Wang Di-xun

Inhibition of expression of hypoxia-inducible factor-1α mRNA by nitric oxide in hypoxic pulmonary hypertension rats

SummaryIn order to study the effect of nitric oxide (NO) on the expression of hypoxia-inducible factor-1 alpha (HIF-1α) mRNA in hypoxic pulmonary hypertension (HPH) rats, 30 healthy male Wistar rats were randomly divided into normoxic control group, chronic hypoxic group and hypoxia plus L-argine (L-Arg) group. The animal model of HPH was developed. The mean pulmonary arterial pressure (mPAP) was measured by inserting a microcatheter into the pulmonary artery. The HIF-1α mRNA expression levels were detected by in situ hybridization (ISH) and semiquantitative RT-PCR. It was found that after 14 days hypoxia, the mPAP in normoxic control group (17.6±2.7 mmHg,l mmHg=0.133 kPa) was significantly lower than that in chronic hypoxic group (35.8 ±6.1 mmHg,t=0.2918,P<0.05) and mPAP in chronic hypoxic group was higher than that in hypoxia plus L-argine group (24.4±3.8 mmHg,t=0.2563,P<0.05). ISH showed that the expression of HIF-1α mRNA in the intraacinar pulmonary arteriolae (IAPA) in normoxic control group (0.1076±0.0205) was markedly weaker than that in chronic hypoxic group (0.3317±0.0683,t=3.125,P<0.05) and that in chronic hypoxic group was stronger than that in hypoxia plus L-argine group (0.1928±0.0381,t=2.844,P<0.05). RT-PCR showed that the content of HIF-1α mRNA in chronic hypoxic group (2.5395±0.6449) was 2.16 times and 1.75 times higher than that in normoxic control group (1.1781±0.3628) and hypoxia plus L-argine group (1.4511±0.3981), respectively. It is concluded that NO can reduce the mPAP by the inhibition of the expression of HIF-1α mRNA, which may be one of the mechanisms through which NO affects the pathogenesis of HPH.

Effects of 3,4-dihydroxyacetophenone on cytosolic calcium in pulmonary artery endothelial and smooth muscle cells during acute hypoxia.

SummaryThe effects of 3, 4-Dihydroxyacetophenone (3, 4-DHAP) on cytosolic free calcium [Ca2+]i in pulmonary artery endothelia (PAECs) and smooth muscle cells (PASMCs) during acute hypoxia were studied. Porcine pulmonary artery endothelial and smooth muscle cells (PASMCs) were cultured primarily, and they were divided into 4 groups: groups incubated under normoxia or hypoxia and those with or without treatment with 3, 4-DHAP. The [Ca2+]i of both PAECs and PASMCs was measured by determining the fluorescence of fura 2 AM on spetrofluorometer. Our results showed that hypoxia caused significant elevation of [Ca2+]i, in both PAECs and PASMCs, 3, 4-DHAP could attenuate the hypoxic elevation of [Ca2+]i, only in PASMCs but not in PAECs. It is concluded that 3, 4-DHAP decreases the hypoxic elevation of [Ca2+]i in PASMCs. This might contribute to its inhibitory effect on hypoxic pulmonary vasoconstriction.

Effects of L-tetrahydropalmatine on NOS III gene expression in hypoxia and cultured porcine cerebral arterial endothelial cells during reoxygenation

SummaryTo investigate the expression of NOS III mRNA and protein in cultured porcine cerebral arterial endothelial cells (CAEC) during hypoxia and reoxygenation and the effects of L-Tetrahydropalmatine (L-THP) on the gene expression of NOS III in CAEC during hypoxia and reoxygenation. The cultured CAEC were divided into 5 groups; control, hypoxia, hypoxia+reoxygenation, hypoxia +L-THP and reoxygenation +L-THP groups. NOS III mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR). Immunocytochemistry was used to detect the level of NOS III protein. The expression of NOS III mRNA and protein were increased when CAEC were exposed to hypoxia for 1 h, and significantly decreased during reoxygenation 2, 6 and 12 h after 1-h of hypoxia. L-THP from 10−8 mol/L to 10−3 mol/L could inhibit the up-regulation of NOS III gene expression during hypoxia and down-regulation of NOS III gene expression during reoxygenation.

Die Anwendung der Impedanz-Pulmonal-Rheographie zur Abschätzung des Pulmonalarteriendruckes — eine unblutige Methode

ZusammenfassungBei 105 Patienten wurde während der Rechtsherzkatheteruntersuchung gleichzeitig das Impedanz-Pulmonal-Rheogramm (IPR) registriert. Die Korrelation zwischen dem Mitteldruck der Arteria pulmonalis {fx193-01} und der Höhe der dZ-Welle (H) im IPR und dem Verhältnis von Präejektionsperiode (Q-B) zu Austreibungsphase (B-P2) des rechten Ventrikels wurde analysiert. Dadurch bekommen wir die Multiregressionsformel: {fx193-02} Es ist möglich, mit der IPR, einer unblutigen Methode, den Pulmonalarteriendruck bei Cor pulmonale abzuschätzen, und die Entwicklung der pulmonalen Hypertonie zu beobachten.

Ätiologische Untersuchung der Brenngefühlkrankheit

ZusammenfassungDie Brenngefühlkrankheit ist eine in den vergangenen Jahren aufgetretene Erkrankung in Baumwollanbaugebieten. Die Patienten leiden an Störungen der Thermoregulation und an Sterilität.Durch ätiologische Untersuchungen, klinische Beobachtungen, Tierexperimente und Vorbeugungspraxis wurde festgestellt, daß diese Krankheit ihrer Natur nach eine chronische Vergiftung ist und das Gift in rohem Baumwollsamenöl vorhanden ist. Das Gossypol, ein toxischer Bestandteil der Baumwollsamen, ist die Ursache der Erkrankung.