Uterine and umbilical uptakes of alanine (Ala) were measured in 10 ewes before (control) and during intravenous infusion of Ala, which increased maternal arterial Ala concentration from 115 ± 14 to 629 ± 78 μM ( P < 0.001). In 8 of these ewes, placental Ala fluxes were traced by constant intravenous infusion ofl-[3,3,3-2H3]Ala in the mother andl-[1-13C]Ala in the fetus. Rates are reported as mi...

The nonvolatile orgainic acicls uncloubte(dly play a role in fruit ripening as they (1o in many other metabolic processes. As an approach to definiing this role in the banania fruit, informatioin is needled on the nature of these acids and on the chainges which occur dluring ripening. Earlier reports (23) indicate the presence of nmalic, citric, oxalic, an(l tartaric acids in the banana fruit, ...

In the chicken intestine,l-methionine is transported by systems that are specific for neutral amino acids (L- and B-like) and by systems that can also transport cationic amino acids (y+m and b0,+-like). These four uptake pathways have been investigated in brush-border membrane vesicles from the jejunum of chickens fed a diet enriched with 0.4%l-methionine. Methionine supplementation from the 1s...

At least 10 clifferent metabolic pathwvavs leadling to the formation of malonlate have beenl rieported. The enzymes participatiing in these pathways include: AcetylCoA carboxylase (6, 10, 11, 20, 37), transcarboxylase (1, 10, 14, 15, 16, 24), thiokinase and thioesterase (11), barbiturase (12), malonic senmialdehyde dehydrogenase (22, 31, 32), B-alanine transaminase (18), AcylCoA-CO., exchange (...

Reperfusion of ischemic intestine is associated with P-selectin-dependent adhesion of leukocytes in the liver microcirculation. The objective of this study was to define the contribution of nitric oxide (NO) to the enhanced P-selectin expression and increased leukocyte rolling elicited by gut ischemia-reperfusion (I/R). Leukocyte rolling (monitored by intravital microscopy) in the terminal hepa...

The respiration of slices of a variety of bulky storage tissues rises gra(lually three to fourfold within a (lay of cutting (7, 8, 9, 10). The respiration rate of freslh tissue cani be sharply raise(d ith 2,4 dinitrophenol, however, as (lemionstrate(I in chlicory and potato slices. Both the age-inducedI an(d DNPinducedl respiration incremzents are inhibite(d by imalonate. It has been sh]own tha...

Summetlary. The effect of sodium chloride added to root medium of pea seedlings on respiratory activity of tissue segments and on isolated mitochondria was studied. Salinization enhances the respiration of leaves about one-third on a fresh weight, dry weight or protein basis. Roots and stems show only 10 to 15 % respiratory stimuilation. The onset of respiratory increase in leaves rouighly para...

The present study was designed to evaluate the role of the endothelium as an effector organ of neurally mediated inhibition of vascular tone. Acetylcholine (ACh), either released by stimulation of the submucosal ganglia or applied exogenously, inhibited phenylephrine (PE)-induced constrictions in arterioles of the guinea pig intestinal submucosa. N G-monomethyl-l-arginine (l-NMMA), an inhibitor...

The effect of orally administered insulin-like growth factor-I (IGF-I) on small intestinal structure and function was studied in 5-day-old colostrum-deprived piglets. Human recombinant IGF-I (3.5 mg ⋅ kg-1 ⋅ day-1) or control vehicle was given orogastrically for 4 days. Body weights, jejunal and ileal mucosa wet and dry weights, and serum IGF-I levels were similar in the two groups. Small intes...

N G-nitro-l-arginine methyl ester (l-NAME; 250 μg/5 μl), an inhibitor of NO synthase, or the vehicle artificial cerebrospinal fluid (aCSF; 5 μl) was administered intracerebroventricularly to conscious rats hemorrhaged (0.7 ml/min) to a 20% volume depletion. Hypotension was maximal 5 min after hemorrhage ended, with compensatory recovery to basal levels 20 min later, regardless of drug treatment...