L ng nitroarginine l nna

For electrophysiological and Ca²⁺ imaging experiments, tissues were constantly perfused with oxygenated KRB of the following composition (mM): NaCl 118.5; KCl 4.5; MgCl₂ 1.2; NaHCO₃ 23.8; KH₂PO₄ 1.2; dextrose 11.0; CaCl₂ 2.4. The pH of the KRB was 7.3–7.4 when bubbled with 97% O₂-3% CO₂ at 37±0.5°C. Muscles were left to equilibrate for at least 1 hour before experiments were begun. L-N^G-Nitroarginine (L-NNA) and atropine were obtained from Sigma (St Louis, MO, USA), 2-Iodo-N⁶-methyl-(N)-methanocarba-2’-deoxyadenosine-3’,5’-bisphosphate tetraammonium salt (MRS2500) was purchased from Tocris Bioscience (Ellisville, MO). Nifedipine was purchased from Sigma-Aldrich (St. Louis, MO), dissolved in ethanol to a concentration of 10 mM and added to the perfusion KRB solution at a final concentration of 1 μM.

Guanethidine sulfate, carbachol (CCh), mouse recombinant resistin, recombinant full-length mouse adiponectin (ADPN), tetrodotoxin (TTX) and L-N^G-nitro arginine (L-NNA) were obtained from Sigma Chemical (St. Louis, MO, USA), while resistin was purchased from PeproTech (London, UK). Solutions were prepared on the day of the experiment, except for TTX, ADPN and resistin, for which stock solutions were kept stored at −20 °C. Drug concentrations are referred to as final bath concentrations and are in the range of those previously reported to be effective in isolated smooth muscle tissues [23 (link),24 (link),37 (link),38 (link)].