Biomedical subjects

G Z Wei

Publications and source records attributed to G Z Wei.

15 recordsLinked to original sources

PubMed1998

[Apamin sensitive component of Ca(2+)-activated K+ current of afterhyperpolarization, IAHP, in dorsal root ganglion neurons in rat].

Whole-cell voltage clamp technique was used to record the tail current in freshly isolated dorsal root ganglion (DRG) neurons of rat with an aim to investigate whether these neurons possess an apamin sensitive component of Ca(2+)-activated K+ current, IAHP. The results are as follows: (1) the amplitudes of the tail currents increased from 9.3 +/- 2.8 pA to 64.1 +/- 3.4 pA (P < 0.001) when the depolarizing duration was increased from 1 ms to 180 ms; (2) the amplitudes of the tail current were reduced when repolarizing pulses were applied, with a reversal potential of about -63 mV; (3) the amplitude of the tail current was significantly depressed or even almost completely blocked by extracellularly applied 500 mumol/L Cd2+ or intracellularly applied 11 mmol/L EGTA; (4) the amplitudes of the tail currents were decreased by about (26.32 +/- 3.9)% (P < 0.01) after 200 nmmol/L apamin was extracellularly applied; and (5) the fast component of the tail current was sensitive to 10 mmol/L TEA while the slow component was insensitive. These results suggest that an apamin sensitive component of Ca(2+)-activated K+ current may be present in afterhyperpolarization of DRG neurons.

Animals↗

PubMed1994

[Increased plasma endothelin-1 concentration in acute cerebral infarction and its clinical significance].

In acute cerebral ischemia there are severe damages of endothelium recognized as the stimuli for secretion of endothelin-1, that is a endothelium-derived peptide and seems to be the most potent vasoconstrictor known. The goal of this study is to measure plasma endothelin-1 level in patients with cerebral infarction and determine the relationship between endothelin-1 and ischemic stroke. Plasma level of endothelin-1 was measured in 21 consecutive patients. The measurement was performed 3 times at different stages of stroke. There was a marked increase in plasma endothelin-1 level in the patients and the elevation lasted the entire acute and subacute stage of stroke. There was a correlation between the peptide concentration and infarct volume (r = 0.665, P < 0.01). The result suggests that endothelin-1 plays an important role in the regulation of brain circulation. Apparent and lasting increase in plasma level of endothelin-1 is associated with cerebral ischemia and infarction. The peptide seems to be involved in the pathophysiology of acute cerebral ischemia and have a deleterious effect in the evolution of cerebral infarction.

Acute Disease↗

PubMed1994

[Vascular parkinsonism: verified clinicopathological correlation in a case].

Classifications of Parkinsonism in the past have induced an "arteriosclerotic" variety and vascular etiology has thus been proposed. However, controversy exists whether such an entity actually exists, because there has not been a single pathologically verified case with adequate clinical correlation. We report a case with clinical syndrome indistinguishable from Parkinson disease and postmortem examination revealing extensive lacunar infarction of the basal ganglia without evidence of coexistent Parkinson disease. This case provides pathologic confirmation for the concept of vascular Parkinsonism.

Aged↗

PubMed1993

Increased plasma endothelin-1 concentration in patients with acute cerebral infarction and actions of endothelin-1 on pial arterioles of rat.

In acute cerebral ischemia there are severe damages of endothelium which have been recognized as the stimuli to secrete endothelin-1, an endothelium-derived peptide and the most potent vasoconstrictor ever known. This study was to measure plasma endothelin-1 level in patients with cerebral infarction and explore the relationship between endothelin-1 and ischemic stroke. The possible involvement of endothelin-1 in local regulation of cerebral arterioles was also investigated. Plasma levels of endothelin-1 were measured by radioimmunoassay in 21 patients. Using a micro-video system, the endothelin-1 actions were also observed on rat pial arterioles in vivo, and with incomplete cerebral ischemia model (rat), effect of ischemia affects the endothelin-1 action. There was a marked increase in plasma endothelin-1 level in the patients and the elevation persisted during the acute and subacute period of stroke. There was a positive correlation between the peptide concentration and infarct size (r = 0.655, P < 0.01). In rats, endothelin-1 (dose range: 10(-10) mole/L-10(-7) mole/L) induced a dose-dependent arteriole contraction after subdural administration. Arteriole calibers were decreased by 27.7% +/- 3.8% (10(-9) mole/L), 46.8% +/- 4.9% (10(-8) mole/L) and 78.5% +/- 4.7% (10(-7) mole/L), respectively. Cerebral ischemia significantly enhanced the action of endothelin-1 (96.4% +/- 7.2% vs 58.2% +/- 6.8%). Endothelin-1 plays an important role in regulating local circulation of ischemic brain. The notable and lasting increase in plasma level of endothelin-1 are associated with cerebral ischemia and infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1991

[Crow-Fukase syndrome. A report of 2 cases].

Two cases of crow-fukase syndrome were reported. Both cases showed the characteristic polyneuropathy, organomegaly, endocrinologic disturbances and skin involvement. There was no evident response to cortico--steroid therapy.

Adult↗

PubMed1988