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- Ekström, Anders, 1965-, et al.
(author)
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Pengarna eller humaniora?
- 1997
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In: Dagens Nyheter. - Stockholm. ; :21/10
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Journal article (pop. science, debate, etc.)
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3. |
- Edbladh, Magnus, et al.
(author)
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Early regeneration in vitro of adult mouse sciatic axons is dependent on local protein synthesis but may not involve neurotrophins
- 1994
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In: Neuroscience Letters. - : Elsevier BV. - 0304-3940. ; 168:1-2, s. 37-40
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Journal article (peer-reviewed)abstract
- The sensory axons of the adult mouse sciatic nerve were shown to regenerate after a local test crush lesion in vitro in a serum-free medium. The average outgrowth distance of the leading axons after culturing for 3 days was 2.8 ± 0.1 mm, which was shorter than in vivo (3.8 ± 0.2 mm). With the use of a compartmentalised culture system we could show that regeneration was partially dependent on local protein synthesis in the injury region. The initial stages of regeneration did not seem to involve neurotrophins since both K252a and K252b, selective and nontoxic inhibitors of the neurotrophin actions, failed to inhibit axonal growth. The present in vitro model system offers favourable conditions to investigate the early events of the regeneration process in an adult mammalian peripheral nerve.
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4. |
- Edström, Anders, et al.
(author)
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Adenosine inhibition of the regeneration in vitro of adult frog sciatic sensory axons
- 1992
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In: Brain Research. - 0006-8993. ; 570:1-2, s. 35-41
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Journal article (peer-reviewed)abstract
- The sensory axons of the adult frog sciatic nerve have earlier been shown to regenerate in vitro. If a local test crush is made at the initiation of culturing, regeneration starts after 3.4 days and proceeds at a rate of about 0.8-0.9 mm/day for several days. In the present experiments regeneration was inhibited by adenosine in a reversible and dose-dependent fashion. Similarly, both an adenosine analogue, 2-chloroadenosine (2-CA), and a non-hydrolyzable ATP analogue, AMP-PNP, reduced the outgrowth of sensory axons. The effect of adenosine was partially antagonized by theophylline at a critical concentration. Using a compartmental system, it could clearly be shown that adenosine exerted its effects at the outgrowth region. Adenosine, 2-CA, and AMP-PNP were also found to inhibit the proliferation of Schwann cells in the regenerating nerve. Various experiments showed that the latter can not explain the outgrowth inhibitory effects, which could be mediated by adenosine receptors associated with the elongating axons.
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5. |
- EDSTRÖM, Anders, et al.
(author)
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Is protease activity involved in fast axonal transport?
- 1984
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In: Acta Physiologica Scandinavica. - : Wiley. - 0001-6772 .- 1365-201X. ; 121:4, s. 379-384
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Journal article (peer-reviewed)abstract
- N‐a‐p‐Tosyl‐L‐Lysine Chloromethyl Ketone (TLCK), a protease inhibitor, was found to irreversibly inhibit rapid axonal transport of protein in vitro in the frog sciatic nerve. TLCK exerted its action at the axonal level and seemed to depress the rate rather than the amount of transported protein. The efficiency of TLCK as a protease inhibitor was demonstrated by polyacrylamide gel electrophoresis, which showed that degradation of high molecular weight proteins (presumably neurofilament subunits) into a 25 000 dalton protein could be induced by exposing the frog nerves to triton‐X and prevented by the presence of TLCK. Findings that TLCK, at a transport inhibiting concentration (0.1 mM), had little or no effects on either protein synthesis or ATP levels, suggest that TLCK did not affect transport due to general cytotoxic properties. The effects of TLCK is discussed in relation to possible roles of protease activity in axonal transport.
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6. |
- Edström, Anders, et al.
