Expression and significance of TGF-β1, p38MAPK and BMP-7 protein in liver specimens of patients with alveolar hepatic echinococcosis / 中国血吸虫病防治杂志

Objective To detect the expression of transforming growth factor-β1 (TGF-β1), p38MAPK and bone morphogenetic protein-7 (BMP-7) protein in the liver specimens of patients with hepatic alveolar echinococcosis, and to investigate the potential role of TGF-β1, p38MAPK and BMP-7 protein in hepatic fibrosis caused by hepatic alveolar echinococcosis. Methods A total of 20 patients with hepatic alveolar echinococcosis were enrolled as study subjects, and hepatic specimens were sampled from the sites within 0.5 cm (Group A) and 0.5 to 1.5 cm from hepatic alveolar echinococcosis lesions (Group B), while normal liver specimens sampled from the sites 2 cm and greater from hepatic alveolar echinococcosis lesions served as controls (Group C). The fibrosis of liver specimens was pathological examined using HE and Masson staining, and the expression of TGF-β1, p38MAPK and BMP-7 protein was quantified in liver tissues using Western blotting. The associations of TGF-β1, p38MAPK and BMP-7 protein expression with hepatic fibrosis were assessed. Results HE staining showed the malaligned structure of hepatocytes and destruction of the structure of hepatic lobules at various degrees in liver specimens in groups A and B, with hepatocyte degeneration, atrophy and necrosis, hyperplasia of fibrous tissues and eosinophilic granulocyte infiltration seen, while no abnormal pathological alterations of liver tissues, normal hepatocyte structure and morphology and uniform size, no malaligned structure of hepatocytes, clear structure of hepatic lobules, no or mild hepatocyte degeneration or necrosis, and no eosinophilic granulocyte infiltration were seen in Group C. Masson staining showed that there was hyperplasia of multiple fibrous connective tissues in the liver portal areas in groups A and B, with fibrosis seen in hepatic lobules, while no obvious pathological changes were seen in Group C. There were significant differences seen in TGF-β1 (P < 0.001), p38MAPK (P < 0.01) and BMP-7 protein (P < 0.05) expression in liver tissues in groups A, B and C, and higher TGF-β1, p38MAPK and BMP-7 protein expression was quantified in groups A and B than in Group C (all P values < 0.05), while greater TGF-β1, p38MAPK and BMP-7 protein expression was detected in Group B than in Group C (all P values < 0.05). The expression of TGF-β1, p38MAPK and BMP-7 protein correlated positively with the severity of hepatic fibrosis (r = 0.866, 0.702 and 0.801, all P values < 0.05), and there were significant differences in TGF-β1 (F = 72.580, P < 0.01), p38MAPK (χ2 = 31.705, P < 0.01) and BMP-7 protein expression (χ2 = 48.388, P < 0.01) among liver tissues with different degrees of fibrosis. The TGF-β1 protein expression correlated positively with p38MAPK and BMP-7 protein expression (r = 0.607 and 0.702, both P values < 0.001), and the BMP-7 protein expression also correlated positively with p38MAPK protein expression (r = 0.456, P < 0.001). Conclusion The interaction among TGF-β1, p38MAPK and BMP-7 jointly participates in the development of hepatic fibrosis induced hepatic alveolar echinococcosis.

Nicotine regulates large conductance ca2+ activated K+ channels in rat coronary arterial smooth muscle cells / 中国应用生理学杂志

<p><b>OBJECTIVE</b>The present study was to explore signaling mechanisms underlying nicotine-induced inhibition of large-conductance calcium-activated potassium channels (BK(Ca)).</p><p><b>METHODS</b>8 week male Wistar rats were divided randomly into saline group and nicotine group and received respectively injection with saline or nicotine (Sigma, Shanghai, China) at 2 mg/(kg x d) for 21 days. Coronary vascular smooth muscle cells were dissociated enzymatically. Dissociated smooth muscle cells were interfered with CPT-cAMP (100 micromol/L) or forskolin (10 micromol/L). The signal channel open dwell-time (To), close dwell-time (Tc) and open probability (Po) were recorded.</p><p><b>RESULTS</b>CPT-cAMP or forskolin significantly prolonged To, shorten Tc and increased Po in saline group (P < 0.01). But in nicotine group To, Tc and Po did not been changed.</p><p><b>CONCLUSION</b>This phenomenon may serve as a physiological mechanism that nicotine inhibits BK(Ca) channel activity to increase via cAMP/PKA-dependent pathway.</p>

Changes of BKCa during aging and its correlation with blood pressure / 中国应用生理学杂志

<p><b>AIM</b>To investigate the changes of large-conductance calcium-activated potassium channels (BKCa, MaxiK) during aging and relations between the changes and blood pressure.</p><p><b>METHODS</b>Male spontaneously hypertensive rats (SHR) aged 9, 15, 21, 27, 33 weeks (the number of each weeks SHR was 4) were selected as hypertension group rats, corresponding gender, weeks and number Wistar-Kyoto rats (WKY) as control group rats. Blood pressure of abdominalis aorta of each weeks SHR and WKY were measured by BL-420F experimental system of biological function. The arteria mesenteric minor (AMM) were isolated in blunt dissection method. The vascular smooth muscle cells (VSMCs) of AMM were isolated with prolease. The potassium current, the current after BKCa were blockaded by Tetraethylammonium (TEA) and the capacitance of membrane (Cm) of VSMCs of AMM were recorded with using whole cell patch clamp, and calculated the BKCa current and the BKCa current density. Probe the correlation of the changes of BKCa current density with MABP during aging.</p><p><b>RESULTS</b>The potassium current density and BKCa current density of VSMCs of AMM of SHR were decreasing during aging, however, the changes of WKY had no statistically significance (P > 0.05). The BKCa current density was extremely correlative with MABP in SH R (the values of r were -0.7174), in WKY, the BKCa current density was correlative with MAB P r = -0.4832.</p><p><b>CONCLUSION</b>BKCa current and current density attenuate with aging, the level of blood pressure is response of the attenuated degree. The BKCa current density is extremely correlative with the blood pressure.</p>