CSF vasopressin and cyclic nucleotide concentrations in senile dementia

Psychoneuroendocrinology, Vol. 6, No.

2, pp. 171 - 176, 198 L

0306 - 4530/81/020171 - 06 $02.00/0 © 1981 Pergamon Press Ltd.

Printed in Great Britain.

CSF VASOPRESSIN AND CYCLIC NUCLEOTIDE CONCENTRATIONS IN SENILE DEMENTIA MOTOHIRO T S U J I , * SABURO TAKAHASHI* a n d SHIGENORI A K A Z A W A t *Department of Psychiatry, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu 520-21, Japan and tOzone Hospital, H~nan-cho Higashi 2-6-4, Toyonaka, Japan

(Received 3 December 1980) SUMMARY (1) Concentrations of vasopressin, cyclic AMP and cyclic GMP were determined in CSF from 16 patients with pre-senile and senile dementia. (2) CSF vasopressin concentrations in patients with dementia were 0.78 :t: 0.32 ~tU/ml (mean :t: S.D.), a significantly higher value than in control subjects (<0.5 ttU/ml). (3) CSF cyclic AMP concentrations showed no marked alteration, while concentrations of cyclic GMP were significantly elevated in these patients, as compared with those in control subjects. (4) These findings are suggestive of functional disturbances of vasopressin receptors present in the CNS in senile dementia, and cholinergic hyperactivity may also exist in this disorder.

Key Words--Senile dementia; vasopressin (ADH); cyclic AMP; cyclic GMP; receptor disease. INTRODUCTION

RECENTLY much attention has been paid to vasopressin (ADH), a neuropeptide hormone which is known not only to affect the consolidation phase of the memory process (de Wied, 1965, 1971), especially long term memory, but to be a neuromodulator (Tanaka, de Klot, de Wied & Versteeg, 1977; Kov~tcs, Bohus & Versteeg, 1979) which controls the activity of the central catecholaminergic system. Vasopressin is synthesized in cells of the anterior hypothalamus, in particular in the supraoptic and paraventricular nuclei. Axons from the supraoptic nuclei terminate in both the infundibular recess of the third ventricle and the paraventricular nuclei around the third ventricle. These morphological findings indicate that vasopressin may be secreted into cerebrospinal fluid (CSF) and play an important role in the process of memory consolidation (de Wied, Von Wimersma Greidanus, Bohus, Urban & Gispen, 1976). In accord with this hypothesis, it is reasonable to postulate a meaningful relation between vasopressin and memory disturbance in senile dementia. Changes in vasopressin concentrations have been seen in the CSF of patients with this disorder. Since recent evidence indicated that monoaminergic and cholinergic mechanisms also had effects on learning and memory, abnormalities in the concentrations of cyclic AMP and cyclic GMP may be present in the CSF of senile dementia. METHODS The subjects for this study were 16 inpatients, between the ages of 63 and 81, admitted either to the psychiatric ward at Shiga University Hospital, or to the Ozone Hospital in the vicinity. Although differentiation between degenerative dementia and cerebrovascular dementia is difficult without morphological findings, psychiatric symptoms of these patients met the diagnostic criteria of DSM-III, primary degenerative dementia, senile and pre-senile onset. We found l0 patients with senile dementia (290.00 - 290.30) 6 males and 4 females, between the 171

172

MOTOHIRO TSUJI, SABUROTAKAHASHIand SHIGENORI AKAZAWA

ages of 65 and 81 (70.7 _ 5.0, mean _ S.D.), and 6 patients with pre-senile dementia (290. 1)0, 5 males and a female, between the ages of 63 and 72 (66.7 _+ 3.8, mean _+ S.D.). Intellectual impairment of these patients was assessed by psychological testing using the WAIS. The control population, or the non-dementia group, selected from inpatients with various internal diseases, consisted o f 8 subjects, 7 males and a female, between the ages of 49 and 72 (62.6 ± 7.7, mean ± S.D.). All lumbar punctures were non-traumatic and were performed between 11:00 and 12:00 hr with patients in the left lateral decnbitus position. O f the first 5 ml of CSF collected, 4 ml were used for the determination of vasopressin concentrations. The assay employed was a modification of radioimmunoassay according to Skowsky, Rosenbloom & Fisher (1974), and Saito (1975) using A V P Grade VI (purchased from Sigma Chemical Co.) as standard and A D H free plasma. It permitted a detection level as low as 0.5 l~U/ml o f vasopressin with a 2.5 ml sample. Actual activity o f the standard preparation was 91%0 (the ratio o f B/Bo) for 50 x 2-' ~tU/ml ( m i n i m u m detectable levels), 80%0 for 50 x 2-~ I~U/ml. Interassay variation was 30% (coefficient o f variation) for concentrations less than 1.0 laU/ml, 25% for 1 . 0 - 5 . 0 IxU/ml. One ml CSF was transferred into a tube containing E D T A - N a 2 , immediately after lumbar puncture, and used for the measurement of cyclic A M P and cyclic G M P concentrations by radioimmunoassay ( H o n m a , Satoh, Takezawa & Ui, 1977). CSF samples were stored at - 2 0 ° C until assay which was performed within 7 days of the lumbar puncture.