(author)
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Moderate elevation of extracellular potassium transiently inhibits regeneration of sensory axons in cultured adult sciatic nerves
- 1995
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In: Brain Research. - 0006-8993. ; 693:1-2, s. 148-154
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Journal article (peer-reviewed)abstract
- The adult frog dorsal root ganglia (DRG) together with the sciatic nerve (ScN) has previously been shown to survive in organ culture for several days. If a local test crush is made at the beginning of culturing, there is an initial delay of about 3 days before the sensory axons start to grow into the distal nerve stump at a rate of about 0.6-0.9 mm/day. The present results showed that axonal growth was unaffected in preparations maintained for 8 days in medium containing 10 mM K+ (5 mM is the physiological level). In contrast, the outgrowth was markedly reduced by 15 mM K+ and still more by 20 and 25 mM K+. The growth inhibition was partially counteracted by nifedipine, a Ca2+-channel antagonist. Other experiments clearly showed that high K+ exerted its effects during the early phase of the regeneration and lacked effects at later stages. The possibility that Ca2+-binding proteins, e.g., calbindin, which showed immunohistochemical reactivity in different structures, contribute to the growth adaptation to high K+ will be considered. The generality of the findings was supported by inhibition of axonal outgrowth of adult mouse sciatic sensory axons by high K+.
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7. |
- Edström, Anders, et al.
(author)
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Regeneration in vitro of the adult frog sciatic sensory axons
- 1990
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In: Restorative Neurology and Neuroscience. - 0922-6028. ; 1:3-4, s. 261-266
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Journal article (peer-reviewed)abstract
- The adult frog sciatic nerve offers several advantages as an in vitro model to study nerve regeneration. The nerve with the attached dorsal root ganglia can easily be isolated and incubated in a culture medium for several days. If the nerve is subjected to a crush immediately after dissection there is a delay of 3.4 days after which the sensory axons start to regenerate into the distal nerve stump at a constant rate of about 1.1 mm · day−1 in serum-containing and 1.0 mm · day−1 in serum-free medium. Serum-free cultures may be used in future studies to examine the effect of various neurotrophic factors. The existence of an accurate method for examining the outgrowth distance, based on axonal transport of labelled proteins, contributes to the attractiveness of the model. A compartmental culture system permits separate exposure of the ganglia and the nerve to different agents. Taking advantage of this, pharmacological studies suggest that Schwann cells produce signals, dependent on newly transcribed RNA, which transform the preparation into a growth state. The present model system offers favourable conditions to learn more about the early events and also the subsequent steps of the regeneration process.
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8. |
- Edström, Anders, et al.
(author)
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The use of the regenerating frog sciatic nerve for pharmacological studies of orthograde and retrograde axonal transport
- 1987
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In: Brain Research. - : Elsevier BV. - 0006-8993. ; 401:1, s. 34-42
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Journal article (peer-reviewed)abstract
- The outgrowth region of the regenerating frog sciatic nerve shows an increased permeability for various drugs, which has been utilized for pharmacological studies of axonal transport. Six days after a bilateral crush lesion, the nerves, including the spinal ganglia, were incubated in a compartmented chamber. Orthograde transport was assessed from the proximodistal distribution and the accumulation of labelled proteins in the nerve growth region. Retrograde transport was examined by allowing orthogradely transported materials to reverse at the regenerating region and then to accumulate at a ligature during a second incubation period. The distribution of radioactivity along the nerve was assayed by fluorography of whole-mount nerve preparations or by scintillation counting. Fluorography made it possible to increase the spatial resolution and to demonstrate effects in the elongating part of the regenerating nerve. Colchicine at low concentrations (10-100 μM) only inhibited axonal transport in the outgrowth region (6 mm long at 6 days after crush) and along some mm of the nerve proximal to the crush. Compound 48/80 (50 μg/ml), the most specific calmodulin inhibitor so far described, inhibited the transport along the same part of the nerve. Cytochalasin B (10 μg/ml) inhibited transport by effects limited to the outgrowth region. Both orthograde and retrograde transport showed sensitivity to these and some other drugs. The regenerating frog sciatic nerve seems to have significant advantages for pharmacological studies of axonal transport.
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10. |
- Ekström, Anders, 1965-
(author)
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Att leva i världens mitt
- 1995
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In: Upsala Nya Tidning. - Uppsala. ; :29/5
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Journal article (pop. science, debate, etc.)
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