| 31. |
- Lindberg, Olle R, et al.
(författare)
-
Epidermal growth factor treatment of the adult brain subventricular zone leads to focal microglia/macrophage accumulation and angiogenesis.
- 2014
-
Ingår i: Stem cell reports. - : Elsevier BV. - 2213-6711. ; 2:4, s. 440-8
-
Tidskriftsartikel (refereegranskat)abstract
- One of the major components of the subventricular zone (SVZ) neurogenic niche is the specialized vasculature. The SVZ vasculature is thought to be important in regulating progenitor cell proliferation and migration. Epidermal growth factor (EGF) is a mitogen with a wide range of effects. When stem and progenitor cells in the rat SVZ are treated with EGF, using intracerebroventricular infusion, dysplastic polyps are formed. Upon extended infusion, blood vessels are recruited into the polyps. In the current study we demonstrate how polyps develop through distinct stages leading up to angiogenesis. As polyps progress, microglia/macrophages accumulate in the polyp core concurrent with increasing cell death. Both microglia/macrophage accumulation and cell death peak during angiogenesis and subsequently decline following polyp vascularization. This model of inducible angiogenesis in the SVZ neurogenic niche suggests involvement of microglia/macrophages in acquired angiogenesis and can be used in detail to study angiogenesis in the adult brain.
|
|
| 32. |
- Zhang, Jianhua, 1961, et al.
(författare)
-
Repeated administration of amphetamine induces sensitisation to its disruptive effect on prepulse inhibition in the rat.
- 1998
-
Ingår i: Psychopharmacology. - 0033-3158. ; 135:4, s. 401-6
-
Tidskriftsartikel (refereegranskat)abstract
- Male Sprague-Dawley rats were repeatedly treated with amphetamine (AMP, 1 mg/kg, SC) at 3- day intervals for 15 days and tested for prepulse inhibition of acoustic startle after each treatment. This treatment regimen induced sensitisation in the animals as evidenced by a progressive increase in the disruptive effect of AMP on prepulse inhibition. Persistent changes in brain function was indicated, since an increase in disruptive effect was observed in sensitised animals also after a 22-day-long drug- and test-free period. The development of sensitisation was blocked by pretreatment with haloperidol (HPD, 0.1 mg/kg, SC), which suggests that sensitisation to the disruptive effect of AMP was dependent on dopamine (DA) D2 receptor activation. Furthermore, the development of sensitisation was blocked by adrenalectomy, which suggests that sensitisation was dependent also on circulating adrenal hormones. Increased DA-ergic activity has been implicated in the pathophysiology of schizophrenia and AMP-induced sensitisation to the neuronal functions that modulate prepulse inhibition may be an experimental model to investigate this hypothesis.
|
|
| 33. |
- Birnir, Bryndis, et al.
(författare)
-
The impact of sub-cellular location and intracellular neuronal proteins on properties of GABA(A) receptors
- 2007
-
Ingår i: Current Pharmaceutical Design. - : Bentham Science Publishers Ltd.. - 1381-6128 .- 1873-4286. ; 13:31, s. 3169-3177
-
Tidskriftsartikel (refereegranskat)abstract
- Most studies of GABA(A) receptor accessory proteins have focused on trafficking, clustering and phosphorylation state of the channel-forming subunits and as a result a number of proteins and mechanisms have been identified that can influence the GABA(A) channel expression and function in the cell plasma membrane. In the light of a growing list of intracellular and transmembrane neuronal proteins shown to affect the fate, function and pharmacology of the GABA(A) receptors in neurons, the concept of what constitutes the native GABA(A) receptor complex may need to be re-examined. It is perhaps more appropriate to consider the associated proteins or some of them to be parts of the receptor channel complex in the capacity of ancillary proteins. Here we highlight some of the effects the intracellular environment has on the GABA-activated channel function and pharmacology. The studies demonstrate the need for co-expression of accessory proteins with the GABA(A) channel-forming subunits in heterologous expression systems in order to obtain the full repertoire of GABA(A) receptors characteristics recorded in the native neuronal environment. Further studies e.g. on gene-modified animal models are needed for most of the accessory proteins to establish their significance in normal physiology and in pathophysiology of neurological and psychiatric diseases. The challenge remains to elucidate the effects that the accessory proteins and processes (e.g. phosphorylation) plus the sub-cellular location have on the "fine-tuning" of the functional and pharmacological properties of the GABA(A) receptor channels.
|
|
| 34. |
- Eghbali, M, et al.
