Effect of adrenalin, insulin and contractions on the content of the free fatty acid fraction in skeletal muscle.

The fraction of free fatty acids (FFA) is present in skeletal muscles. However, there is almost no data regarding regulation in the content of this intramuscular lipid pool. We took advantage of the isolated muscle preparation to examine whether: a) increasing exogenous concentration of FFA (500microM or 700microM, 30min) b) insulin (10.00 I.U./L, 30min), c) adrenalin (4.4 nM, 30 min), or d) contractions (200ms, tetani, 1Hz, 30min), affect the FFA content inside myocytes. Incubation of soleus (S) and extensor digitorum longus (EDL) with increasing concentrations of exogenous FFA (from 500microM to 700microM) resulted in an increase in the total FFA fraction in both muscles studied (by 280.2% and 259.1%, respectively). In contracting muscles FFA pool was significantly reduced both in S (by 73.1%) and in EDL (by 31.1%). Neither stimulation by adrenalin nor insulin affected the total content of FFA fraction in the muscles examined. We conclude that a) increased availability of exogenous FFA at the sarcolemma level results in an increase in the size of intramuscular FFA fraction b) the intracellular FFA fraction is utilized by contracting muscles with regard to the fiber composition and to a greater extent in more oxidative muscles, c) FFA fraction remains stable upon stimulation by insulin or adrenalin.     

Sulfation of hypertensive and hypotensive drugs by monkey brain phenol sulfotransferase

The substrate specificity and affinity of two forms of phenol sulfotransferase (PST) from Rhesus macaque brain cortex were studied. Catecholamines, their methylated metabolites (normetanephrine, metanephrine) and methylated precursor, -methylDOPA, were examined as substrates for both the cationic (PST I) and the anionic (PST II) forms of the enzyme. Sulfation of hypertensive drugs (phenylephrine, octopamine, metaraminol), hypotensive drugs (-methylDOPA, minoxidil), and related agents without a free hydroxy group on the benzene ring were also studied. Results indicated that both PST forms sulfated -methylDOPA and minoxidil, but only PST II transferred the sulfate group to catecholamines and most of the adrenergic agents examined.     

Arsenic in Agricultural Soils of a Historically Mined and Industrial Region of Southern Serbia and Northern Kosovo: Bioavailability and Uptake by Plants Species Zea mays L. and Solanum tuberosum L.

This article reports the results of a study focused on the presence and bioavailability of arsenic in agricultural soil in the mining and industrial regions of northern Kosovo and southern Serbia, as well as uptake and bioaccumulation of arsenic in two commonly cultivated plant species (Zea mays L. and Solanum tuberosum L.). This area was one of the most important mining districts in Europe. The collected soil samples were subjected to a modified BCR three-step sequential extraction procedure in order to investigate the chemical partitioning of arsenic in the soils. The general distribution of arsenic in various fractions was: exchangeable < reducible < oxidizable fractions. Highest concentrations of total arsenic in soil were found close to industrial facilities and tailing ponds. In addition, fluvisols were significantly more enriched with arsenic than soils at a distance from the river flows. The edible parts of the plant specimen showed different As contents, suggesting that these plant species have different propensities for the uptake and bioaccumulation of arsenic from soil.