schneideri toad (50 [micro]g/mL) or at basal condition when preparations were incubated with Tyrode solution
(control) or methanolic extract for 5 min or 60 min (n = 3/group), were washed with the vehicle and then immersed in Karnovsky fixative (2% paraformaldehyde, 2.5% glutaraldehyde in 0.1 M sodium cacodylate buffer, pH 7.2).
The variants most commonly used for research purposes are Tyrode solution
(Kietzmann et al., 1993), Krebs-Henseleit solution (Berhane et al., 2006), and bicarbonated Krebs-Ringer solution (Hansen et al., 2004) (Tab.
For hypoxic challenges, H9c2 transfected cells were trypsinized, washed with Tyrode without glucose, and incubated with a modified Tyrode solution
simulating ischemic conditions (IT) (in mM: 135 NaCl, 8 KCl, 0.5 Mg[Cl.sub.2], 0.33 Na[H.sub.2]P[O.sub.4], 5 HEPES, 1.8 Ca[Cl.sub.2], and 20 Na+-lactate, pH 6.8)  and transferred into an anaerobic chamber with an oxygen level <1% at 37[degrees]C.
Standard HEPES-buffered tyrode solution
(air equilibrated) contained (mM)
where [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII]--the input resistance of Tyrode solution
Briefly, zonae pellucidae of blastocysts were removed by exposing the embryos in groups of ten to fifteen to acid Tyrode solution
, until the zonae pellucidae became wrinkly and dissolved (after about 3 to 5 second).
To investigate the time dependence of STV on pinacidil-induced sarc[K.sub.ATP] currents, we incubated the isolated myocytes in STV-containing tyrode solution
with different time at the concentration of 10 [micro]M.
After removal of the zona pellucida with acid tyrode solution
(Sigma), zona pellucida-free four-cell stage embryos were cultured to the blastocyst stage.
Between successive doses, the tyrode solution
was washed off and the muscle allowed to relax for 4-5 minutes.
The intestinal segment was immediately transferred to oxygenated Tyrode solution
(95% [O.sub.2] and 5% C[O.sub.2]) maintained at 37 [+ or -] 0.5[degrees]C and was cleared off the adhering tissue and rinsed with Tyrode solution
(containing arginine 0.8 [micro]M) was added to dilute and disperse RBCs for observation.
Tracheal ring strips were then mounted in a 5-ml tissue bath containing modified Tyrode solution
(composition in mM: NaCl 136.0, KCl 5.0, [MgCl.sub.2] 0.98, [CaCl.sub.2] 2.0, [NaH.sub.2][PO.sub.4] 0.36, [NaHCO.sub.3] 11.9 and glucose 5.5 (pH 7.4)) maintained at 37 [o.bar]C to study the tracheal muscle relaxation.