1157 Discussion
single
The patients we studied had well-controlled or fairly well-controlled insulin-dependent diabetes with a mean frequency of 63% sugar-free urine tests done three times a day.13 They also fit the Joslin Clinic’s criteria with F.B.G. and P.P.B.G. means of 158±16 mg/dl and 123±16 mg/dl respectively.14 Our results demonstrate that in these patients HbAIC determined by the electrofocusing technique varies inversely with the quality of control as judged by the urinary glucose indices but not with blood-glucose levels or 24-hour glycosuria, even when repeated twice or more in 2 months; our findings are different from those of Gabbay et al. In fact, single bloodglucose levels were not representative of the degree of control as given by the HbAIC measurements or by urinary sugar indices. The HbAIC determination appears to be a far better method of measuring diabetes control than the usual criteria of fasting and postprandial blood-
sugars and 24-hour glycosuria IS and as effective as and more precise than three-times-a-day semiquantitative urinary sugar estimation. Of course, daily urine analyses remain the best way for the patient to estimate the quality of his own control. For the physician and the scientist, however, HbAIc is better since it requires only a
Preliminary Communication INCREASED BRAIN DOPAMINE AND REDUCED GLUTAMIC ACID DECARBOXYLASE AND CHOLINE ACETYL TRANSFERASE ACTIVITY IN SCHIZOPHRENIA AND RELATED PSYCHOSES ERNEST G. SPOKES ANGUS V. P. MACKAY MICHAEL SHEPHERD
EDWARD D. BIRD JOANNA BARNES LESLIE L. IVERSEN
M.R.C. Neurochemical Pharmacology Unit and Department of Neurological Surgery and Neurology, Addenbrooke’s Hospital, Cambridge; and Institute of Psychiatry, University
of London
Dopamine, glutamic acid decarboxylase (G.A.D.) and choline acetyltransferase in four regions of post-mortem were measured (C.A.T.) brains. 41 patients with the hospital diagnosis of schizophrenia (psychotic group) were compared with a control group (n=61). In the psychotic group, dopamine was 48% higher in the nucleus accumbens but normal in the putamen. G.A.D. activity was significantly reduced in the psychotic group, by about 50% in the nucleus accumbens, amygdala and hippocampus, and by about 30% in the putamen. C.A.T. activity was significantly lower in nucleus accumbens from the psychotic group, but normal in other brain regions. From an assessment of case notes, "schizophrenia" was distinguished from "schizophrenia-like psychosis". The biochemical findings for these subgroups were essentially similar, although C.A.T. activity in nucleus accumbens and hippocampus from the schizophrenic group was significantly lower than in controls. It is possible that increased dopamine and reduced G.A.D. and C.A.T.
Summary
activities in limbic
areas
of brain
are
associated with
schizophrenia and schizophrenia-like psychoses, although whether such neurochemical abnormalities are
measurement
and does
not
depend
on
patient
measurement, which may not always be reliable. We thank Prof. J. Rosa, U91 INSERM Hopital H. Mondor 94, Creteil, France, for criticism and advice, and Mrs A. Fenelon for technical assistance.
Requests Recherches
-
reprints should be addressed to E. E., Unite de Statistiques, INSERM, 16 bis, Avenue Paul-Vaillant-Coufor
tiirier- 94800 Villejuif. France. REFERENCES
Rahbar, S. Clin. chimica Acta, 1968, 22, 296. Rahbar, S., Blumenfeld, O., Ranney, H. M. Biochem. biophys. Res. Comm. 1969, 36, 838. 3. Trivelli, L. A., Ranney, H. M., Lai, H. New Engl. J. Med. 1971, 284, 353. 4. Paulsen, E. P. Metabolism, 1971, 22, 269. 5. Gabbay, K. H., Hasty, K., Breslow, J. L., Ellison, R. C., Bunn, H. F., Gallop, P. M. J. clin. Endocr. Metab. 1977, 44, 859. 6. Koenig, R. J., Peterson, C. M., Kilo, C., Cerami, A., Williamson, J. R. Diabetes, 1976, 25, 230. 7. Gabbay, K. H. New Engl. J. Med. 1976, 295, 443. 8. Koenig, R. J., Peterson, C. M., Jones, R. L., Saudek, C., Lehrman, M., Cerami, A. ibid. 1976, 295, 417. 9. Jeppsson, J. O. L. K. B Applications, note 307. Stockholm, 1977. 10. Knshnamoorthy, R., Wacjman, H., Labie, D. Clin. chimica Acta, 1976, 69, 1. 2.
