“Rats lesioned shortly after birth with 6-OHDA have been proposed to be a near-ideal model of severe Parkinson’s 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’s 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 check details of the catecholaminergic neurotoxin 6-OHDA (67 mu g 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 GDC-0068 mouse 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, AZD9291 research buy 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’s disease, and
that histaminergic neurons exert a modulating role in Parkinsonian 6-OHDA-lesioned rats.”
“Fourier transform infrared (FTIR) analyses of low-k materials exposed to either oxygen radicals or to capacitively coupled O(2) plasma indicate that carbon depletion from these materials is dominated by O radical diffusion. FTIR measurements of changes in absorbance related to silanol formation (3500 cm(-1)) and carbon depletion (2980 cm(-1), 900-700 cm(-1)) exhibit a linear dependence on the square root of the exposure time. Diffusion is faster for a sample of higher porosity and interconnectedness (k=2.54) than for a sample with lower porosity (k=3.0). However, a sample with high porosity (k=2.57) but low interconnectedness (as measured by liquid diffusion) exhibits a high initial rate of carbon loss, followed by no further carbon loss at longer times. Further, pretreatment of k=3.