RESULTS

CSF vasopressin concentrations in patients with pre-senile and senile dementia were 0.78 _+0.32 l~U/ml (mean __.S.D.). Of these 16 patients only three had values less than 0.5 ~tU/ml, while all those in the control group were less than 0.5 ixU/ml (see Table I). Because the method used to assay vasopressin had a sensitivity of 0.5 l~U/ml, it is not appropriate to compare the value for senile dementia, which is close to the limit of sensitivity, with that for the controls, which is within the limit, by Student's t-test. Therefore, the significance of difference in values between the two groups was calculated by the M a n n - Whitney U-test, and CSF concentrations of vasopressin in the dementia group were significantly higher than those in the control group (p<0.01) (Snedecor & Cochran, 1967). As shown in Fig. 1 correlation between the CSF concentration of vasopressin and age, with all data combined from both dementia and control groups, was not significant (r: 0.09, n.s.).

TABLE I. CSF VASOPRESSINCONCENTRATIONSIN PATIENTSWITH PRE-SENILE AND SENILE DEMENTIA ADH Pre-senile dementia (N = 6) Senile dementia (N = 10)

Control (N = 8)

Age

ADH

Age

ADH

Age

0.5 1.4

65 63

0.6, <0.5,

71 64

0.5, 1.1,

65 72

<0.5 0.5 0.8 0.9

65 81 73 73

1.4, 0.5, 0.7,

75 67 68

0.7, 0.6, <0.5,

69 71 67

<0.5 <0.5 <0.5

68 58 65

<0.5, <0.5, <0.5,

0.78 _+ 0.32* 70 56 72

A D H : ~tU/mi (laU = 2.5 pg). *Significantly different from controls p < 0.01 (Mann - Whitney U-test).

<0.5, <0.5,

66 49

<0.5

VASOPRESSIN AND NUCLEOTIDE CONCENTRATIONS IN SENILE DEMENTIA

@

I./-,

173

•

1.3 1.2

e---Dementia

o--=Control

1.1

~E ==

r:O.O9 (n.s)

1.0 0.9 0.8

r-t

0.7 41@

0.6 @

0.5 <05

o

0@

O0 i

5O

•

@~llO 0 0

6'0

7;

Age FIG. 1. Correlation between CSF vasopressin concentrations and age.

5O

~ zs

10

ooo .

o.

s

i

~ u

.~

:.=

0

0 Dementie Control

(n.s)

Dementio

Conlrol

(P~O.OO5. t-test)

FIG. 2. C S F cyclic nucleotide concentrations in patients with pre-senile and senile dementia.

Regarding the CSF concentrations of cyclic nucleotides, cyclic AMP concentrations in the dementia group showed no significant difference from those in the control group (see Fig. 2 left). In contrast, the concentrations of cyclic GMP in CSF in the dementia group were markedly and significantly higher than those in the control group (see Fig. 2 right). Correlation of the cyclic AMP concentrations with those of cyclic GMP was significant in the dementia group (r: 0.67, p < 0.01, solid circles in Fig. 3), while in the control subjects more highly significant correlation was observed (r: 0.95, p < 0.001, open circles in Fig. 3). With respect to the ratios of cyclic AMP to cyclic GMP concentrations, the dementia group showed significantly lower values (5.6 _+ 1.8) than those in the control group (13.2 ± 2.3) (p<0.001), Student's t-test (see Fig. 4). This difference resulted from close correlation between the values of cyclic AMP and cyclic GMP.

174

MOTOHIRO TSUJI, SABURO TAKAHASHIand SHIGENORIAKAZAWA

0--- Dementio

O---Control

a.

•

•

Y= 0.14X H.02 •0 r =0.67 ( P < O . O I ) ~~ .

