- Email: [email protected]
Cyclophosphamide in the male rat: cerebral biochemical changes in progeny
Cyclop~osp~ami
e in the male rat: cerebral in progeny
ica
ges
MR Auroux’, EM Dulioust’, NY Naw&, SG Yacoub’, El3 Kempfj, AB Ebe13 ‘Laborafoire de Biologic de la Reproduction et du D+eloppemenf, CHLI BicJfre, 94275 Kremlin Bic&e, France; ‘Labora fury of Anatomy and Embryololpy. Faculty of Medicine, Ain-Shnms University. Cairo. Egypt; 3Ccnfre de Neurochimie. CNRS. 67084 Sfrasbourg, France (Received 8 August 1990; accepted 22 October 1990)
Summary - Adult male Wistar rats wcrc treated with cyclophosphamide either alone or with both cyclophosphamide and vinblastinc. They were then mated with virgin non-treated females. Examination of their offspring showed an increased post-natal mortality rate; and diminished learning capacity and spontaneous activity in the adults. These disorders were also found in the second generation, resulting from mating between animals of the first gcncration Biochemical analyses of the brains of the offspring of trcatci! males in the first and second generations showed a ~rnini~~ activity of hip~~rnp~ choline acctyl-tmnsf~ras~. Moreover, the second g~emti~ showed a diminution of fronto-parict~ cortex nor~pinephr~e.
These biochcmic~ results may correspond to the observed ~haviora1 deficits. Fu~he~or~, tation, they add to our knowledge of the consequences of certain cytostatic treatments.
by studying experimental mu-
cyclophospbamide I male rate mutation I progeny abnormality R&sum&- Cyclophosphamide chez le rat male: altkrations biochimiques c&&brales chez la prog&niture. Des ruts males adulfes Wisfar ont e’tC trait& suit avec du cyclophosphamique suit avec une association cyclophosphamide-vinblostine. 11s ont Pft: ensuite croist% avec des fenrclies vierges non traitPes. Leur proge’niture a montrk une augmentation du faux dc morfalitlf postnatale; une diminution, chcz lcs adultes. des capacitb d’apprentissage et de I’activitt spontanb. Ces anomalies onf if6 retrouvkes dnns lu sc:onde gPn&ation rPsultant du croisement des animaux de la premi+re gdn&aticm. L’Ptude biochimique du cerveau des rats issus des mciles trait& montre, darts la pretni&e et la secondc gkkafion. une di~~t~~tiott de L’activitd de la choline a&y1 fransf&ase ltippocantpique. En oufrc, la seconde &&afion r&C;le me chute du taux de la aor~pin~phrine du corfcx fronts-pa~~tul. Ces r&ultats pourraient b~o~~tindque~erlf corrcspondre G&Sdpficirs ~ontporten~~tta~ observes. Ils appartent par ail~eurs quelques &+nenfs nouveau quanf aux consequences possibles de certaks traite~lle~t~ ~ytostutiques. cyciopltosphamide
I mutation cltez le rat mfile I anomalies chez la progt?niture
Introduction The lesions caused by cyclopbosphamide in the DNA of the germ cells may result in mutations [ZZ]. Previous studies have shoym that first and second generations of male rats treated with this alkylating agent presented tmnsmissible bchavioral deficits [l, 4-61. Furthermore, several studies have revealed: the importanFe of genetic factors in learning processes [7, 231; the existence of relations between memory and cholincrgic sys-
tems, particularly in the hippocampus I$, 9, 201. and noradrenergic systems, especially in the fronto-parietnl zone [2, 15, 271; the existence of genetic control on ~holinergic Ill, 121 and noradrenergie [IS, 161 systems. These biochemical factors were investigated to detect possible changes accompanying the mutagenic behavioral alterations previously observed in the Fl and F2 progeny of FO cyclophosphamide-treated male rats [5, 61.
