Pathophysiological implications of the vascular nitric oxide (NO)/cGMP pathway were investigated in various rat models of hypertension. The expression of brain and endothelial constitutive NO synthases (bNOS, ecNOS) was determined by Western blot analysis, and the biochemical activity of soluble and particulate guanylate cyclases (GC) was assessed by the amount of cGMP generated in the thoracic aortae of rats with deoxycorticosterone acetate (DOCA)-salt, two-kidney, one dip (2K1C), and spontaneous hypertension (SHR). Plasma nitrite/ nitrate levels were decreased in DOCA-salt and 2K1C hypertension, and increased in SHR. The vascular expression of bNOS as well as that of ecNOS was decreased along with tissue nitrite/nitrate contents in DOCA-salt and 2K1C hypertension. The expression of both bNOS and ecNOS was increased in SHR with concomitant changes of tissue nitrite/nitrate contents. The activity of soluble GC was decreased, and that of particulate GC was increased in DOCA-salt hypertension. The soluble GC activity was increased, while the particulate GC activity was not affected in 2K1C hypertension. The soluble GC activity was not significantly changed, but the particulate GC activity was decreased in SHR. These results indicate that the high blood pressure is associated with differentially-altered vascular NO/cGMP pathway in different models of hypertension.
Animal ; Aorta, Thoracic/enzymology ; Atrial Natriuretic Factor/blood ; Blotting, Western ; Desoxycorticosterone ; Guanylate Cyclase/metabolism ; Guanylate Cyclase/analysis* ; Hypertension/enzymology* ; Hypertension/chemically induced ; Isoenzymes/metabolism ; Isoenzymes/analysis* ; Male ; Nitrates/blood ; Nitric-Oxide Synthase/metabolism ; Nitrites/blood ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY ; Rats, Sprague-Dawley ; Solubility

PURPOSE: Adriamycin(R) is one of the most commonly used drugs in the treatment of breast cancer. This study was performed to understand the molecular mechanisms of drug resistance in breast cancer cells. MATERIALS AND METHODS: We have analyzed the MCF-7 breast cell line and its adriamycin-resistant variants, MCF-7/ADR using human 10 K element cDNA microarrays. RESULTS: We defined 68 genes that were up-regulated (14 genes) or down-regulated (54 genes) in adriamycin resistant breast cancer cells. Several genes, such as G protein-coupled receptor kinase 5, phospholipase A2, guanylate cyclase 1, vimentin, matrix metalloproteinase 1 are up-regulated in drug resistant cells. Several genes, such as interferon, alpha-inducible protein 27, forkhead box M1, mitogen-activated protein kinase 6, regulator of mitotic spindle assembly 1 and tumor necrosis factor superfamily are down-regulated in adriamycin resistant cells. The altered expression of genes observed in microarray was verified by RT-PCR. CONCLUSION: These findings show that cDNA microarray analysis can be used to obtain gene expression profiles reflecting the effect of anticancer drugs on breast cancer cells. Such data may lead to the assigning of signature expression profiles of drug-resistant tumors which may help predict responses to drugs and assist in the design of tailored therapeutic regimens to overcome drug resistance.
Breast Neoplasms* ; Breast* ; Cell Line ; DNA, Complementary* ; Doxorubicin* ; Drug Resistance ; Gene Expression* ; Guanylate Cyclase ; Humans ; Interferons ; Matrix Metalloproteinase 1 ; Mitogen-Activated Protein Kinase 6 ; Oligonucleotide Array Sequence Analysis* ; Phospholipases A2 ; Phosphotransferases ; Spindle Apparatus ; Transcriptome* ; Tumor Necrosis Factor-alpha ; Vimentin

Acute pancreatitis is a multifactorial disease associated with the premature activation of digestive enzymes. The genes expressed in pancreatic acinar cells determine the severity of the disease. The present study determined the differentially expressed genes in pancreatic acinar cells treated with cerulein as an in vitro model of acute pancreatitis. Pancreatic acinar AR42J cells were stimulated with 10(-8) M cerulein for 4 h, and genes with altered expression were identified using a cDNA microarray for 4,000 rat genes and validated by real-time PCR. These genes showed a 2.5-fold or higher increase with cerulein: lithostatin, guanylate cyclase, myosin light chain kinase 2, cathepsin C, progestin-induced protein, and pancreatic trypsin 2. Stathin 1 and ribosomal protein S13 showed a 2.5-fold or higher decreases in expression. Real-time PCR analysis showed time-dependent alterations of these genes. Using commercially available antibodies specific for guanylate cyclase, myosin light chain kinase 2, and cathepsin C, a time-dependent increase in these proteins were observed by Western blotting. Thus, disturbances in proliferation, differentiation, cytoskeleton arrangement, enzyme activity, and secretion may be underlying mechanisms of acute pancreatitis.
Acinar Cells ; Animals ; Antibodies ; Blotting, Western ; Caerulein ; Cathepsin C ; Cytoskeleton ; Gene Expression ; Guanylate Cyclase ; Lithostathine ; Myosin-Light-Chain Kinase ; Oligonucleotide Array Sequence Analysis ; Pancreatitis ; Proteins ; Rats ; Real-Time Polymerase Chain Reaction ; Ribosomal Proteins ; Trypsin