Effect of Pre- and Postnatal Manganese Exposure on Brain Histamine Content in a Rodent Model of Parkinson\u27s Disease

Rats lesioned shortly after birth with 6-hydroxydopamine (6-OHDA; 134 μg icv) represent a near-ideal model of severe Parkinson\u27s disease because of the near-total destruction of nigrostriatal dopaminergic fibers. There are scarce data that in Parkinson\u27s disease, activity of the central histaminergic system is increased. The element manganese, an essential cofactor for many enzymatic reactions, itself in toxic amount, replicates some clinical features similar to those of Parkinson\u27s disease. The aim of this study was to examine the effect of neonatal manganese exposure on 6-OHDA modeling of Parkinson\u27s disease in rats, and to determine effects on histamine content in the brain of these rats in adulthood. Manganese (MnCl 2•4H 2O; 10,000 ppm) was included in the drinking water of pregnant Wistar rats from the time of conception until the 21st day after delivery, the age when neonatal rats were weaned. Control rats consumed tap water. Other groups of neonatal rat pups, on the 3rd day after birth, were pretreated with desipramine (20 mg/kg ip 1 h) prior to bilateral icv administration of 6-OHDA (60 or 134 μg) or its vehicle saline-ascorbic (0.1%) (control). At 2 months after birth, in rats lesioned with 60 or 134 μg 6-OHDA, endogenous striatal dopamine (DA) content was reduced, respectively, by 92 and 98% (HPLC/ED), while co-exposure of these groups to perinatal manganese did not magnify the DA depletion. However, there was prominent enhancement of histamine content in frontal cortex, hippocampus, hypothalamus, and medulla oblongata of adult rat brain after 6-OHDA (60 and 134 μg) injection on the day 3rd postnatal day. These findings indicate that histamine and the central histaminergic system are altered in the brain of rats lesioned to model Parkinson\u27s disease, and that manganese enhances effects of 6-OHDA on histamine in brain

Effect of prenatal copper exposure on the central dopaminergic system in adult rats

BACKGROUND The effect of prenatal exposition of rats with copper on its level in the newborns’ organs and central dopaminergic system activity in adult rats was examined. MATERIAL AND METHODS Pregnant rats during entire time of pregnancy drank water with cupprum sulfuricum (CuSO4) where concentration of metal was 100 ppm. Control rats drank the water only without cuprum. After delivery water with metal was substituted with water only, and newborns stayed with their mothers till 21st day of life, then separated. In newborn copper content was estimated in the brain, liver and kidney. In adult rats the level of biogenic amines was measured in the brain and some behavioral studies were performed such as oral activity, stereotyped and yawning behavior, using central dopamine receptor agonists (SKF 38393, apomorphine, 7-OH-DPAT). RESULTS AND CONCLUSION Exposition of rats during intrauteral development (prenatal) with copper caused significant increase concentration examined metal in the brain, liver and kidney of newborn rats. In adult rats significant decrease of dopamine in the striatum was noticed in the rats pretreated with copper. Beside increase reactivity of the central dopamine D1 receptor reactivity was observed, and manifested by increased oral activity after SKF 38393 and stereotyped behavior after apomorphine apply. Additionally decreased reactivity of the central dopamine D3 receptor was manifested by decreased yawning behavior after 7-OH-DPAT injection. From above we concluded that copper can be one of the environmental agent which can affected of the central dopaminergic system in mammalians.WSTĘP Celem pracy było zbadanie wpływu ekspozycji miedzią szczurzyc w trakcie ciąży na zawartość metalu w tkankach noworodków a także na funkcję ośrodkowego układu dopaminergicznego u dorosłego potomstwa. MATERIAŁ I METODY Ciężarne samice przez cały okres ciąży piły wodę z dodatkiem siarczanu miedzi (CuSO4) w stężeniu metalu 100 ppm. Kontrolne szczurzyce piły wodę bez metalu. Z chwilą urodzenia roztwór miedzi zamieniano na wodę. Noworodki pozostawały z matkami do 21 dnia życia. U noworodków oznaczono zawartość miedzi w mózgu, wątrobie i nerkach. U dorosłych potomnych szczurów płci męskiej wykonano oznaczenia zawartości amin biogennych w mózgu oraz oceniono zachowanie jak aktywność ruchową pyska, stereotypię apomorfinową i liczbę ziewnięć, spontaniczną jak też po podaniu agonistów ośrodkowych receptorów dopaminowych (SKF 38393, apomorfi na, 7-OH-DPAT). WYNIKI I WNIOSKI Prenatalna ekspozycja szczurów miedzią spowodowała znaczny wzrost zawartości metalu w mózgu, wątrobie i nerkach w porównaniu z kontrolą. U dorosłych szczurów narażonych w okresie rozwoju śródmacicznego na miedź wykazano obniżenie zawartości dopaminy w prążkowiu oraz wzrost reaktywności receptorów dopaminowych D1 manifestujący się nasileniem aktywności ruchowej pyska po podaniu SKF 38393 i nasileniem zachowania stereotypowego po podaniu apomorfiny oraz obniżenie reaktywności receptorów dopaminowych D3 manifestujące się zmniejszeniem liczby ziewnięć po podaniu 7-OH-DPAT. Z powyższego wynika, że narażenia (ekspozycja) miedzią w okresie rozwoju śródmacicznego prowadzi do kumulacji metalu w tkankach noworodków a także trwałego zaburzenia funkcji ośrodkowego układu dopaminergicznego u ssaków