(J

-~l

• 0 .,~2~ / I ~ Q " ~rO

0

0 / .--"J "

Y=O.11X-0.99 r =0.9S (p
20

40

Cyc [ic- AM P ( pmol e/ml )

FIG. 3. Correlation between cyclic AMP and cyclic GMP in CSF.

o oo

n

10

° o Oo

I.)

Dementia Control (P<:O.O01 ; t-test)

FiG. 4. CSF cyclic AMP/cyclic GMP ratio in patients with pre-senile and senile dementia.

DISCUSSION

Our study is evidence for the presence of elevated levels of CSF vasopressin in some patients with senile dementia. Vasopressin and its analogue are thought to affect the consolidation phase of the memory process. Experimental evidence for this is two fold: (1) removal of the posterior lobe of the pituitary interferes with the maintenance of a conditioned avoidance response, and (2) vasopressin, administered in amounts which normalize the water intake of mildly diabetic posterior lobectomized rats, restores the ability to maintain non-reinforced avoidance behavior. Rats with hereditary diabetes insipidus (Brattebeboro strain), which lack the ability to synthetize vasopressin, show inferior ability to acquire and maintain active and passive avoidance behavior. These behaviors are restored with the injection of vasopressin (Bohus, Van Wimersma Greidanus & de Wied, 1975). Thus, vasopressin is thought to be concerned with the phase of memory consolidation, and especially with the phase of long term memory (de Wied et al., 1976).

VASOPRESSIN AND NUCLEOTIDE CONCENTRATIONS IN SENILE DEMENTIA

175

Vasopressin, which is secreted into the CSF from supraoptic or paraventricular nuclei, is transported by CSF and may act on the receptors of midbrain limbic circuits, including septal and hippocampal structures (de Wied et al., 1976). However, valid evidence is lacking. Clinically, little evidence has been reported that vasopressin is related to memory. Studies on serum vasopressin concentrations in psychosis (Raskind, Weizman, Orenstein, Fisher & Courtney, 1978), and on vasopressin in amnesia (Blake, Dold & Grimley, 1978; Oliveros, Jandall, Timist-Berthier, Remy, Benghezal, Audibert & Moeglen, 1978) have been reported, but there has been no previous measurement of CSF vasopressin concentrations in senile dementia where memory is markedly disturbed. Although there is no proof that the vasopressin increase is due to a disturbance in its fixation to receptors, it can be hypothesized from our findings that vasopressin, released into CSF, may remain unbound in senile dementia, thus impairing memory consolidation. Vasopressin, when bound normally with receptors, may be metabolized rapidly, resulting in the low concentrations in CSF observed in the control group. Thus, functional disturbances in vasopressin receptors may exist in senile dementia. Although senile dementia has been widely accepted as a disorder caused by atrophy of the brain, a disparity has been observed between the clinical features and actual atrophy of the brain in some cases of dementia. There remain possibilities other than quantitative - morphological ones for the etiology of senile dementia, e.g. a qualitative change in receptor degeneration. Vasopressin receptors have been identified by using the immunocytochemical method (Catel, 1978), and vasopressin-containing neurons have also been reported which innervated intra- and extrahypothalamic structures, forming synapses with other neurons. (Buijs, Swaab, Dogterom & Van Leeuwen, 1978). We are not aware of any previous reports on the measurement of cyclic nucleotide concentrations in CSF in senile dementia. Since CSF cyclic GMP concentrations may reflect cholinergic activities in the central nervous system (McAfee, Schorseret & Greengard, 1971; Goldberg, O'Dea & Haddox, 1973), our results indicate that cholinergic mechanisms may also be disturbed in this disorder. Recent pharmacological research suggests that dysfunction in specific cholinergic mechanisms may be partically responsible for a decline in recent memory. For example, blockage of central cholinergic mechanisms with scopolamine induces amnesia in humans, but simultaneous administration of the anticholinesterase, physostigmine, reduces the scopolamine-induced amnesia (Bartus, 1979; Drachman, 1978). Also, brains of the aged showed a significant reduction in choline acetyltransferase activity (Scharrer, 1976). Studies using neurotransmitter binding techniques (QNB[H3]) revealed that cholinergic muscarine receptors were significantly damaged in Alzheimer's disease (Davies & Verth, 1978; Reisine, Yamamura & Bird, 1978). Therefore, our findings of elevated levels of cyclic GMP suggest a disturbance in acetylcholinergic neurons, especially cholinergic muscarine receptors, in senile dementia which manifests a clinical symptomatology of short memory disturbance.

