Search results for "TYR"

Ethopharmacological studies on the effects of antihormones on rodent agonistic behavior with especial emphasis on progesterone.

1991

The effects of a range of antiandrogens and antiestrogens on conflict behaviors in laboratory rats and mice are reassessed in the light of recent studies applying ethophamacological analyses (recording the full spectrum of behaviors) to such investigations. It is argued that any antihostility properties of the antiandrogen cyproterone acetate are largely a consequence of indirect actions on odor communication, whereas antiestrogens (e.g., tamoxifen and CI 680) seem to have more fundamental motivational effects in addition to communicatory actions. A detailed example of the approach is provided in which progesterone (which can be antiandrogenic) is given to rats paired in different ways. The…

Evidence for the existence of FGFR1-5-HT1A heteroreceptor complexes in the midbrain raphe 5-HT system.

2015

The ascending midbrain 5-HT neurons known to contain 5-HT1A autoreceptors may be dysregulated in depression due to a reduced trophic support. With in situ proximity ligation assay (PLA) and supported by co-location of the FGFR1 and 5-HT1A immunoreactivities in midbrain raphe 5-HT cells, evidence for the existence of FGFR1–5-HT1A heteroreceptor complexes were obtained in the dorsal and median raphe nuclei of the Sprague–Dawley rat. Their existence in the rat medullary raphe RN33B cell cultures was also established. After combined FGF-2 and 8-OH-DPAT treatment, a marked and significant increase in PLA positive clusters was found in the RN33B cells. Similar results were reached upon coactivati…

The effects of methacholine and calcium deprivation on the release of the false transmitter, ?-methyladrenaline, from the isolated rabbit heart

1976

1. Anaesthetized rabbits were infused for 20 min with 85 μg · kg−1 · min−1 (±)-α-methyladrenaline. The hearts dissected 15 min after the infusion contained 1.49 μg/g α-methyladrenaline; the endogenous noradrenaline content was correspondingly decreased. 2. Hearts from α-methyladrenaline-infused animals were isolated with the right sympathetic nerves intact and perfused. Ventricular rate, right atrial and right ventricular tensions were recorded using the transverse method. 3. Electrical stimulation (10 Hz, 1 ms, 1 min) of sympathetic nerves, perfusion with the nicotinic drug, p-aminophenethyltrimethylammonium (PAPETA) or perfusion with 54 mM KCl (high K+) solution evoked an output of both α…

Evidence for noradrenaline and adrenaline as sympathetic transmitters in the chicken.

1975

1 The concentrations of noradrenaline and adrenaline in various organs, arterial plasma and venous outflow from isolated hearts of adult chickens have been determined. 2 The relative adrenaline concentrations (percentage of the sum of noradrenaline and adrenaline) in the heart (33%), spleen (16%) and brain (26%) were higher than those found in mammalian organs. Chemical sympathectomy by pretreatment with 6-hydroxydopamine caused a decrease of the noradrenaline and adrenaline concentrations in the heart to 20 and 23% and in the spleen to 16 and 29%, respectively. 3 Stimulation of the right sympathetic nerves, infusion of tyramine or infusion of a modified Tyrode solution containing 108mM K+ …

Transient oligemia is associated with long-term changes in binding densities of cortical inhibitory GABAA receptors in the rat brain

2009

Recently, we could demonstrate in rats that a short transient oligemic period of only 20-minute duration, induced by systemic hypotension, resulted in a transient decline of spatial memory capacities without any histological damage over a subsequent period of 6 months. In our present study, we checked for more subtle alterations within the highly vulnerable hippocampal CA1 subfield using quantification of neuronal cell density and semi-quantitative analysis of the ischemia-sensitive protein MAP2. Since hippocampal excitatory and inhibitory neurotransmitter receptors are crucially involved in spatial memory processes, quantitative in vitro receptor autoradiography was performed using [(3)H]M…

Differential inhibition of biphenyl hydroxylation in perfused rat liver

1978

A differential inhibition of biphenyl hydroxylation by alpha-naphthoflavone and metyrapone was observed in isolated perfused rat liver. alpha-Naphthoflavone inhibited 2- and 4-hydroxylation in livers from beta-naphthoflavone-pretreated animals but had no effect on both reactions in livers from phenobarbital-pretreated animals. Metyrapone inhibited 2- and 4-hydroxylation in phenobarbital-stimulated livers, but only insignificant inhibition of 2-hydroxylation and a slight enhancement of 4-hydroxylation by metyrapone was observed in beta-naphthoflavone-stimulated livers. Conjugation of 2-hydroxybiphenyl and 4-hydroxybiphenyl by isolated perfused livers was also studied. 4-Hydroxybiphenyl prefe…

The Potential of Antiestrogens as Centrally-Acting Antihostility Agents: Recent Animal Data

1988

Recent studies suggest that motivations for certain forms of masculine behavior including social aggression are mediated by central estrogen receptors. Two studies using antiestrogens in rodent species were performed. Intact male LH rats were given Tamoxifen or vehicle for 4 or 8 days. The three possible pairings were videotaped for 60 min. Intact male OF1 mice were given CI-680 or vehicle over 25 days. Similar pairings were carried out but some CI-680 or vehicle animals were paired with anosmic opponents. Encounters were videotaped for 10 min. In both experiments evidence was obtained that the antiestrogen markedly reduced time allocated to offense. Any variations in defense were a consequ…

Sacubitril/valsartan and short-term changes in the 6-minute walk test: A pilot study

2018

Background: Impaired exercise capacity is the most disabling symptom in patients with heart failure with reduced ejection fraction (HFrEF). Despite sacubitril/valsartan showing reduced long-term morbidity and mortality over enalapril in HFrEF, its effects on short-term functional capacity remain uncertain. We sought to evaluate the effects of sacubilril/valsartan on a 30-day six-minute walk test in eligible patients with HFrEF. Methods and results: From November 1, 2016 to February 1, 2017, a total of 58 stable symptomatic patients with HFrEF were eligible for sacubitril/valsartan and underwent 6-MWT before and 30 days after initiation of sacubitril/valsartan therapy. A mixed-effects model …

Early Sacubitril/Valsartan-driven Benefit on Exercise Capacity in Heart Failure With Reduced Ejection Fraction: A Pilot Study

2017

6-Hydroxydopamine lesioning differentially affects α-synuclein mRNA expression in the nucleus accumbens, striatum and substantia nigra of adult rats

2002

The effect of a unilateral 6-hydroxydopamine (6-OHDA) lesion and/or repeated administration of levodopa (L-DOPA) to normal and 6-OHDA-lesioned rats on alpha-synuclein mRNA expression was investigated by in situ hybridization histochemistry. A 6-OHDA lesion of the nigro-striatal pathway alone, confirmed by the loss of nigral tyrosine hydroxylase mRNA expression, markedly decreased alpha-synuclein mRNA in the lesioned substantia nigra (SN). In contrast, the levels of alpha-synuclein mRNA in the denervated striatum and nucleus accumbens were not altered. Chronic administration of L-DOPA to normal or 6-OHDA-lesioned rats had no effect on alpha-synuclein mRNA expression in the SN, striatum or nu…