Invasion and metastasis mechanism of human papillomavirus in head and neck squamous cell carcinomas / 华西口腔医学杂志

Human papillomavirus (HPV) is a major causative agent of head and neck squamous cell carcinomas (HNSCC). Over the past several decades, an increasing number of studies established the strong association of HPV with the invasion and metastasis of HNSCC. In the present study, we reviewed the gene mutations in HPV-associated HNSCC and the unique mechanism of E6- and E7-mediated carcinogenesis via interactions with an array of cellular elements. We further discussed the progress in the mechanisms of invasion and metastasis; these mechanisms include non-coding RNAs, deregulating cellular energetics, tumor microenvironment, cancer stem cells, angiogenesis, and lymphangiogenesis.

Facilitative effect of glycine on regulation of baroreflex in the hypothalamic paraventricular nucleus of conscious rats / 生理学报

The hypothalamic paraventricular nucleus (PVN) is a central site for integration of the endocrine system and the autonomic nervous system. Despite a number of studies have pointed out the importance of the PVN in the central regulation of cardiovascular functions, the chemical mediators in the PVN responsible for mediating baroreflex are not well understood. In the present study, we used the conscious rats to investigate the possible involvement of glycine (Gly) in PVN in the central regulation of baroreflex induced by intravenous injection of phenylephrine (0.8 mug/0.04 mL, in 3 min). Then, the microdialysis sampling was performed in the PVN and the concentration of Gly in the microdialysate was measured by high performance liquid chromatography (HPLC) combined with electrochemical techniques, and mean arterial pressure (MAP) and heart rate (HR) were recorded simultaneously. Injection of phenylephrine elicited a significant increase (P<0.01) in MAP from the baseline of (99.5+/-14.2) mmHg to the maximum of (149.8+/-19.5) mmHg and a decrease (P<0.01) in HR from the baseline of (400.8+/-33.1) beats/min to the minimum of (273.4+/-40.8) beats/min, respectively. Synchronously, the injection of phenylephrine increased the level of Gly in the microdialysate from the PVN to (162.9+/-27.3)% of the basal level (P<0.05). Perfusion of strychnine (100 mumol/L), an antagonist of Gly receptor, into the PVN enhanced the pressor response and attenuated the bradycardic response during the baroreflex, resulting in a decrease in baroreflex sensitivity (P<0.001). Whereas, the perfusion of Gly (1 mmol/L) into the PVN did not affect the pressor response but enhanced the bradycardic response during the baroreflex, resulting in an increase in baroreflex sensitivity (P<0.001). These results suggest that endogenous Gly in the PVN may act via strychnine-sensitive Gly receptor to produce a facilitative effect on baroreflex.

Cardiovascular change induced by central hypertonic saline are accompanied by GABA release in awake rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the possible involvement of gamma-aminobutyric acid (GABA) in the paraventricular nucleus (PVN) in cardiovascular responses induced by central salt loading.</p><p><b>METHODS</b>Direct perfusion into PVN region with hypertonic saline (0.6 mol/L) was performed in conscious rats by using an in vivo brain microdialysis technique. Then, the extracellular concentration of GABA in the PVN region was measured by microdialysis and high performance liquid chromatography (HPLC) techniques, and the blood pressure (BP) and heart rate (HR) were with recorded simultaneously. Bicuculline (an antagonist of GABAA receptor) or saclofen (an antagonist of GABAB receptor) were coperfused hypertonic saline into PVN region, then the cardiovascular responses were examined.</p><p><b>RESULTS</b>(1) The local perfusion of 0.6 mol/L saline elicited significant increases on BP and HR (P < 0.01). In addition, perfusion of 0.6 mol/L saline increased the extracellular GABA levels in the PVN region, which reached 561.96% +/- 173.96% (P < 0.05) of the basal level. (2) Bicuculline or salcofen significantly attenuated the in-response of BP (P < 0.01, respectively), whereas the antagonists did not influence the response of HR induced by hypertonic saline.</p><p><b>CONCLUSION</b>Local perfusion of hypertonic saline in the PVN region elicits a local release of GABA, which may act via GABA(A) and GABA(B) receptors to produce pressor response.</p>