af anterior brain NE in ~EBX&I~ is controversMf, Some authors have indicated that NE facilitates acquisition [2], while others have found an o~~s~te effect [27] or have failed tu observe such an effect, but have observed that ME for@ brain deletion produced Fers~ve~t~~~ extinction of b;prning [19]_ However, as Kempf ~78ai US] have remarked, these studies are based an the action of ~h~aeolo~~~~ agents or art the result of cerebral lesions, bath are usually a matter of debate* For these au&ors, correlations between cere%d b~~hern~e~ factors and adding capacities sxr‘enot refiabte U&W the stud& 85~car&d out in genetically different animals, In this eontext, studies invalvi~g 2 strains of consanguineous mice and thezr ~cornbi~~ offspring showed that in ~irn~s with high adding perf-wee, the level md turnover d cortical 5% Timrule
were lowered. Our approach, which e&tides possible artefacts caused by direct interventiWI in the brain but uses genetic &eration, leads, how= ever, to the opposite result. of course, 0~3 may wonder sheer this &spar&~ resI3Bsfmm si@ifica@ &ff&er&cesbetweezEthe 2 models si i), consanguineous mice and ~~~-cons~n~~~~~Q~s rats are userXf;Irxdii), the modes of learning capac* ity explowtiion are not exa; By the same in both cases: mean number of avrtridance reaction& in a sh~~~x for mice, 6 ~eq~ successes with&z sil at%emptsin 3%s~~tt~~~x for rhe rat* From th& point of view, it would be inter@&@ to apply our protocol to the mice utilized by‘ Kempf et WJI[15]. How~vor, it seems that il genomic va&tion, whether &tlracterizing a &train or resu&~mgfrom ex~e~rne~t~ rnuta~~* nrighg lead zo ~~~~~~ in the Wei& NE in the zmtetior brain and to variations in IeWzing ~a~a~~ti~~
The observed WXII&%Zwere SE@ ia ~rn~~~ soH with %ose obtined by o&er methods- F63rexampfe, concerning CAT* differences related t& learning capacity were mom distinct in a previous study than In this one, but they were in mlation to 2 different mice strains [Uj and not to muta~ tion wi&im the same rat s&&n. Eeiatzng to NE&Areher c;t 8a$f3j using NE WW* rofoxins have report& shuttle avoidance deficit with 8%90% depletion of h@zcampus - cortex NE. However, it is evZent tilat rhe method used was far mom: diiect and drastic than ours. Moreox& we t&o&d note && some ~O~~~i~~~
as cyGlophosphamidP: might result in learning defi&rrcy in the progeny 15, 61, together with decrased levels of certain cerebrJxl biochemical factors such as hippocampal CAT activity or ~nt~-~~~ c%3&& NE The ~~~S~~~ of the bebWiu~al and ~~~~~a~ zWXBXiE=might argus fat a mu&g&c origin of these disorders. From this point of view, it is int@rrsstingto note that Banetic modification does not manifest itself as a qualitative all-or-nothing phenomenon- but q~~at~ve~y~ in a veq subtie way, by big the feveI of oert& rnedi%o= or the a&&g of cer&Gnenzymes. This evokes the va&tions that have been observed Wween straita& and also recallsl the research of Sinet et al [ZSJ who have shown a positive carrelation, in Down’s syndraw between g~u~~~i~e perotidztse a&iv& in red blood ceffs artd IQ* ?‘I.& qu~~~~~ve aspeg& which is well known for several enzymes has, howeve& not been sufficiently studied in the case of mutagenesis where it is currently easier to evaluatu the frequency uf qualitative changes. Emilty, these rest&s suggest fii% of all &e extreme ~g~~ty of the gene and the ~~~~~~yof the possible disturbances resulting Bronx mutations; secondly, by means of experimental mutagenesis, they agree with the known relations; between CA?.‘” NE and learning capacities. and thirdly, they introduce an additional elernenz to QUAknowledge of &e ankles af %Wtaia ~~tost~~ &eat= men&However, rnam woe is needed to determine the Qxtent of the eEf~.~sof such an experimental treatW?nt,
d=dM in mm slzsm* as in &e psz%si~ m&y* Tn0i-eOr fP;sSSlight kain biogenic amine efr;xffges
associated with func:Ional arbrxarmal%cs.This is the case in certain hereditary diseases inEluding different d@#rees of mental: deficiency such as LescLNyhan [I?] or Zett [ZS] syndromes, Similar ~~~rn~~~ anomalies &iv;3even been &W%d in cert&n St&&iof minor f~miliai cerebr& dysw functions such as familial attention deficit disw order 1241. Thus, experhnentally induced mutations in animals might slhcw similaritias with such mutati@as s~~~u~eous~y xcurring in man,
Tho authors thank Mrs Sherrer, Mrs $r;bccEzlndMiss Bouliicry for their tcchniical;Lssistanceand Mts Cepisul, Mrs &iuaisc,Mrs Rcirrmnnand Miss M&ngw-ray for ~~t~~~ assistance. This we& was suppw&d by granls imm ~~~~~~~~ pour fa Rec&-z&restil b Cantor {ARC Na 6 40g), i’fnstitut ~~t~u~~ de ia Santts ct dc Xrr Rccherchc MCdicale(PRC Na 1% 003) and Ia Direction dc la Rcchwhc du MinistErcdc l’$ducation Nalionizlc (Volct IntcrrratioaalDR/AP Na 85121).
