Neuroscience letters
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Neuroscience letters · Feb 2000
Repeated administration of systemic gabapentin alleviates allodynia-like behaviors in spinally injured rats.
The effect of systemic gabapentin, a novel antiepileptic and analgesic, was tested on allodynia-like behaviors in spinal cord injured rats. On the first day of treatment 30 mg/kg intraperitoneal gabapentin did not alleviate hyper-reactivity to mechanical and cold stimulation. ⋯ Total alleviation of mechanical allodynia was observed in most rats after the third administration of gabapentin. Thus, build-up of the antiallodynic effect of gabapentin may develop through a time dependent mechanism or alternatively through a gradual accumulation of the effective central nervous system concentration of the drug.
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Fitts' law states that the movement time (MT) of an aiming movement is a linear function of the index of difficulty (ID), where ID = log2(2A/W, A is the movement amplitude, and W is the target width. This law implies that MT should remain unchanged as long as A/W remains constant (i.e. the absence of a scaling effect). The goal of this study was to investigate whether, during upright posture, reciprocal-pointing movements with the center of pressure location follow Fitts' law. ⋯ The results showed that for each A, MT was a linear function of ID. However, the slopes of the linear-regression lines increased with decreases in A. These findings indicate the presence of a scaling effect which violates Fitts' law.
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Neuroscience letters · Oct 1999
Comparative StudyNerve growth factor prevention of aged-rat sympathetic neuron injury by cisplatin, vincristine and taxol--in vitro explant study.
We examined the preventive effects of nerve growth factor (NGF) against neurotoxicity induced in aged rats by anticancer drugs such as cisplatin, vincristine and taxol using a superior cervical ganglion explant culture system. The inhibition of neurite outgrowth by cisplatin, vincristine and taxol was markedly prevented by co-treatment with NGF. The neurite and nerve cell populations were well preserved in vincristine and taxol, whereas cisplatin reduced these populations as compared with control even when treated with NGF. These results indicate that, just as in young adult rats, NGF prevents toxic sympathetic nerve injury induced by vincristine and taxol even in aged rats, but does not protect against cisplatin-induced nerve cell injury.
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Neuroscience letters · Sep 1999
The effect of riluzole and mannitol on cerebral oedema after cryogenic injury in the mouse.
A cryogenic lesion was produced under halothane anaesthesia in the mouse by placing a cotton swab soaked in liquid nitrogen onto the surface of the cranium. This provoked an oedematous lesion which developed within the hour after the insult and evolved over the following week. ⋯ Repeated doses (2 x 16 mg/kg, i.p.) of riluzole were also able to reduce oedema significantly (24%, P < 0.05) at 24 h post lesion. Riluzole, in four repeated doses of 8 mg/kg i.p. was also able to reduce lesion surface size by 16% (P < 0.05) 48 h after lesion.
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Neuroscience letters · Sep 1999
Comparative StudyDecrease in phantom limb pain associated with prosthesis-induced increased use of an amputation stump in humans.
The experience of phantom limb pain, non-painful phantom limb sensation and telescoping was ascertained by questionnaire in a group of upper extremity amputees wearing a functionally effective Sauerbruch prosthesis which permits extensive use of the affected limb and in a group of patients wearing a cosmetic prosthesis that did little to increase the utilization of the amputation stump. The Sauerbruch prosthesis group exhibited a significant and large decrease in amount of phantom limb pain while the cosmetic prosthesis group showed no change. Neither group experienced a decrease in non-painful phantom limb sensation or telescoping. ⋯ It is possible that the increased use of the amputation stump induced by wearing a Sauerbruch prosthesis produced a countervailing use-dependent, afferent-increase type of cortical reorganization that reversed the phantom limb pain. These preliminary results require replication. Their therapeutic implications are discussed.