999.—In isolated cell systems, nitric oxide synthase (NOS) activity is regulated by caveolin (CAV), a resident caveolae coat protein. Because little is known of this interactio...