(33), by mixing 5 mL of dimethyl sulfoxide (DMSO) to the 10 mg recipient of CPA and then adding 252 [micro]L of such solution to each chamber already filled with 50 [micro]L of Krebs-Henseleit solution
Endothelium-free aortic rings were washed and exposed to calcium-free Krebs-Henseleit solution
(containing 100 [micro]mol/L EGTA) for 10 minutes.
All peptides were dissolved in distilled water, stored -20[degrees]C and diluted with modified Krebs-Henseleit solution
just before the infusions.
Once the vascular ring was adapted in the organ bath, we proceeded to stimulate the tissue response during the first hour of experimentation adding KCl (25 mM) every 20 minutes, and continuously changing the Krebs-Henseleit solution
. After the first hour had elapsed, and once the stabilization of the tissue was reached, a concentration curve vs.
To determine an influence of TAAC on calcium influx of smooth muscle cells, arterial rings of rats were equilibrated in Ca2+-free Krebs-Henseleit solution
containing 0.2 mM EGTA and washed three times with this solution at 20 min intervals.
Modified Krebs-Henseleit solution
(M K-HS) was employed as an incubation medium and it maintained a pH value of 7.35-7.45 throughout long-term experiments while heated up to 37 [degrees] C and bubbled with carbogen (95% [O.sub.2] + 5% [CO.sub.2]).
Euxanthone was added cumulatively during the tonic contractions induced by phenylephrine (3 [micro]M), and KCI (80 mM) in tissues previously suspended in normal Krebs-Henseleit solution
with the following composition (mM): NaCl 110.8, KCl 5.9, NaH[CO.sub.3] 25.0, Mg[SO.sub.4] 1.07, Ca[Cl.sub.2] 2.49, Na[H.sub.2]P[O.sub.4] 2.33 and glucose 11.51.
The left anterior descending coronary artery was removed and placed in Krebs-Henseleit solution
: NaCl 118, KCI 4.7, Ca[Cl.sub.2] 2.5, Mg[SO.sub.4] 1.2, K[H.sub.2][PO.sub.4] 1.18, NaH[CO.sub.3] 25, glucose l0mM.
All subsequent dilutions were prepared in Krebs-Henseleit solution
and kept in a cold and dark medium.
The proximal ileum was remove,d washed and placed in Krebs-Henseleit solution
. 1 cm segments were placed in 10 ml organ baths with a resting tensionof 1.0 g (preload).
The viscera were exposed and a segment of the superior mesenteric artery excised, free of fat and connective tissue, cut into rings about 2-3 mm in length and set up in gassed (95% [O.sub.2] and 5% C[O.sub.2]) Krebs-Henseleit solution
of the following composition (mM): NaCl 110.8, KC1 5.9, NaHC[O.sub.3] 25.0, MgS[O.sub.4] 1.07, Ca[Cl.sub.2] 2.49, Na[H.sub.2]P[O.sub.4] 2.33 and glucose 11.51.
The proximal ileum was removed, washed and placed in Krebs-Henseleit solution
. Segments of 1 cm were placed in 10 ml organ baths with a resting tension of 0.5 g (preload).