Effects of glucocorticoid on cyclic nucleotide-gated channels of olfactory receptor neurons.

OBJECTIVE: Cyclic adenosine monophosphate (cAMP) and cyclic nucleotide-gated (CNG) channels play an important role in olfactory perception. The purpose of this study was to explore the effect of glucocorticoid on the CNG channels of olfactory receptor neurons (ORNs). METHODS: For in vivo studies, rats were injected with dexamethasone 1 mg/kg body weight intraperitoneally once or once a day for 2 weeks. After 24 hours or 2 weeks, the difference in CNGA2 (the principal subunit of CNG channels) messenger ribonucleic acid (mRNA) in the ORNs was detected. For in vitro studies, the ORN membrane was extracted and incubated with 0.1 or 1 mg/mL dexamethasone for 5 or 30 minutes, respectively, and then the concentrations of cAMP were measured. For all experiments, normal saline was used as the control. RESULTS: For in vivo studies, compared with the normal saline group, CNGA2 mRNA could be upregulated in the 2-week group (p < .01) but not in the 24-hour group (p > .05). For in vitro studies, dexamethasone of both 0.1 and 1 mg/mL raised the concentration of cAMP in the ORNs at 5 and 30 minutes, respectively (p < .05), and the concentration of cAMP was higher in the 1 mg/mL groups than in the 0.1 mg/mL groups (p < .05). However, there was no significant difference between the 5-minute and 30-minute groups with either concentration. CONCLUSIONS: Glucocorticoid enhanced both the mRNA expression of CNG channels and the production of cAMP, which might be a possible pathway for treating olfactory disorders. The effect of glucocorticoid was dose-dependent.

[Clinical features of primary ciliary dyskinesia].

OBJECTIVE: To investigate the clinical features, diagnosis and treatment of primary ciliary dyskinesia (PCD). METHODS: Three cases of PCD received endoscopic sinus surgery and were followed up for life quality and recovery. Among these 3 cases, two were twin brothers and the other girl was twin born with a healthy brother. The mucosa of inferior turbinate was extracted prior to the operation without narcotic and decongestant. The ultrastructure of mucosal cilia was detected with electron microscope. Nine exons of gene DNAH5 and chromosome in one case and her fraternal twin were evaluated. RESULTS: Nasal and sinus CT imaging of the 3 cases showed chronic pansinusitis (1 case accompanied with situs inversus according with the diagnosis of Kartagener syndrome). The nasal polyp was resected, and the sinuses were opened. The twin brothers received the adenoidectomy. All patients felt nasal ventilation improved while the surgical field still covered with thick discharges during follow-up for 2 - 4 years. Ciliary ultrastructures of the three cases showed lateral dynein absent, the sequence of 9 exons of DNAH5 and chromosome presented no change in the fraternal twins. CONCLUSIONS: Surgery could improve the symptoms of sinusitis in PCD. Change of ciliary ultrastructure was an important indication of its pathological changes and molecular biology evaluation needs further study.

[Effect of Betamethasone on the cAMP of olfactory receptor neurons in rat].

OBJECTIVE: To observe the effects of Betamethasone on the cyclic adenosine monophosphate (cAMP) in olfactory receptor neurons (ORNs) and explore the possible mechanisms of the recovery of olfactory disorders by steroid treatment METHODS: ORNs membrane was extracted and incubated with 0.1 mg/ml and 1.0 mg/ml Betamethasone. The concentrations of cAMP were measured by enzyme-linked immunosorbent assay at different times. RESULTS: Compared with the control group, all Betamethasone groups showed differences, indicating 0.1 mg/ml (P < 0.05) and 1.0 mg/ml (P < 0.01) Betamethasone could rise the concentration of cAMP. The Betamethasone had obvious effects on cAMP production in rat ORNs and there was a dose-dependent effect. There was no difference between 5 minutes groups and 30 minutes groups. CONCLUSIONS: Steroid hormone could enhance the production of cAMP of ORNs. Steroid hormone may thus contribute to the recovery of olfactory disorders partially, at least, through the effect on AC-cAMP in olfactory transduction.

[Influence of breast carcinoma cells on normal endothelial cells: experimental study with a co-culture system].

OBJECTIVE: To study the influence of breast carcinoma cells on normal endothelial cells. METHODS: Human endothelial cells were isolated from umbilical cord blood. Medium Z-MCF-7-EC was established and was used to co-culture the normal endothelium cells (ECs) and human breast cancer cells of the line MCF-7. Normal endothelial cells cultured by itself were used as control. Light microscopy and transmission electron microscopy were used to observe the morphology of the 2 kinds of endothelial cells. Expression of the genes ESM, IGFBP-3, alphavbeta3, VE-C, and Tie-2-2 was analyzed by semi-quantitative RT-PCR using a house-keeping gene beta(2m) as inner reference gene. RESULTS: The ECs co-cultured with MCF-7 breast cancer cells were abnormal in shape with increased size of nucleus and nucleolus, increased size ratio of nuclear to nucleoplasm, increased depth of surface fenestration, loosed and distorted endoplasm, increased size of cell-cell junctions, decreased number of surface microvilli, and tubules formed by ECs. The expression values of the genes ESM, IGFBP-3, alphavbeta3, VE-C, and Tie-2-2 in the ECs co-cultured with MCF-7 breast cancer cells were all up-regulated in comparison with those in the controls (P < 0.01, P < 0.05, P < 0.01, P < 0.01, and P < 0.05 respectively). CONCLUSION: Breast cancer cells promote formation of new vessels with endothelial cells different from the normal ECs in character and behavior.