203. 11.
Hanks, G. E., Cassel, M., Ray, R. N. Chaplin, H. J. Lab. clin. Med. 1960, 56, 486.
D. Méthodes statistiques à l’usage des médecins et biologistes; p. 256. Paris, 1963. 13. Malins, J. Clinical Diabetes Mellitus; p. 447. London, 1968. 14. Marble, A., White, P., Bradley, R. F., Krall, L. P. Joslin’s Diabetes Mellitus; 12.
Schwartz,
pp. 191, 255. Philadelphia, 1971. 15. Ricketts. H. T. in On the Nature and Treatment of Diabetes
(edited by B. S.
Leibel and G. A. Wrenshall); p. 588. Amsterdam, 1965.
to the illness or are a consequence of prolonged treatment with neuroleptic drugs remains unclear.
related
INTRODUCTION
No consistent neuropathological abnormality has been defined in schizophrenia, although various lines of evidence suggest that a disorder of the limbic system may be involved.’-’ Neuropharmacological studies have led to the hypothesis that drugs which are effective in treating the symptoms of schizophrenic illness act by antagonising the effects of the monoamine transmitter
dopamine at central-nervous-system receptors.6—8 Dopaminergic neuronal pathways innervate various areas of the mammalian limbic system, and this may be a key site for the antipsychotic actions of neuroleptic drugs9,10 and for a neurochemical abnormality underlying the disease. We have measured neurotransmitters and related enzymes in post-mortem brain samples from psychotic patients, an approach which has revealed neurochemical abnormalities in Parkinson’s disease" and Huntington’s chorea.12 Our preliminary findings indicate significant abnormalities in both acid (G.A. B.A.) systems.
dopamine
and
y-aminobutyric
MATERIALS AND METHODS
Brain Dissection Post-mortem brain tissue was collected as described previously,12 except that whole brains were frozen at -20°C shortly after necropsy. The mean time (±S.D.) between death and removal of the cadaver to a 4°C refrigerator in the control and psychotic groups was 1.7±0.5h and 3.0±1.8h, respectively. The mean interval from death to necropsy was 39±226 h in the control group and 41±25.8h in the psychotic group. The mean age at death in the control and psychotic group was 60±20 and 58+20 years respectively. There were 9 suicides in the psychotic group, 7 by patients under 40 years old. The causes of death in middle-aged and elderly patients were similar to those of the controls. Frozen brains were transported on dry ice, stored at -20°C and then at —10°C for 12 h before dissection. Each brain was
1158 sectioned anteroposteriorly into serial 3 mm thick coronal slices which were dissected at -5 °C. Since the nucleus accumbens cannot be demarcated macroscopically, it was defined as that part of the striatum lying rostral and ventral to the plane of the anterior commissure and medial to the anterior limb of the internal capsule.
Enzyme Methods Dopamine was measured by the method of Cuello et al. 13 The activity of glutamic acid decarboxylase (G.A.D.), an enzyme marker for neurones containing G.A.B.A., was measured by the method of Roberts and Simonsen)4 Choline acetyltransferase (C.A.T.) activity, an enzyme marker for cholinergic cells, was measured by the method of Fonnum.15 Protein was estimated by the method of Lowry et al. 16 There was no significant difference in the protein content of control and schizophrenic tissues. Tissues from psychotic cases (n=41) and control cases (n=61) were always assayed in parallel.