REFERENCES BARTUS, R. T. (1979) Physostigmine and recent memory. Effects in young and aged n o n - h u m a n primitives. Science 26, 1087 - 1089. BLAKE, D. R., DOLD, M. J. & GRIMLEY, E. J. (1978) Vasopressin in amnesia. Lancet 15, 608.

176

MOTOHIRO TSUJI, SABUROTAKAHASHIand SHIGENORIAKAZAWA

BOHUS, B., VAN WIMERSMAGREIDANUS, TI. B. & DE W|ED, D. (1975) Behavioral and endocrine responses of rats with hereditary hypothalamic diabetes inspidus (Brattebeboro strain). Physiol. Behav. 14, 609- 615. Bu,JS, R, M., SWAAB, D. F., DOGTEROM, J. & VAN LEEUWEN, F. W. (1978) Intra- and extrahypothalamic vasopressin and oxytocin pathways in the rat. Cell. Tissue Res. 816, 423 -433. CATEL, M. (1978) Immunocytochemical evidence for vasopressin receptors. J. Histochem. Cytochem. 26, 581 - 592. DAVIES, P. & VERTH, A. H. (1978) Regional distribution of muscarine acetylcholine receptor in normal and AIzheimer's-typ¢ dementia brains. Brain Res. 138, 385 -392. DE WIED, D. (1965) The influence of the posterior and intermediate lobe of pituitary and pituitary-peptides on the maintenance o f a conditioned avoidance response in rats. Int. J. Neuropharmacol. 4, 1 5 7 - 167. DE WIED, D. (1971) Long term effect of vasopressin on the maintenance of a conditioned avoidance response in rats. Nature, Lond. 232, 58 - 60. DE WIED, D., VAN WIMERSMAGREIDANUS,TI. B., BOHUS, B., URBAN, I. • GISPEN, W. H. (1976) Vasopressin and memory consolidation. Prog. Brain Res. 45, 181 - 194. DRACHMAN, D. A. (1978) Memory and cognitive function in man: does the cholinergic system have a specific role? Neurology 27, 783 - 790. GOLDBERG, N. D., O'DEA, R. F. & HADDOX, M. V. (1973) In: Advances in Cyclic Nucleotide Research, P. Greengard and A. Robinson (Eds.), pp. 155 -223. Raven Press, New York. HONMA, M., SATOH, T., TAKEZAWA, J. & U1, M. (1977) An ultrasensitive method for the simultaneous determination of cyclic AMP and cyclic GMP in small-volume samples from blood and tissue. Biochem. Med. 18, 257 - 273. KovAcs, G. L., BOHUS, B. & VERSTEEG, D. H. G. (1979) The effect of vasopressin on memory processes: the role of noradrenergic neurotransmission. Biochem. Pharmacol. 28, 1529- 1537. McAFEE, D. A., SCHORSERET, M. & GREENGARD, P. (1971) Adenosine 3',5'-monophosphate in nervous tissue: increase associated with synaptic transmission. Science 171, 1156- 1158. OLIVEROS, J. C., JANDALL, M. K., TIMIST-BERTHIER, M., REMY, R., BENGHEZAL, A., AUDIBERT, A. ~g MOEGLEN, J. M. (1978) Vasopressin in amnesia. Lancet 7, 42. RASKIND, M. A., WEIZMANN, R. E., ORENSTEIN, H., FISHER, D. A. & COURTNEY, N. (1978) Is antidiuretic hormone elevated in psychosis? A pilot study. Biol. Psychiat. 13, 385 - 390. REISINE, T. D., YAMAMURA,H. 1. & BIRD, E. D. (1978) Pre- and postsynaptic neurochemical alternation in Alzheimer's disease. Brain Res. 159, 477-481. SAITO, T. (1975) Radioimmunoassay of arginine vasopressin and oxytocin. Saishin igaku 30, 726-731 (in Japanese). SCHARRER, B. (1976) Neurosecretion -comparative and evolutional aspects. Prog. Brain Res. 45, 125 - 137. SKOWSKY, W. R., ROSENBLOOM,A. A. & FISHER, O. A. (1974) Radioimmunoassay measurement of arginine vasopressin in serum development and application. J. clin. Endocr. Metab. 38, 278- 287. SNEDECOR, G. W. & COCHRAN, W. G. (1967) Statistical Methods, 6th Ed. Iowa State University Press, Iowa, U.S.A. TANAKA, M., DE KLOT, E. R., DE WIED, D. & VERSTEEG, D. H. G. (1977) Arginine'-vasopressin affects catecholamine metabolism in specific brain nuclei. Life Sci. 20, 1799- 1808.