Because the immune response to human choriocarcinoma growing in the hamster cheek pouch makes it difficult to evaluate the responsiveness of the tumor to drugs, we have studied this immune response in untreated hamsters and hamsters immunologically suppressed with heterologous antilymphocyte serum (ALS). Untreated animals were immunized by the tumor beginning as early as 6 days after implantati...

Hamster cheek pouch skin, transplanted to the side of an isogenic host's chest wall, retains its immunologically privileged status as evidenced by the prolonged survival of inlaid homografts of ordinary skin. Various findings sustain the premise that exemption from rejection by otherwise susceptible homografts in both intact pouch tissue and in established pouch skin isografts is due to an impe...

the characteristics associated with hepatocytes. They have glucose 6-phosphatase activity, secrete serum globulin, and, in confluent monolayers, show tight cell junctions and intercellular canaliculi resembling bile canaliculi. On the other hand, the cells have low levels of inducible tyrosine aminotransferase, no detectable 6-aminolevulinic acid synthetase and aryl hydrocarbon hydroxylase acti...

Background We recently discovered that soluble guanylyl cyclase (sGC) activity is modulated by S-nitrosation, the addition of a NO moiety to the free thiol of cysteines (Cys). Pathologically, we observed that exposure to low, therapeutic levels of nitroglycerin in rats led to decreased vascular response to NO in the arterioles of hamster cheek pouch, which correlated with S-nitrosation and dese...

We found that silver, either as silver metal or silver chloride, exerted toxic effects on the smooth muscle of isolated cannulated hamster cheek pouch arterioles. Silver initially stimulated the smooth muscle, producing a marked vasoconstriction. The vessels then dilated back to control diameters. Once the arterioles began to dilate, they became refractory to norepinephrine or potassium stimula...

In many disorders of the cornea, blood vessels invade this normally avascular tissue. Several theories have been proposed to explain the pathogenesis of corneal vascularization. Since none had received general acceptance, experimental studies of the phenomenon were begun several years ago in hamster cheek pouch chambers. These investigations which employed sequential morphologic studies during ...

-The growth and metastatic spread of human tumours in immuno suppressed hamsters is described. A variety of human tumours were transplanted to the flank or the cheek pouch of the hamsters. Immunosuppression was obtained by combined thymectomy and ATS treatment. In the period up to 4 months after implantation, metastases to the lungs were observed with carcinomata of breast, colon, larynx and ki...

We expose methods for in vivo assessment of oxygen, nitric oxide (NO), and reactive oxygen species (ROS)/reactive nitrogen species (RNS), in the microcirculation during normoxia and hypoxia. We provide an example of the related mechanisms of ROS/RNS and oxygen level in the process of regulating capillary perfusion. Namely, we discuss the real time pO(2) measurements in vivo in the microvessels ...

BACKGROUND AND OBJECTIVES The development of 5-aminolevulinic acid (ALA)-induced tissue fluorescence is optimal 2-4 hours after ALA application. Goal of this work was to develop a means of accelerating oral topical ALA-induced tissue fluorescence. STUDY DESIGN/MATERIALS AND METHODS In 300 hamsters, DMBA (9,10 dimethyl-1,2-benzanthracene) cheek pouch carcinogenesis produced dysplasia in 3-5 we...