Clinical Data Post-mortem material was obtained from 41 patients (psychotic group) in whom a clinical diagnosis of schizophrenia had been made by one or more psychiatrists. After a patient’s death, two psychiatrists independently assessed the case notes and classed the case as "schizophrenia" or "schizophrenia-like psychosis". When there was disagreement, the decision of a referee (M.S.) was final. The main factors determining the diagnosis of schizophrenia were: (1) first psychiatric presentation under the age of 30; (2) a chronic illness with repeated hospital admissions or, as in many cases, uninterrupted hospital care after the first admission; (3) the core symptoms of schizophrenic illness as included in the nuclear syndrome of the Wing symptom check list," which roughly correspond to Schneider’s first-rank symptoms; and (4) the absence of significant organic illness or psychotogenic-drug abuse. 26 of the 41 patients in the psychotic group were diagnosed as schizophrenic. The 15 who were placed in the schizophrenia-like group ranged from those who narrowly failed to meet the criteria for schizophrenia, to those in whom the diagnosis of schizophrenia seemed inappropriate. Controls
Samples of post-mortem brain tissue for use as controls were provided by the department of pathology, Addenbrooke’s Hospital, Cambridge, from 61 patients who had died from accidental
or
natural
causes
other than disorders of the
tem. TABLE
I-DOPAMINE, G.A.D.,
nervous
sys-
Dopamine concentrations and G.A.D. and C.A.T. activities in the nucleus accumbens of control (e) and psychotic () postmortem brain. Mean represented as-. RESULTS
Four brain regions (nucleus accumbens, putamen, amygdala, and hippocampus) were examined. The activity of G.A.D. was lower in the psychotic patients than in controls (see figure and table I). G.A.D. activity in limbic areas was reduced by about 50%, with a smaller reduction (about 30%) in putamen. The cholinergic marker enzyme c.A.T. had normal activity in most brain regions except the nucleus accumbens, where there was a significant reduction (table I). There was no detectable mine in hippocampus and the concentrations in amygdala were too low to measure accurately. Dopamine in nucleus accumbens from psychotic patients was significantly raised, being approximately 50% higher than in controls whereas the dopamine in putamen from the same brains was normal (table I). The results for patients with schizophrenia and those with schizophrenia-like psychoses were very similar
dopa-
AND C.A.T. IN POST-MORTEM BRAIN FROM PSYCHOTIC PATIENTS AND CONTROLS
*=P
single
The patients we studied had well-controlled or fairly well-controlled insulin-dependent diabetes with a mean frequency of 63% sugar-free urine tests done three times a day.13 They also fit the Joslin Clinic’s criteria with F.B.G. and P.P.B.G. means of 158±16 mg/dl and 123±16 mg/dl respectively.14 Our results demonstrate that in these patients HbAIC determined by the electrofocusing technique varies inversely with the quality of control as judged by the urinary glucose indices but not with blood-glucose levels or 24-hour glycosuria, even when repeated twice or more in 2 months; our findings are different from those of Gabbay et al. In fact, single bloodglucose levels were not representative of the degree of control as given by the HbAIC measurements or by urinary sugar indices. The HbAIC determination appears to be a far better method of measuring diabetes control than the usual criteria of fasting and postprandial blood-
sugars and 24-hour glycosuria IS and as effective as and more precise than three-times-a-day semiquantitative urinary sugar estimation. Of course, daily urine analyses remain the best way for the patient to estimate the quality of his own control. For the physician and the scientist, however, HbAIc is better since it requires only a
Preliminary Communication INCREASED BRAIN DOPAMINE AND REDUCED GLUTAMIC ACID DECARBOXYLASE AND CHOLINE ACETYL TRANSFERASE ACTIVITY IN SCHIZOPHRENIA AND RELATED PSYCHOSES ERNEST G. SPOKES ANGUS V. P. MACKAY MICHAEL SHEPHERD
EDWARD D. BIRD JOANNA BARNES LESLIE L. IVERSEN
M.R.C. Neurochemical Pharmacology Unit and Department of Neurological Surgery and Neurology, Addenbrooke’s Hospital, Cambridge; and Institute of Psychiatry, University
of London
Dopamine, glutamic acid decarboxylase (G.A.D.) and choline acetyltransferase in four regions of post-mortem were measured (C.A.T.) brains. 41 patients with the hospital diagnosis of schizophrenia (psychotic group) were compared with a control group (n=61). In the psychotic group, dopamine was 48% higher in the nucleus accumbens but normal in the putamen. G.A.D. activity was significantly reduced in the psychotic group, by about 50% in the nucleus accumbens, amygdala and hippocampus, and by about 30% in the putamen. C.A.T. activity was significantly lower in nucleus accumbens from the psychotic group, but normal in other brain regions. From an assessment of case notes, "schizophrenia" was distinguished from "schizophrenia-like psychosis". The biochemical findings for these subgroups were essentially similar, although C.A.T. activity in nucleus accumbens and hippocampus from the schizophrenic group was significantly lower than in controls. It is possible that increased dopamine and reduced G.A.D. and C.A.T.
