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Ispitivan je utjecaj histamina, te blokatora histaminskih H1 receptora (antazolin, prometazin) i H2 receptora (cimetidin, ranitidin) na izometrijsku kontrakciju spiralnih isječaka humane umbilikalne vene.

Alzheimer's disease (AD) is characterized by progresive loss of memory The cholinergic cells of the nucleus basalis of Meynert (NBM) have recently been found to degenerate in AD and are thought to be at least partly responsible for the cognitive deficits which are main characteristics of this disease. Intact cholinergic system is a prerequisite to unimpaired performance in learning and memory tasks. Because lesions of NBM reduce memory, it was of interest to study the effect of various cholinergics or nootropic drug-piracetam on the passive avoidance acquisition in the rat with bilateral electrolytic lesions of NBM equivalent. Drugs used were: lecithin (3, 2x10-4 mol/kg i.p.), arecoline (6, 4x10-6 mol/kg i.p.), piracetam (1, 4x10-2 mol/kg i.p.), piracetam (1, 4x10-2 mol/kg i.p.) + arecoline (6, 4x10-6 mol/kg i.p.) and piracetam (1, 4x10-2 mol/kg i.p.) + lecithin (3, 2x10-4 mol/kg i.p.). NBM lesions significantly impaired the passive avoidance acquisition related to the control group. The avoidance acquisition deficit was improved by arecoline or lecithin or by lecithin with piracetam or by arecoline with piracetam while piracetam alone didn't influence it significantly.

The influence of the application of histamine on the smooth muscle tonus of human umbilical vein was investigated.

The influence of cholinomimetic drugs arecoline, physostigmine and lecithin on the passive avoidance acquisition in nucleus basalis lesioned rats was investigated.

Ispitivan je utjecaj noradrenalina na regulaciju tjelesne temperature štakora. Noradrenalin (20µg) i dibenzilin (10µg) ubrizgavani su narkotiziranoj životinji (Tiopenton-natrium 50 mg/kg i.p.) u nucleus preopticus medialis hypothalami u volumenu od 1 µl. Rektalna temperatura eksperimentalnih životinja mjerena je svakih 15 minuta od momenta injiciranja noradrenalina tijekom narednih 60 minuta. Rezultati naših ispitivanja pokazuju da noradrenalin injiciran u prednji hipotalamus snizuje rektalnu temperaturu štakora, dok dibenzilin antagonizira njegovo hipotermičko djelovanje.

Approximately 70% cholinergic projections of the frontoparietal neocortex is derived from ACh neurons in substantia innominata/nucl1eus basalis (SI/NB). The purpose of this study was to examine: 1) the influence of SI/NB lesion on the passive avoidance acquisition in the rat, and 2) if arecoline (1 mg/kg i.p.), physostigmine (0, 1 mg/kg i.p.) and lecithine (250 mg i.p.) may reverse the memory deficit of lesioned rats. Bilateral SI/NB lesion significantly impaired the passive avoidance acquisition related to the control group and sham lesioned rats. Acquisition was significantly improved in arecoline-treated rats, while physostigmine or lecithine didn't influence it significantly.

The influence of histamine on isometric contraction of helically cut strips of human umbilical vein was examined. In low concentrations histamine caused slightly expressed relaxation, while in higher concentrations (over 3.10-7 g.ml- 1) histamine caused marked contraction of isolated organ. H1 blockers (phenergan and antistine) antagonized both histamine effects, while H2 blocker (cimetidin) intensified contractile response of histamine. We suppose that histamine caused mentioned effects by influence on H1 receptors in umbilical vein smooth muscle.

Ispitivano je kontraktilno djelovanje histamina na izoliranom spiralnom isječku humane umbilikalne vene. Nađeno je da histamin uzrokuje o dozi ovisnu kontrakciju stijenke vene. Kontraktilna aktivnost histamina može se suzbiti pomoću blokatora histaminskih H1 receptora, dok se blokadom histaminskih H2 receptora ne utječe značajno na djelovanje histamina.

Ispitivan je utjecaj obostrane elektrolitičke lezije nakupine magnocelularnih neurona, smještenih ventromedijalno od globusa palidusa, na pasivno ispitivanje kazne u štakora. Pronađeno je uništenje spomenute strukture značajno smanjuje mogućnost životinja da izbjegnu kaznu, pa iz toga zaključujemo da je očuvanost ispitivanih neurona bitna za ostvarivanje procesa učenja i pamćenja u štakora.

A major cholinergic projection to the neocortex originates from the cell bodies in the nucleus basalis of Maynert (NBM). Because the cholinergic system has a specific relationship to cognitive functions and lesions of NBM reduce memory, it was of interest to study the effect of piracetam (2 g/kg i.p.), dihydroergotoxine (DHE- 0.1 mg/kg i.p.) and arecoline (1.0 mg/kg i.p.) on the passive avoidance acquisition in the rat with NBM lesion. Bilateral NBM electrolytic lesion significantly impaired the passive avoidance acquisition related to the control group and sham lesioned rats. The avoidance acquisition deficit was improved by arecoline while piracetam or DHE didn't influence it statistically.

Ispitivan je utjecaj noradrenalina, te α -adrenergijskih blokatora-dibenamina i dibenzilina, injiciranih u preoptičku medijalnu jezgru hipotalamusa, na rektalnu temperaturu anesteziranih štakora. Utvrđeno je da: 1.noradrenalin (20 mcg) uzrokuje signifikantan pad rektalne temperature, 2.blokatori α -adrenergijskih receptora - dibenamin i dibenzilin, ne mijenjaju temperaturu statistički značajno, ali 3.u cijelosti antagoniziraju hipotermijski učinak noradrenalina

Ispitivano je djelovanje kofeina i teofilina na frekvenciju rada izoliranog desnog atrija zamorčadi. Nađeno je da kofein a mnogostruko jače teofiilin uzrokuju pozitivno kronotropno djelovanje. Reserpin i alfa-metil DOPA smanjuju pozitivno kronotropnu aktivnost ispitivanih metilksantina. Propranolol uzrokuje bradikardiju, koju naknadno dani metilksantini još više pojačavaju., The chronotropic activity of caffeine and theophylline on the isolated right atrium of the guinea pig was examinated. Theophylline caused a significant and caffeine only a slight increase in the atrial rate. Reserpine and alpha methyl DOPA diminished the chronotropic activity of the Investigated methyl xanthines. Propranolol caused a decrease in the atrial rate. Caffeine and theophylline potentiated the negative chronotropic activity of propranolol.