Comparison of the retinal modulation transfer function between amblyopes successfully corrected and normal subjects.

AIM: To analyze the retinal modulation transfer function between amblyopes whose visual acuity was corrected to 5.0 and normal subjects at the same age. METHODS: RM-800 used to detect contrast sensitivity was adopted to measure MTF of 96 amblyopes (96 eyes) whose visual acuity was corrected to 5.0 and 80 normal controls (80 eyes) at the same age under six interference fringes (IVA=0.06, 0.1, 0.2, 0.4, 0.6, 0.8). RESULTS: The functional values of amblyopes were significantly lower than those of normal subjects in every fringe (P<0.01), especially in medium and high frequency. CONCLUSION: For amblyopes, MTF was still abnormal after stopping the treatments.

Dynamic monitoring of total plasma homocysteine in spontaneously hypertensive rats by LC-MS.

Hypertension has been recognized to be closely related to plasma homocysteine levels (tHcy). Spontaneously hypertensive rats (SHR) are used widely for hypertension research, but it is unclear whether hypertension is related to high levels of tHcy in rat plasma. To test whether hyperhomocysteinemia occurs in SHR we dynamically measured plasma total homocysteine (tHcy) in SHR by liquid chromatography-tandem mass spectrometry (LC-MS). This analytical method has good linearity within the range of 1-100 micromol/L for tHcy in rat plasma with a correlation coefficient of R = 0.9975. After dynamic monitoring (12 weeks) on the plasma tHcy in SHR and Wistar-Kyoto rats, we found that there was no significant difference in tHcy level between SHR and Wistar-Kyoto rats, which was 6.98 +/- 1.82 micromol/L and 8.04 +/- 1.64 micromol/L, respectively. And there was no significantly high level of plasma tHcy in SHR.

[Substance P and its receptors are involved in the effect of histamine H3 receptor agonist, IMETIT on nasal allergic symptoms in guinea pigs].

OBJECTIVE: To explore the influence of histamine H3 receptor agonist, IMETIT and simultaneous use of IMETIT and H1-receptor antagonist, Loratadine, on the symptoms of allergic rhinitis (AR) and substance P(SP) secretion and expression of SP receptor (SP-R) mRNA in AR model in guinea pigs. METHODS: Guinea pigs were divided randomly into 4 groups: AR group (group A), IMETIT group (group B), Loratadine group (group C) and IMETIT+Loratadine group (group D). The severity of AR was assessed by determining the extent of three markers of allergic symptoms (sneezing, nasal rubbing and nose blocking). The changes in the nasal mucosa were studied by pathological methods. The expression of positive cell of SP was detected by immunohistochemistry. SP-R mRNA expression in nasal mucosa was used to do reverse transcriptive-polymerase chain reaction (RT-PCR). Statistical analysis was performed using a SPSS 13.0 software. RESULTS: In Group B, the mean (x ± s) number of sneeze [(15.0 ± 1.3) times], scratching nose [(16.5 ± 2.3) times] and respiratory frequency [(76.3 ± 4.1) times/min] were significantly improved than those in group A [(23.5 ± 2.6) times, (26.1 ± 4.1) times and (66.5 ± 5.8) times/min, respectively), P value were 0.000, 0.000 and 0.001, respectively]. The numbers of SP-positive cells [(11.6 ± 3.6)/HP] and SP-R mRNA expression (0.64 ± 0.04) in group B were reduced significantly compared to group A [(27.1 ± 9.7)/HP, (0.83 ± 0.03), P value were 0.000, 0.000, respectively]. Sneeze [(10.0 ± 2.3) times], scratching nose [(11.8 ± 1.7) times] and respiration [(90.0 ± 5.0) times/min] in Group D were improved significantly than those in group B (P value were 0.000, 0.002 and 0.000, respectively). SP-positive cells [(2.0 ± 1.7)/HP] and SP-R mRNA expression (0.52 ± 0.06) in Group D compared with group B were also significantly reduced (P value were 0.012 and 0.000, respectively). Pathological changes in guinea pig nasal mucosa in group B, group D were alleviated than those in group A. The combination of IMETIT and Loratadine had a synergistic effect on these effects (F value were 11.59, 8.28, 5.61, 5.48, 6.50, respectively, P value were 0.002, 0.008, 0.025, 0.027, 0.017). CONCLUSIONS: IMETIT and the combination of IMETIT with Loratadine can effectively relieve the symptoms of AR in guinea pigs, its mechanism may be relevant to reduce SP secretion and the expression of SP-R mRNA, and the two has a synergistic effect. It may be useful as a novel therapeutic approach in nasal allergy.