Inhibitory action of novel hydrogen sulfide donors on bovine isolated posterior ciliary arteries

This is the author’s version of a work that was accepted for publication in Experimental Eye Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Experiemental Eye Research, Vol. 134, (2015) doi:10.1016/j.exer.2015.04.001.In the present study, we investigate the inhibitory effect of novel H2S donors, AP67 and AP72 on isolated bovine posterior ciliary arteries (PCAs) under conditions of tone induced by an adrenoceptor agonist. Furthermore, we examined the possible mechanisms underlying the AP67- and AP72-induced relaxations. Isolated bovine PCA were set up for measurement of isometric tension in organ baths containing oxygenated Krebs solution. The relaxant action of H2S donors was studied on phenylephrine-induced tone in the absence or presence of enzyme inhibitors for the following pathways: cyclooxygenase (COX); H2S; nitric oxide and the ATP-sensitive K(+) (KATP) channel. The H2S donors, NaHS (1 nM - 10 μM), AP67 (1 nM - 10 μM) and AP72 (10 nM - 1 μM) elicited a concentration-dependent relaxation of phenylephrine-induced tone in isolated bovine PCA. While the COX inhibitor, flurbiprofen (3 μM) blocked significantly (p < 0.05) the inhibitory response elicited by AP67, it had no effect on relaxations induced by NaHS and AP72. Both aminooxyacetic acid (30 μM) and propargylglycine (1 mM), enzyme inhibitors of H2S biosynthesis caused significant (p < 0.05) rightward shifts in the concentration-response curve to AP67 and AP72. Furthermore, the KATP channel antagonist, glibenclamide (300 μM) and the NO synthase inhibitor, l-NAME (100 μM) significantly attenuated (p < 0.05) the relaxation effect induced by AP67 and AP72 on PCA. We conclude that H2S donors can relax pre-contracted isolated bovine PCA, an effect dependent on endogenous production of H2S. The inhibitory action of only AP67 on pre-contracted PCA may involve the production of inhibitory endogenous prostanoids. Furthermore, the observed inhibitory action of H2S donors on PCA may depend on the endogenous biosynthesis of NO and by an action of KATP channels.National Institutes of Health/National Eye Institute Gran

Patterning in Birthweight in India: Analysis of Maternal Recall and Health Card Data

National data on birthweight from birth certificates or medical records are not available in India. The third Indian National Family Health Survey included data on birthweight of children obtained from health cards and maternal recall. This study aims to describe the population that these data represent and compares the birthweight obtained from health cards with maternal recall data in terms of its socioeconomic patterning and as a risk factor for childhood growth failure.The analytic sample consisted of children aged 0 to 59 months with birthweight data obtained from health cards (n = 3227) and maternal recall (n = 16,787). The difference between the card sample and the maternal recall sample in the distribution across household wealth, parental education, caste, religion, gender, and urban residence was compared using multilevel models. We also assessed the ability of birthweight to predict growth failure in infancy and childhood in the two groups. The survey contains birthweight data from a majority of household wealth categories (>5% in every category for recall), both genders, all age groups, all caste groups, all religion groups, and urban and rural dwellers. However, children from the lowest quintile of household wealth were under-represented (4.73% in card and 8.62% in recall samples). Comparison of data across health cards and maternal recall revealed similar social patterning of low birthweight and ability of birthweight to predict growth failure later in life. Children were less likely to be born with low birthweight if they had mothers with over 12 years of education compared to 1-5 years of education with relative risk (RR) of 0.79 (95% confidence interval [CI]: 0.52, 1.2) in the card sample and 0.70 (95% CI: 0.59, 0.84) in the recall sample. A 100 gram difference in a child's birthweight was associated with a decreased likelihood of underweight in both the card (RR: 0.95; 95% CI: 0.94, 0.96) and recall (RR: 0.96; 95% CI: 0.96, 0.97) samples.Our results suggest that in the absence of other sources, the data on birthweight in the third Indian National Family Health Survey is valuable for epidemiologic research