Linked Life Data

7898675

Source:http://linkedlifedata.com/resource/pubmed/id/7898675

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1995-4-26
pubmed:abstractText
We employed intracellular electrophysiological techniques to examine the effects of a prolonged anoxia (more than 7 min superfusion with artificial cerebrospinal fluid saturated with 95% N2-5% O2) on dopaminergic neurons of the rat ventral mesencephalon maintained in vitro. A prolonged anoxia caused an inhibition of the spontaneous firing and a sustained (mean 16 min) and slowing declining hyperpolarization of the membrane in 30 dopaminergic cells. This was associated with a decrease of the apparent input resistance at 5, 10, 15 and 20 min of O2 deprivation by 38% (n = 18), 42% (n = 8), 48% (n = 18) and 54% (n = 8) of control, respectively. The continuation of anoxia, 1-4 min after the hyperpolarizing period, induced an irreversible depolarization (n = 8). More than 50% of the cells (17 of 30) fully recovered their electrophysiological properties after 15 min of O2 deprivation. Since the intracellular diffusion of cesium (a potassium channel blocker) was able to block the hyperpolarization and to reveal a depolarization caused by anoxia, we tested whether the blockade of the hyperpolarization modified the resistance of the cells to O2 deprivation. We observed that the cells loaded with cesium were depolarized and damaged in a period of O2 deprivation less than 10 min. The apparent input resistance of these neurons was irreversibly reduced by 36% of the control at 5 min of anoxia (n = 6). Furthermore, in order to ascertain whether an impairment of the sodium/potassium pump due to energy failure is involved in the anoxia-induced depolarization, we blocked the Na+/K+ ATPase pump with the inhibitor ouabain.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0306-4522
pubmed:author
pubmed:issnType
Print
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
757-64
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Responses of rat mesencephalic dopaminergic neurons to a prolonged period of oxygen deprivation.
pubmed:affiliation
Clinica Neurologica, Università di Roma, Italy.
pubmed:publicationType
Journal Article, In Vitro