Wpływ chlorfeniraminy i cymetydyny, antagonistów receptorów histaminowych H1 i H2 na wychwyt (3H)glukozy w mózgu dorosłych szczurów po podaniu noworodkom 5,7-dihydroksytryptaminy

BACKGROUND The aim of the study was to examine eff ect of chlorpheniramine (hista- mine H1 receptor antagonist) and cimetidine (histamine H2 receptor an- tagonist) on (3H)glucose uptake in the brain of adult rats lesioned with 5,7-dihydroxytryptamine (neurotoxin for the central serotoninergic sys- tem) as neonates. MATERIAL AND METHODS Male 3-days old Wistar rats were injected with serotoninergic neurons neurotoxin 5,7-dihydroxytryptamine, 75 μg icv. Control rats were injected with saline 10 μg icv. At 8 weeks level of 5-HT and 5-HIAA was estimat- ed in the striatum, frontal cortex and hippocampus of the brain. Other 8 weeks old animals of control and 5,7-DHT lesioned as neonates were injected with S(+)chlorpheniramine (H1 receptor antagonist) 10.0 mg/kg ip or with cimetidine (H2 receptor antagonist) 5.0 mg/kg ip. Control rats were injected with saline 1.0 ml/kg ip. 60 minutes later 6-(3H)-D-glucose was applied in a dose of 500 μCi/kg ip and 15 minutes later all rats were decapitated and their brains were excised, placed on the ice and sample of frontal cortex, striatum, hippocampus, thalamus with hypothalamus, pons and cerebellum were separated and weighted. Then in the examined tissues radioactivity was measured in liquid scintillation counter and ex- pressed in DPM/100 mg of wet tissue. RESULTS 5,7-DHT decreased signifi cantly the level of 5-HT and 5-HIAA in all examined tissues in the brain of adult rats. In rats neonatally lesioned with 5,7-DHT radioactivity signifi cantly increased as compare to the control. Chlorpheniramine prevent signifi cantly that eff ect in the frontal cortex and cimetidine in the frontal cortex, hippocampus and cerebellum. CONCLUSION From above we conclude that in the brain of mammalians the metabolic link between histaminergic and serotoninergic system exist in regulation of energetic prcesses connected with glucose metabolism.WSTĘP Celem pracy było zbadanie wpływu chlorfeniraminy, antagonisty receptora histaminowego H1 i cymetydyny, antagonisty receptora histaminowego H2 na wychwyt (3H)glukozy w mózgu dorosłych szczurów z lezją (zniszczenie) ośrodkowego układu serotoninergicznego wywołaną podaniem noworodkom neurotoksyny 5,7-dihydroksytryptaminy. MATERIAŁ I METODY Trzydniowe noworodki płci męskiej szczepu Wistar otrzymały do bocznej komory mózgu (icv) 75 μg 5,7-dihydroksytryptaminy (5,7-DHT), neurotoksynę układu serotoninergicznego. Zwierzęta kontrolne otrzymały icv 10 μl 0,9% roztworu NaCl. Po osiągnięciu 8 tygodni życia zwierzęta dekapitowano i w korze czołowej, prążkowiu oraz zakręcie hipokampa oznaczono zawartość 5-HT i 5-HIAA metodą HPLC/ED. Osobnej grupie badanej i kontrolnej podano S(+)chlorfeniraminę 10,0 mg/kg ip (antagonista receptora histaminowego H1) lub cymetydynę 5,0 mg/kg ip (antagonista receptora histaminowego H2). Zwierzęta kontrolne obu grup otrzymały 0,9% roztwór NaCl 1,0 ml/kg ip. Po 60 minutach wszystkie szczury otrzymały 6-(3H)-D-glukozę 500 μCi/kg ip. Po dalszych 15 minutach zwierzęta dekapitowano, wyjmowano z czaszki mózg, separowano z niego korę czołową, prążkowie, hipokamp, wzgórze z podwzgórzem, most i móżdżek, w których oznaczono radioaktywność przy użyciu licznika scyntylacyjnego. Wyniki wyrażono w DPM (Desintegrations Per Minute) na 100 mg świeżej tkanki. WYNIKI 5,7-DHT podany noworodkom znamiennie obniżył zawartość 5-HT i 5-HIAA w badanych fragmentach mózgu dorosłych szczurów. U zwierząt z lezją ośrodkowego układu serotoninergicznego we wszystkich badanych częściach mózgu wykazano znamienny wzrost wychwytu (3H)glukozy. Badani antagoniści receptorów histaminowych nie wpływali na wychwyt (3H)glukozy w mózgu zwierząt grupy kontrolnej, natomiast chlorfeniramina zapobiegała wychwytowi glukozy tylko w korze mózgowej, a cymetydyna w korze mózgowej, hipokampie i móżdżku zwierząt z lezją ośrodkowego układu serotoninergicznego wywołaną podaniem noworodkom 5,7-DHT. WNIOSKI Wyniki wskazują na metaboliczne powiązania w mózgu ssaków między układem serotoninergicznym i histaminergicznym

