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1. The systemic effects of inhaled fluticasone propionate (FP), administered via Diskhaler, on the hypothalamo‐pituitary‐adrenal (HPA) axis were assessed primarily by measuring plasma cortisol at frequent intervals for 20 h after drug administration. 2. FP showed a dose‐ related suppression of plasma cortisol measured as area under the plasma cortisol vs time curve (AUC 0‐20). The cortisol suppression (expressed as % fall from placebo) was 8, 19, and 28% for single doses of 250 micrograms FP, 500 micrograms FP and 1000 micrograms FP, respectively. A single dose of budesonide, 800 micrograms (via Turbuhaler), resulted in a 16% cortisol suppression. The cortisol suppression for all three single doses of FP, and for the single dose of budesonide, was statistically significantly different from placebo. 3. Repeated dosing of FP (1000 micrograms twice daily for 3.5 days) resulted in a more marked plasma cortisol suppression; a fall of 65% from placebo (AUC FP 1000 mg twice daily vs AUC placebo, P < 0.001). 4. In a well‐controlled study in healthy volunteers, inhaled FP, in therapeutic doses, was shown to exhibit systemic effects which appear to be more pronounced after repeated dosing.

Brain tissue from 9 severely demented patients cared for in psychiatric long-term wards and with records of stroke episodes, macroscopic signs of brain infarcts and with no clinical evidence of senile dementia of the Alzheimer type was investigated and compared with control material. The mean volume of the brain infarcts in this vascular dementia group was only 6.8 ml. Pronounced disturbances of the serotoninergic and cholingergic systems were found in subcortical and cortical grey matter. These widespread neurotransmitter changes can hardly be explained by the localized brain infarcts per se, but suggest the existence of another category of vascular dementia. Since the neurotransmitter disturbances were found to be similar to those of Alzheimer's disease and senile dementia of the Alzheimer type, it seems more likely that they indicate a common pathway for dementia disorders than that they serve as markers of different dementia categories.

In vitro nomifensine demonstrates high affinity and specificity for dopamine reuptake sites in the brain. In the present study 11C-nomifensine was administered i.v. in trace amounts (10-50 micrograms) to ketamine anaesthetized Rhesus monkeys (6-10 kg b.w.) and the time-course of radioactivity within different brain regions was measured by positron emission tomography (PET). Six base-line experiments lasting for 60-80 min were performed. The procedure was repeated after pretreatment with nomifensine (2-6 mg/kg i.v.), another reuptake inhibitor, mazindol (0.3 mg/kg i.v.), desipramine (0.5 mg/kg i.v) or spiperone (0.3 mg/kg i.v.) before the administration of a second 11C-nomifensine dose. The highest radioactivity uptake was found in the dopamine innervated striatum and the lowest in a region containing the cerebellum, known to be almost devoid of dopaminergic neurons. The difference between striatal and cerebellar uptake of 11C-nomifensine derived radioactivity was markedly reduced after nomifensine and mazindol but not after desipramine and spiperone. These results indicate that in vivo the striatal uptake of 11C-nomifensine, as measured with PET, involves specific binding with the dopamine reuptake sites. In the first human applications of 11C-nomifensine and PET in a healthy volunteer, the regional uptake of radioactivity was similar to that in base-line experiments with Rhesus monkeys. In the healthy subject the striatal/cerebellar ratio was 1.6, 50 min after the injection of 11C-nomifensine. In a hemi-parkinsonian patient this ratio was 1.1 contralaterally and 1.3 ipsilaterally to the affected side. 11C-nomifensine and PET seems to be an auspicious method to measure the striatal dopaminergic nerve terminals of man in vivo.