The neurohormone melatonin is a key agent in synchronizing the circadian rhythms. At least three types of binding sites have been described for melatonin: the G-coupled, seven-transmembrane domain receptors mt1 and MT2 and a putative binding site called MT3. The latter has been described in hamster brain membranes, and its binding capacity is optimum at 4 degrees C. We further characterized thi...

The mucoprotein, which is responsible for the formation of gastric mucous gel in pig, has been shown to bind equally well to suspensions of baby hamster kidney cells, polyoma-virus-transformed baby hamster kidney cells and HeLa cells. The binding of the mucoprotein to the cells is dependent on Ca 2

The OT strain of mouse encephalomyelitis virus induces an inapparent infection in suckling hamsters associated with lesions of the central nervous system and skeletal muscles. The virus increases in pathogenicity after alternating mouse-hamster transfers and then induces both paralysis and encephalitis. Pathogenicity is lost through serial hamster passages but is restored by a single mouse tran...

Background: Busulfan is an alkylating agent, which inhibits cell dividing by sticking to one of the DNA strands. The aim of the present study was establishment and stereological evaluation of testes of azoospermic animal model using busulfan in albino hamster. Materials and Methods: Male adult albino hamsters were randomly assigned into 3 groups. The first group was injected one dose of busulfa...

We have previously found that cyclooxygenase-2 (COX-2), a key enzyme in the biosynthesis of prostaglandins (PGs), is present in the testicular interstitial cells of infertile men, whereas it is absent in human testes with no evident morphological changes or abnormalities. To find an animal model for further investigating COX-2 and its role in testicular steroidogenesis, we screened testes from ...

H AMSTER-to-rat transplantation has been widely used to study xenotransplantation between the relatively closely related species. Recently, we developed the surgical procedure for kidney transplantation in this species combination. This study describes mechanisms of hamster kidney graft rejection in the rat and the effect of different treatment protocols, including FK 506, cyclophosphamide, and...

In an attempt to isolate virus particles, a hamster macrophage cell line was examined by electron microscopy. This cell line was established from hamster macrophages infiltrating human lymphoid cells heterotransplanted in Syrian hamsters. The cultured cells appeared to be macrophages, containing round smooth nuclei with clear nucleoli, and numerous cytoplasmic primary lysosomes, polysomes, and ...

Cholesterol metabolism i n the hamster has been shown to resemble that in the human in many aspects, including bile acid production, whole body and hepatic cholesterol synthesis, the plasma lipoprotein profile 11 1. and the ability to produce lithogenic bile in response to various dietary manipulations 121. The hamster, therefore, should provide a good model for human cholesterol metabolism. Re...

PURPOSE Previous studies have suggested an important role of aberrant arachidonic acid metabolism, especially the cyclooxygenase (Cox) pathway, in oral carcinogenesis. However, it is unknown whether the 5-lipoxygenase (5-Lox) pathway contributes to oral carcinogenesis, and whether combination of inhibitors of both pathways may have synergistic or additive effects of chemoprevention. EXPERIMEN...

In this study, we report the cDNA cloning of hamster adrenal steroidogenic acute regulatory (StAR) protein and the effect of adrenocorticotrophin (ACTH) on its expression in vivo. A hamster adrenal cDNA library was screened using an 852 bp fragment obtained by polymerase chain reaction; this fragment corresponds to the entire coding sequence (CDS) of the hamster adrenal StAR cDNA. Ten clones of...