(författare)
-
Hippocampal GABA(A) channel conductance increased by diazepam
- 1997
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 388:6637, s. 71-75
-
Tidskriftsartikel (refereegranskat)abstract
- Benzodiazepines, which are widely used clinically for relief of anxiety and for sedation, are thought to enhance synaptic inhibition in the central nervous system by increasing the open probability of chloride channels activated by the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). Here we show that the benzodiazepine diazepam can also increase the conductance of GABAA channels activated by low concentrations of GABA (0.5 or 5 microM) in rat cultured hippocampal neurons. Before exposure to diazepam, chloride channels activated by GABA had conductances of 8 to 53pS. Diazepam caused a concentration-dependent and reversible increase in the conductance of these channels towards a maximum conductance of 70-80 pS and the effect was as great as 7-fold in channels of lowest initial conductance. Increasing the conductance of GABAA channels tonically activated by low ambient concentrations of GABA in the extracellular environment may be an important way in which these drugs depress excitation in the central nervous system. That any drug has such a large effect on single channel conductance has not been reported previously and has implications for models of channel structure and conductance.
|
|
| 35. |
- Lindquist, Catarina, et al.
(författare)
-
Extrasynaptic GABA(A) channels activated by THIP are modulated by diazepam in CA1 pyramidal neurons in the rat brain hippocampal slice
- 2003
-
Ingår i: Molecular and Cellular Neuroscience. - 1044-7431 .- 1095-9327. ; 24:1, s. 250-257
-
Tidskriftsartikel (refereegranskat)abstract
- Single-channel currents were activated by THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol) in cell-attached patches on CA1 pyramidal neurons in the rat hippocampal slice preparation. THIP activated GABA(A) channels after a delay that was concentration-dependent and decreased by 1 muM diazepam. The currents showed outward rectification. Channels activated at depolarized 40 mV relative to the chloride reversal potential had low conductance (<40 pS) but the conductance increased with time, resulting in high-conductance channels (>40 pS). The average maximal-channel conductances for 2 and 100 muM THIP were 59 and 62 pS (-Vp = 40 mV), respectively, whereas in 2 muM THIP plus 1 muM diazepam, it was 71 pS. The results show that in hippocampal neurons THIP activates channels with characteristics similar to those of channels activated by low concentrations (0.5-5 AM) of GABA. The increase in the inhibitory conductance with membrane depolarization permits gradation of the shunt pathway relative to the level of the excitatory input. (C) 2003 Elsevier Science (USA). All rights reserved.
|
|
| 36. |
- Rask-Andersen, Mathias, et al.
(författare)
-
Advances in kinase targeting : current clinical use and clinical trials
- 2014
-
Ingår i: TIPS - Trends in Pharmacological Sciences. - : Elsevier BV. - 0165-6147 .- 1873-3735. ; 35:11, s. 60-76
-
Forskningsöversikt (refereegranskat)abstract
- Phosphotransferases, also known as kinases, are the most intensively studied protein drug target category in current pharmacological research, as evidenced by the vast number of kinase-targeting agents enrolled in active clinical trials. This development has emerged following the great success of small-molecule, orally available protein kinase inhibitors for the treatment of cancer, starting with the introduction of imatinib (Gleevec (R)) in 2003. The pharmacological utility of kinase-targeting has expanded to include treatment of inflammatory diseases, and rapid development is ongoing for kinase-targeted therapies in a broad array of indications in ophthalmology, analgesia, central nervous system (CNS) disorders, and the complications of diabetes, osteoporosis, and otology. In this review we highlight specifically the kinase drug targets and kinase-targeting agents being explored in current clinical trials. This analysis is based on a recent estimate of all established and clinical trial drug mechanisms of action, utilizing private and public databases to create an extensive dataset detailing aspects of more than 3000 approved and experimental drugs.
|
|
| 37. |
|
|
| 38. |
- Wallén-Mackenzie, Åsa, et al.
(författare)
-
Restricted cortical and amygdaloid removal of vesicular glutamate transporter 2 in preadolescent mice impacts dopaminergic activity and neuronal circuitry of higher brain function.
