Search results for "Azepines"
showing 5 items of 135 documents
Glutathione-dependent resistance of the European eel Anguilla anguilla to the herbicide molinate
2001
Eels of species Anguilla anguilla were exposed to 5/4 LC50 (41.8 mg/l) of the herbicide molinate for 96 h in a time to death (TTD) test. Glutathione content (GSx, GSH, GSSG), glutathione reductase (GR) and gamma-glutamyl transpeptidase (gamma-GT) activities were determined in the liver and muscle tissues of dead and surviving (intoxicated) animals and compared to control values (non-exposed eels). TTD was positively correlated to hepatic GSH, GSH:GSSG ratio, hepatic and muscular GR, but negatively correlated to muscular GSH, which was severely depleted. Furthermore, glutathione and enzyme activities were intercorrelated, especially GSH and GR. These results indicate that eels which were abl…
Relaxant effect of dopamine on the isolated rat uterus.
1988
The effect of dopamine was studied on the isolated uterus of diethylstilboestrol-treated rats. Dopamine, at concentrations (10(7)-10(-4) M) produced a concentration-dependent relaxation in the K+-depolarized rat uterus. On a molar basis, dopamine was about 500 times less potent than adrenaline in relaxing the uterus, the maximum degree of relaxation obtained with both drugs was the same. Pretreatment of the rats with reserpine (5 mg/kg) did not produce any modification of the dose-response curve to dopamine. Similarly, cocaine (3 x 10(-6) M) failed to modify the relaxant effect of dopamine. The dopamine induced relaxation was inhibited by propranolol (10(-9)-10(-7) M) in a dose-dependent ma…
Impact of serotonin 2C receptor null mutation on physiology and behavior associated with nigrostriatal dopamine pathway function.
2009
The impact of serotonergic neurotransmission on brain dopaminergic pathways has substantial relevance to many neuropsychiatric disorders. A particularly prominent role has been ascribed to the inhibitory effects of serotonin 2C receptor (5-HT2CR) activation on physiology and behavior mediated by the mesolimbic dopaminergic pathway, particularly in the terminal region of the nucleus accumbens. The influence of this receptor subtype on functions mediated by the nigrostriatal dopaminergic pathway is less clear. Here we report that a null mutation eliminating expression of 5-HT2CRs produces marked alterations in the activity and functional output of this pathway. 5-HT2CR mutant mice displayed i…
D2-dopamine receptor blockade modulates temporal resolution in goldfish.
2002
A possible effect of dopamine on the temporal resolution of goldfish was investigated in a behavioral, two-alternative, forced-choice procedure. Flicker fusion frequency (FFF) was measured before and after bilateral intravitreal injections of D1- or D2-dopamine receptor (D1-/D2-R) antagonists, or after depletion of retinal dopamine by bilateral intravitreal injections of the dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA). Prior to drug injections, fish achieved FFFs of 33–39 Hz. A D1-R antagonist, SCH 23390, reduced FFF by about 12% (P > 0.1), whereas a D2 antagonist, sulpiride, reduced the relative FFF by 25% (P < 0.03). Depletion of retinal dopamine with 6-OHDA induced a gradual…
Dopamine agonists in schizophrenia: a review.
1995
Although it is unlikely that the different types of course and severity of schizophrenia are caused by one neurochemical abnormality alone, indirect pharmacological evidence still suggests a relative excess of dopaminergic activity being implicated in the pathogenesis of most of the schizophrenic symptoms, e.g. positive symptomatology. Synthesis and release of dopamine as well as firing rates of dopaminergic neurons are controlled by stimulation of autoreceptors via a negative feedback regulation. Investigations on therapeutic effects of autoreceptor-nonselective dopamine agonists in schizophrenia have yielded inconsistent results. Dopamine autoreceptor agonists like pramipexole, roxindole,…