Cyclophosp~mide and Neurobehaviorai Deficir. Alan Liss Inc, NY, 149 2 Anlezark GM, Crow TJ, Greenay AP (1973) Impaired learning and decreased cortical norephinephrine after bilateral locus coeruleus lesions. Science 181, 682 3 Archer T, Ogren SO, Johansson G, Ross SB (1982) DSP-4 induced two-way active avoidance impairment in rats: involvement of central and not peripheral noradrenaline depletion. Psychopharmacology 76, 303 4 Auroux M, Dulioust E (1985) Cy~loph~ph~ide in the male rat: behavioral effects in the adult offspring. Behav Brain Res 16, 25 5 Auroux M, Dulioust EM, Nawar NY, Yacoub G (1986) Antimitotic drugs (cyclophosphamide and vinblastine) in the male rat: deaths and behavioral abno~~i~es in the offspring. f Angle 7,378 6 Auroux MR, Dulioust EM, Nawar NY, Yacoub SG, Mayaux MJ, Schwartz D. David G (1988) Antimitotic drugs in the male rat: deaths and behavioral troubles in the second generation. J Androl 9, 153 7 Bovet D, Bovet-Nitti F, Oliverio A (1969) Genetic aspect of learning and memory in mice. Science 163, 139 8 De Feudis FV (1974) Cholinergic roles in motivated behaviours, emotion, learning and memory. In: Central Cholinergic System and Behaviour. Academic Press, NY, 75 9 Deutsch JA (1971) The cholinergic synapse and the site of the memos. Science 174, 788 10 Durkin T, Ayad G, Ebel E, Mandel P (1977) Regional acetylcholine turnover rate in the brains of three inbred strains of mice: correlation with some interstrain behavioural differences. Brain Res 136, 475 11 Ebel A, Hermetet JC, Mandel P (1973) Compar~ive study of acetylcholine esterase and choline acetyltransferase enzyme in brain of DBA and C57 mice. Nature New Biol 242, 56 12 Ebel A, Jaffard R, Destrade C, Ghazy A, Mandel P, Cardo B (1976) Modifications des mecanismes chol~~giques et de l’apprentissage chez trois lign&s de souris ~onsanguines par stimulation electrique del’hippocampe dorsal. Cr Acad Sci (Paris) 283 D, 535 13 Golberg AM, Kaita AA, MC Caman RE (1969) Microdetermination of choline acetyltransferase. A comparison of Reinecke vs periodide precipitation. J Neuruchem 16. 823
in the male rat
523
14 Jaffard R, Destrade C, Durkin T, I%& A (1979) Memory formation as related to genotypic or experimental variations of hippocampal choliirpjc activity in mice, Physiol Be&w 22, 1093 15 Kempf E, Gill M, Mack G, Mandel P (1978) Re~UvelIement de la noradrenaline dans diverses zones du syst&me nerveux central de souches consaguines de souris et de leurs recombinants. Cr Acad Sci (Paris) 286 D, 1161 16 Kempf E, Greisamer J, Mack G, Mat&l P (1974) Correlation of behavioral differences in three strains of mice with differences in brain amines. Ntiwe 247,483 I7 Liooyd KG, Homykiewicz 0, Davidson L, Shatmak K, Farley I, Goldstein M, Shibuya M, Kelley WN, Fox III (1981) Biochemical evidence of dysfunction of brain neurotransmitters in the Leseh-Nyhan syndrome. N Engl J Med 305, 1106 18 Lowry OH, Rosebrough NJ, Farr AL, Randall RL (1951) Protein measurement with the folin phenol reagent. J Biol Chem 93, 265 19 Mason ST, Iversen SD (1975) Learning in the absence of forebrain noradrenaline. Nature 248. 