The culture of human tumors in the cheek pouch of the golden hamster (l^t) provides hu man cancer tissue for study of the effects of therapeutic radiation with minimal complications introduced by radiation of the host. EversiÃ3n of the pouch bearing the tumor permits its exposure, while the rest of the hamster is shielded. The tu mor grows in the loose submucosal areolar tissue of the pouch and...

Introduction Diethylstilbestrol (DES) is the classic example of an endocrine disruptor and exemplifies the damage done by xenoestrogens. DES is a non-steroidal, synthetic estrogen that was developed to supplement a woman's natural estrogen production. DES was first prescribed by physicians in 1938 for women who experienced miscarriages or premature deliveries that were believed due to insuffici...

The rapid disappearance of infective forms of Trypanosoma cruzi from the site of inoculation as well as the initial phase of infection produced by the parasite are not yet fully understood. To investigate this problem we used the hamster as an animal model considering the existence of the cheek pouch--a peculiar region devoid of lymphatic vessels. T. cruzi trypomastigotes were inoculated into t...

Prodigious food hoarding in Syrian hamsters Mesocricetus auratus Waterhouse is strongly linked to appetite and is made possible by large internal cheek pouches. We provide a functional analysis of the cheek pouch and its associated retractor muscle. Frame-by-frame analysis of videotaped pouch-filling behavior revealed multiple jaw cycles for each food item pouched and the use of more jaw cycles...

OBJECTIVE Ischemic preconditioning and some drugs can protect tissues from injury by preserving microcirculation. This study evaluated vascular permeability in a hamster cheek pouch preparation using either short ischemic periods or bradykinin as preconditioning stimuli followed by 30 min of ischemia/reperfusion. METHOD Sixty-six male hamsters were divided into 11 groups: five combinations of...

The purpose of this study was to pharmacologically characterize the adenosine receptor subtype(s) that mediates adenosine-induced increases in macromolecular efflux from the intact hamster cheek pouch. Using intravital microscopy, we found that 1,3-dipropyl-8-(2-amino-4-chlorophenyl)-xanthine (PACPX), a selective adenosine receptor-1 antagonist, but not 3,7-dimethyl-1-propargylxanthine (DMPX), ...

OBJECTIVE We used the hamster cheek pouch microcirculation to investigate the effects of melatonin (ME) on ischemia reperfusion (I-R) injury by in vivo microscopy. ME is a hormone produced by the pineal gland and is the most powerful and effective hydroxyl radical scavenger detected to date in vitro. The second aim was to determine the scavenger effect of ME in cheek pouch microcirculation when...

The purpose of this study was to determine whether dexamethasone attenuates the acute increase in macromolecular efflux from the oral mucosa elicited by an aqueous extract of smokeless tobacco (STE) in vivo, and, if so, whether this response is specific. Using intravital microscopy, we found that 20-min suffusion of STE elicited significant, concentration-related leaky site formation and an inc...