Summary
activities in limbic
areas
of brain
are
associated with
schizophrenia and schizophrenia-like psychoses, although whether such neurochemical abnormalities are
measurement
and does
not
depend
on
patient
measurement, which may not always be reliable. We thank Prof. J. Rosa, U91 INSERM Hopital H. Mondor 94, Creteil, France, for criticism and advice, and Mrs A. Fenelon for technical assistance.
Requests Recherches
-
reprints should be addressed to E. E., Unite de Statistiques, INSERM, 16 bis, Avenue Paul-Vaillant-Coufor
tiirier- 94800 Villejuif. France. REFERENCES
Rahbar, S. Clin. chimica Acta, 1968, 22, 296. Rahbar, S., Blumenfeld, O., Ranney, H. M. Biochem. biophys. Res. Comm. 1969, 36, 838. 3. Trivelli, L. A., Ranney, H. M., Lai, H. New Engl. J. Med. 1971, 284, 353. 4. Paulsen, E. P. Metabolism, 1971, 22, 269. 5. Gabbay, K. H., Hasty, K., Breslow, J. L., Ellison, R. C., Bunn, H. F., Gallop, P. M. J. clin. Endocr. Metab. 1977, 44, 859. 6. Koenig, R. J., Peterson, C. M., Kilo, C., Cerami, A., Williamson, J. R. Diabetes, 1976, 25, 230. 7. Gabbay, K. H. New Engl. J. Med. 1976, 295, 443. 8. Koenig, R. J., Peterson, C. M., Jones, R. L., Saudek, C., Lehrman, M., Cerami, A. ibid. 1976, 295, 417. 9. Jeppsson, J. O. L. K. B Applications, note 307. Stockholm, 1977. 10. Knshnamoorthy, R., Wacjman, H., Labie, D. Clin. chimica Acta, 1976, 69, 1. 2.
203. 11.
Hanks, G. E., Cassel, M., Ray, R. N. Chaplin, H. J. Lab. clin. Med. 1960, 56, 486.
D. Méthodes statistiques à l’usage des médecins et biologistes; p. 256. Paris, 1963. 13. Malins, J. Clinical Diabetes Mellitus; p. 447. London, 1968. 14. Marble, A., White, P., Bradley, R. F., Krall, L. P. Joslin’s Diabetes Mellitus; 12.
Schwartz,
pp. 191, 255. Philadelphia, 1971. 15. Ricketts. H. T. in On the Nature and Treatment of Diabetes
(edited by B. S.
Leibel and G. A. Wrenshall); p. 588. Amsterdam, 1965.
to the illness or are a consequence of prolonged treatment with neuroleptic drugs remains unclear.
related
INTRODUCTION
No consistent neuropathological abnormality has been defined in schizophrenia, although various lines of evidence suggest that a disorder of the limbic system may be involved.’-’ Neuropharmacological studies have led to the hypothesis that drugs which are effective in treating the symptoms of schizophrenic illness act by antagonising the effects of the monoamine transmitter
dopamine at central-nervous-system receptors.6—8 Dopaminergic neuronal pathways innervate various areas of the mammalian limbic system, and this may be a key site for the antipsychotic actions of neuroleptic drugs9,10 and for a neurochemical abnormality underlying the disease. We have measured neurotransmitters and related enzymes in post-mortem brain samples from psychotic patients, an approach which has revealed neurochemical abnormalities in Parkinson’s disease" and Huntington’s chorea.12 Our preliminary findings indicate significant abnormalities in both acid (G.A. B.A.) systems.
