Effects of Bilateral Carotid Artery Ligation on Brain Lactate and Pyruvate Concentrations in Normotensive and Spontaneously Hypertensive Rats

Abstract

Brain lactate, pyruvate, and arterial acid-base balance were measured in normotensive rats (NTR) and spontaneously hypertensive rats (SHR) 60 minutes after bilateral carotid artery ligation. Brain lactate and lactate-pyruvate ratios were significantly increased in both SHR and NTR following carotid occlusion, although lactate increase in the former was six and one-half times greater than in the latter. These findings suggest that bilateral carotid occlusion in SHR may cause more severe circulatory changes which result in increased anaerobic metabolism. Furthermore, higher brain lactate was concomitant with lower arterial carbon dioxide tension. The mechanism of spontaneous hyperventilation following cerebral ischemia was discussed.