422 20 Matthies H (1974) The bi~hemi~ basis of learning and memory. Life Sci 15, 2917 21 MC Caman RE, Hunt JM (1965) Microdetermination of choline acetyltmnsferase in nervous tissue. J Neurochem 12, 253 22 Mirkes PE (1985) Cyclophosphamide teratogenesis: a review. Terufog Carcinog Mutagen 5, 75 23 Royce JR, Covington M (1960) Genetic differences in the avoidance conditioning in mice. J Camp Physiol Psycho1 53, 197 24 Shaywitz BA, Cohen DJ, Bowers MB Jr (1977) CSF monoamine metabolites in children with miniial brain dysfunction: evidence for alteration of brain dopamine. J Pediatr 90, 67 25 Sinet PM, Lejeune J, Jerome H (1979) Trisomy 21 (Down’s syndrome) glutathione peroxydase, hexose monophosphatase shunt and I.Q. Life Sri 24, 29 26 Singer B, Kusmierek JT (1982) Chemical mutagenesis. Ann Rev B&hem 52, 655 27 Wooley DW, Van der Hoeven TH (1963) Alteration in learning ability caused by changes in cerebral serotonin and catecholamines. Science 139, 610 28 Zoghbi HY, Percy AK, Glaze DG,, Butler II, Riccardi VM (1985) Reduction of biogenic amine levels in the Rett syndrome. New Engl J Med 313, 921
e in the male rat: cerebral in progeny
ica
ges
MR Auroux’, EM Dulioust’, NY Naw&, SG Yacoub’, El3 Kempfj, AB Ebe13 ‘Laborafoire de Biologic de la Reproduction et du D+eloppemenf, CHLI BicJfre, 94275 Kremlin Bic&e, France; ‘Labora fury of Anatomy and Embryololpy. Faculty of Medicine, Ain-Shnms University. Cairo. Egypt; 3Ccnfre de Neurochimie. CNRS. 67084 Sfrasbourg, France (Received 8 August 1990; accepted 22 October 1990)
Summary - Adult male Wistar rats wcrc treated with cyclophosphamide either alone or with both cyclophosphamide and vinblastinc. They were then mated with virgin non-treated females. Examination of their offspring showed an increased post-natal mortality rate; and diminished learning capacity and spontaneous activity in the adults. These disorders were also found in the second generation, resulting from mating between animals of the first gcncration Biochemical analyses of the brains of the offspring of trcatci! males in the first and second generations showed a ~rnini~~ activity of hip~~rnp~ choline acctyl-tmnsf~ras~. Moreover, the second g~emti~ showed a diminution of fronto-parict~ cortex nor~pinephr~e.
These biochcmic~ results may correspond to the observed ~haviora1 deficits. Fu~he~or~, tation, they add to our knowledge of the consequences of certain cytostatic treatments.