Alternating Extremely Low Frequency Magnetic Field Increases Turnover of Dopamine and Serotonin in Rat Frontal Cortex

The aim of this study was to evaluate the influence of an extremely low frequency sinusoidal magnetic field (ELF MF) with frequency of 10 Hz and intensity of 1.8-3.8 mT on the levels of the biogenic amines dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 3-methoxytyramine (3-MT), 5-hydroxytryptamine (5-HT), 5-hydroxyindolacetic acid (5-HIAA), and noradrenaline (NA), as well as on DA and 5-HT turnover in corpus striatum and frontal cortex of adult male Wistar rats. We found that ELF MF exposure for 14 days, 1 h daily, did not influence the level of the examined biogenic amines and metabolites, but increased the rate of synthesis (turnover) of DA and 5-HT in rat frontal cortex as compared to control, sham exposed rats. On the basis of the present results and our previous findings, extremely low frequency magnetic field (ELF MF) exposure has been found to alter both turnover and receptor reactivity of monoaminergic systems, as well as some behaviors induced by these systems or their agonists and antagonists

Histaminergic Activity in a Rodent Model of Parkinson\u27s Disease

Rats lesioned shortly after birth with 6-OHDA have been proposed to be a near-ideal model of severe Parkinson\u27s disease, because of non-lethality of the procedure, near-total destruction of nigrostriatal dopaminergic fibers, and near-total dopamine (DA) denervation of striatum. There are scarce data that in Parkinson\u27s disease, activity of the central histaminergic system is increased. Therefore, the aim of this study was to determine histamine content in the brain and the effect of histamine receptor antagonists on behavior of adult rats. At 3 days after birth, Wistar rats were pretreated with desipramine (20.0 mg/kg ip) 1 h before bilateral icv administration of the catecholaminergic neurotoxin 6-OHDA (67 μg base, on each side) or saline-ascorbic acid (0.1%) vehicle (control). At 8 weeks levels of DA and its metabolites l-3,4- dihydroxyphenylalanine (DOPAC) and homovanillic acid (HVA) were estimated in the striatum and frontal cortex by HPCL/ED technique. In the hypothalamus, hippocampus, frontal cortex, and medulla oblongata, the level of histamine was analyzed by immunoenzymatic method. Behavioral observations (locomotion, exploratory-, oral-, and stereotyped-activity) were additionally made on control and 6-OHDA neonatally lesioned rats. Effects of DA receptor agonists (SKF 38393, apomorphine) and histamine receptor antagonists (e.g., S(+)chlorpheniramine, H 1 ; cimetidine, H 2 ; thioperamide, H 3 agonist) were determined. We confirmed that 6-OHDA significantly reduced contents of DA and its metabolites in the brain in adulthood. Histamine content was significantly increased in the hypothalamus, hipocampus, and medulla oblongata. Moreover, in 6-OHDA-lesioned rats behavioral response was altered mainly by thioperamide (H 3 antagonist). These findings indicate that histamine and the central histaminergic system are altered in the brain of rats lesioned to model Parkinson\u27s disease, and that histaminergic neurons exert a modulating role in Parkinsonian 6-OHDA-lesioned rats

