The relationship between glutamate release and cerebral blood flow after focal cerebral ischaemia in the cat: effect of pretreatment with enadoline (a kappa receptor agonist).

The effect of the kappa-opioid agonist enadoline (CI-977) upon the relationship between cerebral blood flow and glutamate release was simultaneously assessed (using microdialysis and hydrogen clearance techniques respectively) at the same anatomical locus in the cerebral cortex (suprasylvian gyrus) after permanent middle cerebral artery (MCA) occlusion in halothane-anaesthetised cats. During controlled graded ischaemia, pretreatment with enadoline (0.3 mg/kg i.v. followed by continuous infusion at 0.15 mg/kg/h), initiated 30 min prior to MCA occlusion, significantly attenuated the marked increases in extracellular glutamate, aspartate and GABA observed in the focal ischaemic penumbra. The present data are consistent with the hypothesis that the neuroprotective efficacy of enadoline in focal cerebral ischaemia is due to inhibition of glutamate release in the ischaemic penumbra.

Therapeutic potential of endothelin receptor antagonists in experimental stroke.

This investigation demonstrates an increase in endothelin (ET)-mediated vascular tone in peri-ischemic areas after experimental focal cerebral ischemia (middle cerebral artery occlusion) in the cat. Adventitial application of the butenolide antagonist PD155080 (30 microM), after MCA occlusions resulted in marked increases in caliber of dilated (10.6 +/- 1.6% change from preinjection baseline) and constricted vessels (68.7 +/- 17.5% change from pre-injection baseline). Cerebral blood flow (measured by laser Doppler flowmetry) was reduced after MCA occlusion to 50% of preocclusion levels. Intravenous administration of PD156707 30 min after MCA occlusion restored cerebral blood flow to preocclusion baseline levels at 6 h. The volume of ischemic damage in the cerebral hemisphere after MCA occlusion was significantly reduced (by 45%) after intravenous administration of PD156707.

The management outcome of patients with a ruptured posterior circulation aneurysm.

From 1979-1986 121 patients with a vertebro basilar aneurysm were admitted to the Institute of Neurological Sciences, Glasgow. Of the 121 patients, 97 presented with a subarachnoid haemorrhage. In these patients the management mortality was 30% and the operative mortality 13%. Sixteen patients rebled and 16 developed delayed ischaemia. The prognosis of a patient with a ruptured vertebro basilar aneurysm admitted to our Institute is similar to that of a patient with aneurysmal subarachnoid haemorrhage from an anterior circulation aneurysm.

Carotid traumatic aneurysm treated by detachable balloon.

The authors report the case of a young man who developed a large infraclinoid carotid aneurysm following a blunt head injury and presented with epistaxis. The aneurysm was occluded by a detachable balloon resulting in a good recovery.

Magnetic resonance imaging in the management of resistant focal epilepsy: pathological case report and experience of 12 cases.

Clinical improvement in epilepsy following temporal lobectomy is more often obtained when an abnormality is found on subsequent histological examination. Pre-operative MRI demonstrated an abnormal signal in the temporal lobe of a patient with pathologically proven mesial temporal sclerosis with microvascular anomaly. MRI may therefore be helpful in the selection of patients for temporal lobectomy. MRI findings of 12 patients with resistant focal epilepsy are reviewed. A wide range of T1 and T2 weighting is suggested to maximise selection of patients.

Necropsy study of mountaineering accidents in Scotland.

One hundred and twenty one people died in mountaineering accidents in Scotland between July 1978 and December 1983. Necropsies were carried out on 42, which form the basis of this report. In 21 cases head injury was major fatality factor, but in 11 of these there were also serious chest injuries. Focal brain damage (haematomas, contusions, or lacerations) was more common (n = 21) than diffuse brain damage (n = 18). Over half of the victims with severe head injury had few other injuries and would probably have survived had the head injury been prevented. Spinal injuries usually occurred with other major injuries. Chest injuries were common, being serious in 18 cases, but abdominal injuries were uncommon. Four climbers with only minor injuries died of hypothermia.

Infection after depressed fracture in the west of Scotland.

Of 216 compound depressed fractures of the skull seen between the years 1974-1978, nine (4%) became infected. This is significantly less than the 10% found in previous years. Efforts are being intensified to train primary surgeons, stressing the importance of immediate referral and early treatment.

Categories of axons in mammalian rami communicantes. Part II.

The mammalian rami communicantes consist of preganglionic, postganglionic and sensory axons. The present study focusses on the number of sensory axons in the midthoracic rami communicantes in the cat. The conclusions are that the white rami contain approximately 250 myelinated and 200 unmyelinated sensory axons and the grey rami 4 to 5 myelinated and 20 to 25 unmyelinated sensory axons. A previous study determined the numbers of pre- and postganglionic fibers in these same rami. Thus the total number of axons in these rami are as follows: for the grey rami there are: (1) 3,000 to 5,000 unmyelinated postganglionic axons, (2) 25 myelinated postganglionic axons, (3) 20 to 25 unmyelinated sensory axons and; (4) 4 to 5 myelinated sensory axons; and for the white rami there are approximately: (1) 1,000 unmyelinated preganglionic axons, (2) 1,500 myelinated preganglionic axons, (3) 2,000 unmyelinated postganglionic axons, (4) 250 unmyelinated sensory axons and (5) 200 myelinated sensory axons. The implications of these findings are discussed.