Xiao-Ping Yang and Shigetoshi Chiba*
Department of Pharmacology, Shinshu University School of Medicine, Matsumoto
390 - 8621, Japan
* To whom correspondence should be addressed.
Abstract: The present study demonstrated the progressive inhibition
by prolonged cold storage (4, 7 and 14 days at 4) on prejunctional and
postjunctional functions of purinergic and adrenergic components of double-peaked
vasoconstrictor responses to periarterial electrical nerve stimulation in
the isolated canine splenic artery. After the cold storage for 4 days, the
first phase constriction was markedly decreased, whereas the second response
was not significantly modified. Furthermore, after the 7 days of cold storage,
the first phase was substantially depressed at low frequencies, but at high
frequencies, a low level of contractile responses was still observed. On
the other hand, the second phase in the cold stored artery for 7 days largely
remained at any used frequencies. Moreover, the 14 days of cold storage
almost completely inhibited the vasoconstrictor responses to nerve stimulation.
Tyramine-induced constrictions were progressively decreased in the stored-days
dependent manner, although the ATP and the noradrenaline-induced one was
not modified for 4 and 7 days of the cold storage. In conclusion, 1) the
4 cold stored artery for 4 days may show preferential injury of its tyramine-dependent
noradrenaline releasing mechanisms, whereas nerve excited ones might well
remain; and 2) the prejunctional contractile response of purinergic transmission
might be damaged more preferentially than that of adrenergic transmission
within 7 days storage.
Keywords: Cold storage, Tyramine, Sympathetic nerve stimulation, Purinergic
transmission, Splenic artery