by studying experimental mu-
cyclophospbamide I male rate mutation I progeny abnormality R&sum&- Cyclophosphamide chez le rat male: altkrations biochimiques c&&brales chez la prog&niture. Des ruts males adulfes Wisfar ont e’tC trait& suit avec du cyclophosphamique suit avec une association cyclophosphamide-vinblostine. 11s ont Pft: ensuite croist% avec des fenrclies vierges non traitPes. Leur proge’niture a montrk une augmentation du faux dc morfalitlf postnatale; une diminution, chcz lcs adultes. des capacitb d’apprentissage et de I’activitt spontanb. Ces anomalies onf if6 retrouvkes dnns lu sc:onde gPn&ation rPsultant du croisement des animaux de la premi+re gdn&aticm. L’Ptude biochimique du cerveau des rats issus des mciles trait& montre, darts la pretni&e et la secondc gkkafion. une di~~t~~tiott de L’activitd de la choline a&y1 fransf&ase ltippocantpique. En oufrc, la seconde &&afion r&C;le me chute du taux de la aor~pin~phrine du corfcx fronts-pa~~tul. Ces r&ultats pourraient b~o~~tindque~erlf corrcspondre G&Sdpficirs ~ontporten~~tta~ observes. Ils appartent par ail~eurs quelques &+nenfs nouveau quanf aux consequences possibles de certaks traite~lle~t~ ~ytostutiques. cyciopltosphamide
I mutation cltez le rat mfile I anomalies chez la progt?niture
Introduction The lesions caused by cyclopbosphamide in the DNA of the germ cells may result in mutations [ZZ]. Previous studies have shoym that first and second generations of male rats treated with this alkylating agent presented tmnsmissible bchavioral deficits [l, 4-61. Furthermore, several studies have revealed: the importanFe of genetic factors in learning processes [7, 231; the existence of relations between memory and cholincrgic sys-
tems, particularly in the hippocampus I$, 9, 201. and noradrenergic systems, especially in the fronto-parietnl zone [2, 15, 271; the existence of genetic control on ~holinergic Ill, 121 and noradrenergie [IS, 161 systems. These biochemical factors were investigated to detect possible changes accompanying the mutagenic behavioral alterations previously observed in the Fl and F2 progeny of FO cyclophosphamide-treated male rats [5, 61.
af anterior brain NE in ~EBX&I~ is controversMf, Some authors have indicated that NE facilitates acquisition [2], while others have found an o~~s~te effect [27] or have failed tu observe such an effect, but have observed that ME for@ brain deletion produced Fers~ve~t~~~ extinction of b;prning [19]_ However, as Kempf ~78ai US] have remarked, these studies are based an the action of ~h~aeolo~~~~ agents or art the result of cerebral lesions, bath are usually a matter of debate* For these au&ors, correlations between cere%d b~~hern~e~ factors and adding capacities sxr‘enot refiabte U&W the stud& 85~car&d out in genetically different animals, In this eontext, studies invalvi~g 2 strains of consanguineous mice and thezr ~cornbi~~ offspring showed that in ~irn~s with high adding perf-wee, the level md turnover d cortical 5% Timrule
were lowered. Our approach, which e&tides possible artefacts caused by direct interventiWI in the brain but uses genetic &eration, leads, how= ever, to the opposite result. of course, 0~3 may wonder sheer this &spar&~ resI3Bsfmm si@ifica@ &ff&er&cesbetweezEthe 2 models si i), consanguineous mice and ~~~-cons~n~~~~~Q~s rats are userXf;Irxdii), the modes of learning capac* ity explowtiion are not exa; By the same in both cases: mean number of avrtridance reaction& in a sh~~~x for mice, 6 ~eq~ successes with&z sil at%emptsin 3%s~~tt~~~x for rhe rat* From th& point of view, it would be inter@&@ to apply our protocol to the mice utilized by‘ Kempf et WJI[15]. How~vor, it seems that il genomic va&tion, whether &tlracterizing a &train or resu&~mgfrom ex~e~rne~t~ rnuta~~* nrighg lead zo ~~~~~~ in the Wei& NE in the zmtetior brain and to variations in IeWzing ~a~a~~ti~~