- 2009
-
Ingår i: The Journal of neuroscience : the official journal of the Society for Neuroscience. - 1529-2401 .- 0270-6474. ; 29:7, s. 2238-51
-
Tidskriftsartikel (refereegranskat)abstract
- A major challenge in neuroscience is to resolve the connection between gene functionality, neuronal circuits, and behavior. Most, if not all, neuronal circuits of the adult brain contain a glutamatergic component, the nature of which has been difficult to assess because of the vast cellular abundance of glutamate. In this study, we wanted to determine the role of a restricted subpopulation of glutamatergic neurons within the forebrain, the Vglut2-expressing neurons, in neuronal circuitry of higher brain function. Vglut2 expression was selectively deleted in the cortex, hippocampus, and amygdala of preadolescent mice, which resulted in increased locomotor activity, altered social dominance and risk assessment, decreased sensorimotor gating, and impaired long-term spatial memory. Presynaptic VGLUT2-positive terminals were lost in the cortex, striatum, nucleus accumbens, and hippocampus, and a downstream effect on dopamine binding site availability in the striatum was evident. A connection between the induced late-onset, chronic reduction of glutamatergic neurotransmission and dopamine signaling within the circuitry was further substantiated by a partial attenuation of the deficits in sensorimotor gating by the dopamine-stabilizing antipsychotic drug aripiprazole and an increased sensitivity to amphetamine. Somewhat surprisingly, given the restricted expression of Vglut2 in regions responsible for higher brain function, our analyses show that VGLUT2-mediated neurotransmission is required for certain aspects of cognitive, emotional, and social behavior. The present study provides support for the existence of a neurocircuitry that connects changes in VGLUT2-mediated neurotransmission to alterations in the dopaminergic system with schizophrenia-like behavioral deficits as a major outcome.
|
|
| 39. |
- Bergman, Penny, et al.
(författare)
-
Age-related decline in senses and cognition: A Review
- 2021
-
Ingår i: Senses and Sciences. - : IVL Svenska Miljöinstitutet. - 2284-2489. ; 8:2, s. 1264-1292
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Age-related decline in the senses is well-known, with a decline in the sensitivity of all senses having been observed. Decline in the senses can be connected to different neurological disorders and cognitive function and may even be a possible predictor of death. Aim: The aim of this narrative review was to find and explore recent literature on the covariation between age-related decline in the different senses and co-existing effects on cognitive ability and quality of life. Results and Discussion: Six themes could be identified, these were: “Decline due to normal ageing?”, “Technical aids and solutions”, “Wellbeing”, “Memory training”, “Verbal exercises” and “Sensory training”. Large differences between the different senses were obtained. However, the senses showed similar patterns in the different themes. Conclusion: It could be concluded that there are many similarities concerning the connections between the decline in individual senses and cognition and memory. Measurements of wellbeing and quality of life are common in the evaluation of the senses, and all types of decline have an impact on activities in daily life.
|
|
| 40. |
- Birnir, Bryndis, et al.
(författare)
-
Bicuculline, pentobarbital and diazepam modulate spontaneous GABA(A) channels in rat hippocampal neurons
- 2000
-
Ingår i: British Journal of Pharmacology. - : Wiley. - 1476-5381 .- 0007-1188. ; 131:4, s. 695-704
-
Tidskriftsartikel (refereegranskat)abstract
- Spontaneously opening, chloride-selective channels that showed outward rectification were recorded in ripped-off patches from rat cultured hippocampal neurons and in cell-attached patches from rat hippocampal CA1 pyramidal neurons in slices. In both preparations, channels had multiple conductance states and the most common single-channel conductance varied. In the outside-out patches it ranged from 12 to 70 pS (Vp=40 mV) whereas in the cell-attached patches it ranged from 56 to 85 pS (-Vp=80 mV). Application of GABA to a patch showing spontaneous channel activity evoked a rapid, synchronous activation of channels. During prolonged exposure to either 5 or 100 microM GABA, the open probability of channels decreased. Application of GABA appeared to have no immediate effect on single-channel conductance. Exposure of the patches to 100 microM bicuculline caused a gradual decrease on the single-channel conductance of the spontaneous channels. The time for complete inhibition to take place was slower in the outside-out than in the cell-attached patches. Application of 100 microM pentobarbital or 1 microM diazepam caused 2 - 4 fold increase in the maximum channel conductance of low conductance (<40 pS) spontaneously active channels. The observation of spontaneously opening GABA(A) channels in cell-attached patches on neurons in slices suggests that they may have a role in neurons in vivo and could be an important site of action for some drugs such as benzodiazepines, barbiturates and general anaesthetics.
|
|
