The interaction of homocysteine and copper markedly inhibits the relaxation of rabbit corpus cavernosum: new risk factors for angiopathic erectile dysfunction?

Objectives: To explore whether homocysteine (HCy), an independent risk factor for atherosclerosis (the angiopathic effect of which occurs through the generation of superoxide anions and hydrogen peroxide, augmented by copper, the superoxide anions reacting with nitric oxide, NO, to produce peroxynitrite, a highly angiopathic free radical) and copper contribute to erectile dysfunction (ED) through similar mechanisms, by assessing their interactive effects on the relaxation of corpus cavernosum using organ-bath techniques.

Materials And Methods: Cavernosal smooth muscle strips were obtained from adult New Zealand White rabbits and mounted in organ baths. After precontraction with phenylephrine (100 micromol/L), relaxation responses to carbachol or sodium nitroprusside (SNP) were assessed in the presence or absence of HCy and copper.

Investigation of the inhibitory effects of homocysteine and copper on nitric oxide-mediated relaxation of rat isolated aorta.

1. Elevated plasma levels of homocysteine (HC) and copper have both been associated with the development of inflammatory vascular diseases, such as atherosclerosis. In this study, the effects of a combination of HC and copper on nitric oxide (NO)-mediated relaxation of isolated rat aortic rings were investigated.

Integration of classical and molecular approaches of genetic selection: egg production.

Poultry breeding has demonstrated success from the use of a complex mixture of assessment tools. New proposals are regularly sought out and tested for their ability to translate data into information that enhances genetic gain from selection. Details long hidden from view are already being uncovered by molecular genetics, calling for great skill and discipline to discern and harness their real potential.

Endogenous viral genes influence infection with avian leukosis virus.

The influence of endogenous viral (ev) genes on avian leukosis virus (ALV) infection was studied in ALV-free white leghorn chickens exposed to chicks from ALV shedding dams. The study included four lines, each segregating for one ev gene, one line free of ev genes, and four commercial stocks segregating for a number of ev genes. Genes ev12 and ev21 that produce the complete endogenous virus were associated with significant reductions in antibody response to ALV.

Nucleolar size polymorphisms in commercial layer chickens; determination of incidence, inheritance, and nucleolar sizes.

In the chicken, one chromosome pair encodes the ribosomal (r)RNA genes and two nucleoli are formed in interphase cells. The nucleolus is the site of rRNA synthesis and ribosome biogenesis. Nucleolar size polymorphisms have been detected in research strains of chickens and found to represent heterozygosity for rRNA gene copy number.

Effects of genetic strain, slow versus rapid-feathering maternal genotype, and cage density on the performance of Single Comb White Leghorns.

Two hatches involving 11,158 pullets from 22 Single Comb White Leghorn strain crosses were used in these experiments: 13 from rapid-feathering (k+/-) and 9 from slow-feathering (K/-) dams, some of which shared common genetic backgrounds; and all from 5 homozygous k+ sire types. Birds were grown intermingled within hatch, and were subsequently caged in two laying houses, one with 30.5 cm x 40.