Alteration of cellular electrophysiologic properties in porcine pulmonary microcirculation after preservation with University of Wisconsin and Euro-Collins solutions.
BACKGROUND
The effect of cold storage of porcine pulmonary microvessels in University of Wisconsin (UW) and Euro-Collins (EC) solutions on the cellular electrophysiologic properties remains unknown.


METHODS
The pulmonary microarteries (PA, 381.6 +/- 62.8 microm; n = 60) and microveins (PV, 360.8 +/- 54.5 microm; n = 60) were incubated with Krebs (control), UW, or EC solution at 4 degrees C for 4 hours in a myograph. The resting membrane potential and the endothelium-derived hyperpolarizing factor-mediated hyperpolarization to bradykinin (0.1 micromol/L) in the presence of inhibitors of nitric oxide and prostacyclin, N(omega)-nitro-l-arginine, hemoglobin, and indomethacin, in a single smooth muscle cell were directly measured.


RESULTS
The resting membrane potential (-60.8 +/- 1.3 mV in PA and -48.1 +/- 0.7 mV in PV, n = 6) was depolarized after exposure to UW solution (to -18.4 +/- 0.7 mV in PA and -13.6 +/- 0.8 mV in PV; n = 8; p < 0.001). The amplitude of endothelium-derived hyperpolarizing factor-mediated hyperpolarization to bradykinin was also decreased (from 7.4 +/- 0.7 mV to 2.6 +/- 0.7 mV in PA and from 4.6 +/- 0.5 mV to 0.9 +/- 0.4 mV in PV; p < 0.001). In comparison, EC depolarized the membrane potential to a lesser extent (to -28.3 +/- 0.9 mV in PA and to -21.3 +/- 0.8 mV in PV; n = 8; p < 0.001) and almost abolished the hyperpolarization to bradykinin. After washout, hyperpolarization was partially restored (UW, 4.9 +/- 0.7 mV in PA and 2.0 +/- 0.3 mV in PV. p < 0.01; EC, 2.3 +/- 0.5 mV in PA and 1.0 +/- 0.3 mV in PV. p < 0.01).


CONCLUSIONS
Cold storage of porcine PA and PV with UW or EC solution impairs the electrophysiologic properties (hyperpolarization) related to endothelium-smooth muscle interaction. The alteration is more profound with EC than UW solution and in veins than in arteries. The findings urge further studies on lung preservation solutions.
Zhang
Rong-Zhen
RZ
Department of Surgery, The Chinese University of Hong Kong, Hong Kong SAR, China.
Yang
Qin
Q
Yim
Anthony P C
AP
He
Guo-Wei
GW
D000241:Adenosine / Q000494:pharmacology*; D000493:Allopurinol / Q000494:pharmacology*; D000818:Animals; D001160:Arterioles / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D001920:Bradykinin / Q000494:pharmacology; D004594:Electrophysiology; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005978:Glutathione / Q000494:pharmacology*; D006982:Hypertonic Solutions / Q000494:pharmacology*; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology*; D008168:Lung / Q000098:blood supply*; D008564:Membrane Potentials; D008833:Microcirculation; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D019335:Nitroarginine / Q000494:pharmacology; D009926:Organ Preservation; D019188:Organ Preservation Solutions; D010108:Oxyhemoglobins / Q000494:pharmacology; D011887:Raffinose / Q000494:pharmacology*; D013552:Swine; D014699:Venules / Q000166:cytology / Q000187:drug effects / Q000502:physiology*
D004791:Enzyme Inhibitors; C037096:Euro-Collins' solution; D006982:Hypertonic Solutions; D007328:Insulin; D019188:Organ Preservation Solutions; D010108:Oxyhemoglobins; C055206:University of Wisconsin-lactobionate solution; D019335:Nitroarginine; D000493:Allopurinol; D005978:Glutathione; D000241:Adenosine; D011887:Raffinose; D001920:Bradykinin; D007213:Indomethacin