Medical Toxicology Commons^™

Regulation Of The Rat Liver Sodium-Dependent Bile Acid Cotransporter Gene By Prolactin. Mediation Of Transcriptional Activation By Stat5, Tanmoy C. Ganguly, Michelle L. O'Brien, Saul J. Karpen, James F. Hyde, Fredrick J. Suchy, Mary Vore

Toxicology and Cancer Biology Faculty Publications

The intracellular mechanism(s) underlying the upregulation of the hepatic Na+/taurocholate cotransporting polypeptide (ntcp) by prolactin (PRL) are unknown. In this report, we demonstrate a time-dependent increase in nuclear translocation of phosphorylated liver Stat5 (a member of the ignal ransducers and ctivators of ranscription family) that correlated with suckling-induced increases in serum PRL levels. In electrophoretic mobility gel shift assays, nuclear Stat5 exhibited specific DNA-binding ability towards IFN-gamma-activated sequence (GAS)-like elements (GLEs; 5'TTC/A-PyNPu-G/TAA-3') located in the -937 to -904 bp region of the ntcp promoter. Transient cotransfections in HepG2 cells revealed that PRL inducibility (2.5-3-fold) required coexpression of the long form …

Dna-Protein Cross-Linking By Pyrrolizidine Alkaloids, Gail L. Drew

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pyrrolizidine alkaloids (PAs) are natural plant compounds found in hundreds of plant species worldwide and are reported to have cytotoxic, carcinogenic, antimitotic, and genotoxic activity. PAs are metabolized by the cytochrome P450 (CYP) system to the pyrrole or the N-oxide form. The pyrroles are bifunctional electrophilic alkylators that bind cellular nucleophiles such as DNA and proteins and sirupt normal cell processes, including DNA replication and gene transcription and can cause megalocytosis. The pyrroles dehydrosenecionine (DHSN) and dehydromonocrotaline (DHMO) are among the most potent PA cross-linkers and inducers of megalocytosis. DHSN and DHMO-induced cross-links in cultured normal (MDBK) and neoplastic (MCF7) …

Aflatoxin B1 Metabolism In Mammalian Pulmonary Tissue, J. Michael Eichelberger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aflatoxin B₁ (AFB₁) is a potent dietary hepatocarcinogen and may be a lung carcinogen when inhaled. To study the relative ability of lung and liver to metabolize AFB₁, a susceptible (Swiss-Webster rat) and resistant species (Syrian golden hamster) were pretreated with inducing agents in order to identify specific AFB₁ metabolizing enzymes in each tissue.

Analysis of AFB₁-exo-epoxide (AFBO) formation, O-dealkynation assays, and protein immunoblots demonstrated that cytochrome P450 (CYP) 1A proteins were overexpressed in both the lung and liver of hamsters pretreated with 3-methylchyolanthrene (3-MC). Only CYP1A1 was expressed in the lung …

Proton (H) Modulation Of K-Cl Cotransport Through Both Internal And External Sites In Dids-Ph-Clamped Low Magnesium Lk Sheep Erythrocytes, Peter K. Lauf, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.