Effects of Surgical Anaesthesia on the Viability of Nigral Grafts in the Rat Striatum

The effects of anaesthesia on cortical stimulation in rats: a functional MRI study

The purpose of this study was to investigate the affects of equithesin and isoflurane on cortical activation in the rat using fMRI. Eight healthy male Sprauge-Dawley rats were anaesthetised separately with isoflurane and equithesin following a week in between. Functional EPI images were acquired in axial and sagittal orientations on a Bruker 47/30 Biospec system. Each experiment included repetitive air puffs over the right face region and was divided into 4 OFF (no stimulation) and 3 ON (repeated air puffs) periods. Changes in the BOLD-fMRI signal response were analysed using a box-car response function (SPM99) correlated against each voxel to determine regions of activation (p Corrected <0.0001, Z score>3.54). Neural activation was not detected when equithesin was used except in one rat compared to consistent activation with isoflurane in all 16 functional EPI scans. Equithesin appears to have effectively reduced brain activity in response to sensory stimuli. Isoflurane anaesthesia (1.6%) showed consistent, robust neural activations. It is therefore recommended that equithesin should be further investigated with other functional modalities or behavioural tests prior to consider it as an anaesthetic agent for future functional MRI studies.

Effects of anaesthetics and lazaroid U-83836E on survival of transplanted rat dopaminergic neurones

We investigated whether different methods of anaesthesia, used on the pregnant rat when collecting embryonic donor tissue, and a lipid peroxidation inhibitor (lazaroid U-83836E) affect the survival of grafted embryonic dopaminergic neurones in hemiparkinsonian rats. There was no difference in either functional recovery or survival of dopaminergic neurones between the different euthanasia groups: (a) isoflurane sedation followed by cervical dislocation, (b) equithesin- or (c) euthatal-anaesthesia. However, lazaroid-treatment enhanced both behavioural recovery and transplant survival.