Thioperamide, an H \u3csub\u3e3\u3c/sub\u3e Receptor Antagonist Prevents [ \u3csup\u3e3\u3c/sup\u3e H]Glucose Uptake in Brain of Adult Rats Lesioned as Neonates With 5,7-Dihydroxytryptamine

As a first attempt at exploring an association between histaminergic and serotoninergic neuronal phenotypes in glucose regulation, the influence of the histamine H 3 receptor antagonist thioperamide on glucose uptake by brain was determined in rats in which the serotoninergic innervations of brain was largely destroyed perinatally. Male Wistar rats were initially treated on the 3rd day after birth with the serotoninergic neurotoxin 5,7- dihydroxytryptamine (5,7-DHT) (75 μg icv) or saline vehicle (10 μl icv). At 8 weeks lesioned and control rats were terminated in order to validate the effectiveness of 5,7-DHT: reduction in 5-HT and 5-HIAA by 83-91% and 69-83% in striatum, frontal cortex, and hippocampus (HPLC/ED method). Other groups of rats were pretreated with thioperamide (5.0 mg/kg ip) or saline vehicle 60 min prior to 6-[ 3 H]-D-glucose (500 μCi/kg ip). Fifteen-min later rats were decapitated and brains were excised and dissected to remove frontal cortex, striatum, hippocampus, thalamus/hypothalamus, pons, and cerebellum. Liquid scintillation spectroscopy was used to determine that [ 3 H]glucose uptake, which was enhanced in 5,7-DHT lesioned rats in cortex (by 88%), hippocampus, thalamus/hypothalamus, pons and cerebellum (each by 47-56%), and in striatum (by 35%). In contrast, thioperamide prevented the enhancement in [ 3 H]glucose uptake in all brain regions of 5,7-DHT neonatally lesioned rats; and [ 3 H]glucose levels were significantly different in all brain regions (except thalamus/hypothalamus) in thioperamide-versus saline-treated rats. These findings indicate a functional association between histaminergic and serotoninergic systems in brain in relation to glucose regulation

Ontogenetic Serotoninergic Lesioning Alters Histaminergic Activity in Rats in Adulthood

The aim of this study was to determine histamine content in the brain and the effect of histamine receptor antagonists on behavior of adult rats lesioned as neonates with the serotonin (5-HT) neurotoxin 5,7-dihydroxytryptamine (5,7-DHT). At 3 days after birth Wistar rats were pretreated with desipramine (20 mg/kg ip) before bilateral icv administration of 5,7-DHT (37.5 μg base on each side) or saline-ascorbic (0.1%) vehicle (control). At 10 week levels of 5-HT and its metabolite 5-hydroxyindole acetic acid (5-HIAA) were determined in frontal cortex, striatum, and hippocampus by an HPLC/ED technique. In the hypothalamus, frontal cortex, hippocampus and medulla oblongata, the level of histamine was analyzed by an immunoenzymatic method. Behavioral observations (locomotion, exploratory-, oral-, and stereotyped activity) were performed, and effects of DA receptor agonists (SKF 38393, apomorphine) and histamine receptor antagonists S(+)chlorpheniramine (H1), cimetidine (H2), and thioperamide (H3) were determined. We confirmed that 5,7-DHT profoundly reduced contents of 5-HT and 5-HIAA in the brain in adulthood. Histamine content was also reduced in all examined brain regions. Moreover, in 5,7-DHT-lesioned rats the locomotor and oral activity responses to thioperamide were altered, and apomorphineinduced stereotype was intensified. From the above, we conclude that an intact central serotoninergic system modulates histamine H3 receptor antagonist effects on the dopaminergic neurons in rats