dopamine
and
y-aminobutyric
MATERIALS AND METHODS
Brain Dissection Post-mortem brain tissue was collected as described previously,12 except that whole brains were frozen at -20°C shortly after necropsy. The mean time (±S.D.) between death and removal of the cadaver to a 4°C refrigerator in the control and psychotic groups was 1.7±0.5h and 3.0±1.8h, respectively. The mean interval from death to necropsy was 39±226 h in the control group and 41±25.8h in the psychotic group. The mean age at death in the control and psychotic group was 60±20 and 58+20 years respectively. There were 9 suicides in the psychotic group, 7 by patients under 40 years old. The causes of death in middle-aged and elderly patients were similar to those of the controls. Frozen brains were transported on dry ice, stored at -20°C and then at —10°C for 12 h before dissection. Each brain was
1158 sectioned anteroposteriorly into serial 3 mm thick coronal slices which were dissected at -5 °C. Since the nucleus accumbens cannot be demarcated macroscopically, it was defined as that part of the striatum lying rostral and ventral to the plane of the anterior commissure and medial to the anterior limb of the internal capsule.
Enzyme Methods Dopamine was measured by the method of Cuello et al. 13 The activity of glutamic acid decarboxylase (G.A.D.), an enzyme marker for neurones containing G.A.B.A., was measured by the method of Roberts and Simonsen)4 Choline acetyltransferase (C.A.T.) activity, an enzyme marker for cholinergic cells, was measured by the method of Fonnum.15 Protein was estimated by the method of Lowry et al. 16 There was no significant difference in the protein content of control and schizophrenic tissues. Tissues from psychotic cases (n=41) and control cases (n=61) were always assayed in parallel.
Clinical Data Post-mortem material was obtained from 41 patients (psychotic group) in whom a clinical diagnosis of schizophrenia had been made by one or more psychiatrists. After a patient’s death, two psychiatrists independently assessed the case notes and classed the case as "schizophrenia" or "schizophrenia-like psychosis". When there was disagreement, the decision of a referee (M.S.) was final. The main factors determining the diagnosis of schizophrenia were: (1) first psychiatric presentation under the age of 30; (2) a chronic illness with repeated hospital admissions or, as in many cases, uninterrupted hospital care after the first admission; (3) the core symptoms of schizophrenic illness as included in the nuclear syndrome of the Wing symptom check list," which roughly correspond to Schneider’s first-rank symptoms; and (4) the absence of significant organic illness or psychotogenic-drug abuse. 26 of the 41 patients in the psychotic group were diagnosed as schizophrenic. The 15 who were placed in the schizophrenia-like group ranged from those who narrowly failed to meet the criteria for schizophrenia, to those in whom the diagnosis of schizophrenia seemed inappropriate. Controls
Samples of post-mortem brain tissue for use as controls were provided by the department of pathology, Addenbrooke’s Hospital, Cambridge, from 61 patients who had died from accidental
or
natural
causes
other than disorders of the
tem. TABLE
I-DOPAMINE, G.A.D.,
nervous
sys-
Dopamine concentrations and G.A.D. and C.A.T. activities in the nucleus accumbens of control (e) and psychotic () postmortem brain. Mean represented as-. RESULTS
Four brain regions (nucleus accumbens, putamen, amygdala, and hippocampus) were examined. The activity of G.A.D. was lower in the psychotic patients than in controls (see figure and table I). G.A.D. activity in limbic areas was reduced by about 50%, with a smaller reduction (about 30%) in putamen. The cholinergic marker enzyme c.A.T. had normal activity in most brain regions except the nucleus accumbens, where there was a significant reduction (table I). There was no detectable mine in hippocampus and the concentrations in amygdala were too low to measure accurately. Dopamine in nucleus accumbens from psychotic patients was significantly raised, being approximately 50% higher than in controls whereas the dopamine in putamen from the same brains was normal (table I). The results for patients with schizophrenia and those with schizophrenia-like psychoses were very similar
dopa-
AND C.A.T. IN POST-MORTEM BRAIN FROM PSYCHOTIC PATIENTS AND CONTROLS
*=P
