Liver susceptibility to ischaemia in spontaneously hypertensive rats

Blood loss has previously been shown to be more detrimental for spontaneously hypertensive (SHR) than for normotensive Wistar-Kyoto (WKY) rats. To evaluate whether this decreased tolerance to blood loss is due to disturbances in circulatory control or to alterations in cellular function caused by the hypertensive disease, SHR and WKY were subjected to complete liver ischaemia. During a 45-min period of ischaemia as well as after 4 h of reflow, the liver content of ATP, glycogen, glucose and lactate was determined. Liver ATP decreased to 15% and liver glycogen to 30% of initial levels, while liver glucose increased 6-fold and liver lactate 13-fold during the ischaemic period in both SHR and WKY. Following 4 h of reflow, ATP was restored to 11.5 +/- 1.7 mumol X g protein-1 (56% of initial level) in SHR and to 15.2 +/- 1.3 (76%) in WKY. The levels of lactate and glucose returned to control levels after the reflow period while the glycogen stores were further depleted in SHR as well as WKY. No difference between SHR and WKY in cellular metabolic function during the ischaemic period could thus be demonstrated, and the postischaemic recovery was not significantly different. It is concluded that hypertensive disease does not seem to change the ischaemic tolerance of liver cells to any considerable extent.