The observed WXII&%Zwere SE@ ia ~rn~~~ soH with %ose obtined by o&er methods- F63rexampfe, concerning CAT* differences related t& learning capacity were mom distinct in a previous study than In this one, but they were in mlation to 2 different mice strains [Uj and not to muta~ tion wi&im the same rat s&&n. Eeiatzng to NE&Areher c;t 8a$f3j using NE WW* rofoxins have report& shuttle avoidance deficit with 8%90% depletion of h@zcampus - cortex NE. However, it is evZent tilat rhe method used was far mom: diiect and drastic than ours. Moreox& we t&o&d note && some ~O~~~i~~~
as cyGlophosphamidP: might result in learning defi&rrcy in the progeny 15, 61, together with decrased levels of certain cerebrJxl biochemical factors such as hippocampal CAT activity or ~nt~-~~~ c%3&& NE The ~~~S~~~ of the bebWiu~al and ~~~~~a~ zWXBXiE=might argus fat a mu&g&c origin of these disorders. From this point of view, it is int@rrsstingto note that Banetic modification does not manifest itself as a qualitative all-or-nothing phenomenon- but q~~at~ve~y~ in a veq subtie way, by big the feveI of oert& rnedi%o= or the a&&g of cer&Gnenzymes. This evokes the va&tions that have been observed Wween straita& and also recallsl the research of Sinet et al [ZSJ who have shown a positive carrelation, in Down’s syndraw between g~u~~~i~e perotidztse a&iv& in red blood ceffs artd IQ* ?‘I.& qu~~~~~ve aspeg& which is well known for several enzymes has, howeve& not been sufficiently studied in the case of mutagenesis where it is currently easier to evaluatu the frequency uf qualitative changes. Emilty, these rest&s suggest fii% of all &e extreme ~g~~ty of the gene and the ~~~~~~yof the possible disturbances resulting Bronx mutations; secondly, by means of experimental mutagenesis, they agree with the known relations; between CA?.‘” NE and learning capacities. and thirdly, they introduce an additional elernenz to QUAknowledge of &e ankles af %Wtaia ~~tost~~ &eat= men&However, rnam woe is needed to determine the Qxtent of the eEf~.~sof such an experimental treatW?nt,
d=dM in mm slzsm* as in &e psz%si~ m&y* Tn0i-eOr fP;sSSlight kain biogenic amine efr;xffges
associated with func:Ional arbrxarmal%cs.This is the case in certain hereditary diseases inEluding different d@#rees of mental: deficiency such as LescLNyhan [I?] or Zett [ZS] syndromes, Similar ~~~rn~~~ anomalies &iv;3even been &W%d in cert&n St&&iof minor f~miliai cerebr& dysw functions such as familial attention deficit disw order 1241. Thus, experhnentally induced mutations in animals might slhcw similaritias with such mutati@as s~~~u~eous~y xcurring in man,
Tho authors thank Mrs Sherrer, Mrs $r;bccEzlndMiss Bouliicry for their tcchniical;Lssistanceand Mts Cepisul, Mrs &iuaisc,Mrs Rcirrmnnand Miss M&ngw-ray for ~~t~~~ assistance. This we& was suppw&d by granls imm ~~~~~~~~ pour fa Rec&-z&restil b Cantor {ARC Na 6 40g), i’fnstitut ~~t~u~~ de ia Santts ct dc Xrr Rccherchc MCdicale(PRC Na 1% 003) and Ia Direction dc la Rcchwhc du MinistErcdc l’$ducation Nalionizlc (Volct IntcrrratioaalDR/AP Na 85121).
Cyclophosp~mide and Neurobehaviorai Deficir. Alan Liss Inc, NY, 149 2 Anlezark GM, Crow TJ, Greenay AP (1973) Impaired learning and decreased cortical norephinephrine after bilateral locus coeruleus lesions. Science 181, 682 3 Archer T, Ogren SO, Johansson G, Ross SB (1982) DSP-4 induced two-way active avoidance impairment in rats: involvement of central and not peripheral noradrenaline depletion. Psychopharmacology 76, 303 4 Auroux M, Dulioust E (1985) Cy~loph~ph~ide in the male rat: behavioral effects in the adult offspring. Behav Brain Res 16, 25 5 Auroux M, Dulioust EM, Nawar NY, Yacoub G (1986) Antimitotic drugs (cyclophosphamide and vinblastine) in the male rat: deaths and behavioral abno~~i~es in the offspring. f Angle 7,378 6 Auroux MR, Dulioust EM, Nawar NY, Yacoub SG, Mayaux MJ, Schwartz D. David G (1988) Antimitotic drugs in the male rat: deaths and behavioral troubles in the second generation. J Androl 9, 153 7 Bovet D, Bovet-Nitti F, Oliverio A (1969) Genetic aspect of learning and memory in mice. Science 163, 139 8 De Feudis FV (1974) Cholinergic roles in motivated behaviours, emotion, learning and memory. In: Central Cholinergic System and Behaviour. Academic Press, NY, 75 9 Deutsch JA (1971) The cholinergic synapse and the site of the memos. Science 174, 788 10 Durkin T, Ayad G, Ebel E, Mandel P (1977) Regional acetylcholine turnover rate in the brains of three inbred strains of mice: correlation with some interstrain behavioural differences. Brain Res 136, 475 11 Ebel A, Hermetet JC, Mandel P (1973) Compar~ive study of acetylcholine esterase and choline acetyltransferase enzyme in brain of DBA and C57 mice. Nature New Biol 242, 56 12 Ebel A, Jaffard R, Destrade C, Ghazy A, Mandel P, Cardo B (1976) Modifications des mecanismes chol~~giques et de l’apprentissage chez trois lign&s de souris ~onsanguines par stimulation electrique del’hippocampe dorsal. Cr Acad Sci (Paris) 283 D, 535 13 Golberg AM, Kaita AA, MC Caman RE (1969) Microdetermination of choline acetyltransferase. A comparison of Reinecke vs periodide precipitation. J Neuruchem 16. 823
in the male rat
523
14 Jaffard R, Destrade C, Durkin T, I%& A (1979) Memory formation as related to genotypic or experimental variations of hippocampal choliirpjc activity in mice, Physiol Be&w 22, 1093 15 Kempf E, Gill M, Mack G, Mandel P (1978) Re~UvelIement de la noradrenaline dans diverses zones du syst&me nerveux central de souches consaguines de souris et de leurs recombinants. Cr Acad Sci (Paris) 286 D, 1161 16 Kempf E, Greisamer J, Mack G, Mat&l P (1974) Correlation of behavioral differences in three strains of mice with differences in brain amines. Ntiwe 247,483 I7 Liooyd KG, Homykiewicz 0, Davidson L, Shatmak K, Farley I, Goldstein M, Shibuya M, Kelley WN, Fox III (1981) Biochemical evidence of dysfunction of brain neurotransmitters in the Leseh-Nyhan syndrome. N Engl J Med 305, 1106 18 Lowry OH, Rosebrough NJ, Farr AL, Randall RL (1951) Protein measurement with the folin phenol reagent. J Biol Chem 93, 265 19 Mason ST, Iversen SD (1975) Learning in the absence of forebrain noradrenaline. Nature 248. 422 20 Matthies H (1974) The bi~hemi~ basis of learning and memory. Life Sci 15, 2917 21 MC Caman RE, Hunt JM (1965) Microdetermination of choline acetyltmnsferase in nervous tissue. J Neurochem 12, 253 22 Mirkes PE (1985) Cyclophosphamide teratogenesis: a review. Terufog Carcinog Mutagen 5, 75 23 Royce JR, Covington M (1960) Genetic differences in the avoidance conditioning in mice. J Camp Physiol Psycho1 53, 197 24 Shaywitz BA, Cohen DJ, Bowers MB Jr (1977) CSF monoamine metabolites in children with miniial brain dysfunction: evidence for alteration of brain dopamine. J Pediatr 90, 67 25 Sinet PM, Lejeune J, Jerome H (1979) Trisomy 21 (Down’s syndrome) glutathione peroxydase, hexose monophosphatase shunt and I.Q. Life Sri 24, 29 26 Singer B, Kusmierek JT (1982) Chemical mutagenesis. Ann Rev B&hem 52, 655 27 Wooley DW, Van der Hoeven TH (1963) Alteration in learning ability caused by changes in cerebral serotonin and catecholamines. Science 139, 610 28 Zoghbi HY, Percy AK, Glaze DG,, Butler II, Riccardi VM (1985) Reduction of biogenic amine levels in the Rett syndrome. New Engl J Med 313, 921