Association between carotid plaque and Parkinson's disease.

BACKGROUND: Epidemiological studies show that patients with Parkinson's disease (PD) are prone to have a reduced incidence of ischemic cerebrovascular disease. Previous studies show the correlation between PD and the lipids serum levels. The PD,s patients are found with a reduced serum level of triglyceride and low-density lipoprotein cholesterol (LDL-C); thus, the level of serum uric acid (UA) is closely related to the occurrence and development of PD. Patients with low serum UA levels have a higher chance of developing PD than the ones who do not. However, the relationship between carotid plaques and PD is still unknown. METHODS: Our study was based on 68 patients with PD (known as the PD group) and 81 people without PD (known as the control group). Patients in the PD group were of the same age and gender. Both groups were recorded and analyzed for UA, LDL-C, and carotid plaques or intima-media thickness (IMT). The PD group was then divided into three subgroups: the stable plaque group, the unstable plaque group, and the non-plaque group. RESULTS: In the present study, the PD group showed a significantly lower level of UA and LDL-C than the control group (P<0.01); somehow there were no statistically significant differences in the IMT and plaque incidence between the two groups (P>0.05). There were also no significant differences (P>0.05) in both the LDL-C and UA levels in all subgroups, but there was a close relation in both age and duration of disease to IMT. According to the Hoehn and Yahr staging scale, serum levels of LDL-C were inversely correlated in PD patients, while UA was related to the duration of the disease. CONCLUSIONS: Our study suggested that there were no differences in carotid artery arteriosclerosis plaque and IMT, but the PD progress was indeed correlated with IMT. Meanwhile, LDL-C and UA had different priorities in H&Y and disease progression.

Flunarizine inhibits sensory neuron excitability by blocking voltage-gated Na+ and Ca2+ currents in trigeminal ganglion neurons.

BACKGROUND: Although flunarizine has been widely used for migraine prophylaxis with clear success, the mechanisms of its actions in migraine prophylaxis are not completely understood. The aim of this study was to investigate the effects of flunarizine on tetrodotoxin-resistant Na(+) channels and high-voltage activated Ca(2+) channels of acutely isolated mouse trigeminal ganglion neurons. METHODS: Sodium currents and calcium currents in trigeminal ganglion neurons were monitored using whole-cell patch-clamp recordings. Paired Student's t test was used as appropriate to evaluate the statistical significance of differences between two group means. RESULTS: Both tetrodotoxin-resistant sodium currents and high-voltage activated calcium currents were blocked by flunarizine in a concentration-dependent manner with the concentration producing half-maximal current block values of 2.89 µmol/L and 2.73 µmol/L, respectively. The steady-state inactivation curves of tetrodotoxin-resistant sodium currents and high-voltage activated calcium currents were shifted towards more hyperpolarizing potentials after exposure to flunarizine. Furthermore, the actions of flunarizine in blocking tetrodotoxin-resistant sodium currents and high-voltage activated calcium currents were use-dependent, with effects enhanced at higher rates of channel activation. CONCLUSION: Blockades of these currents might help explain the peripheral mechanism underlying the preventive effect of flunarizine on migraine attacks.

Flunarizine blocks voltage-gated Na(+) and Ca(2+) currents in cultured rat cortical neurons: A possible locus of action in the prevention of migraine.

Although flunarizine (FLN) has been widely used for migraine prophylaxis with clear success, the mechanisms of its actions in migraine prophylaxis are not completely understood. It has been hypothesized that migraine is a channelopathy, and abnormal activities of voltage-gated Na(+) and Ca(2+) channels might represent a potential mechanism of cortical hyperexcitability predisposing to migraine. The aim of the present study was to investigate the effects of FLN on Na(+) and Ca(2+) channels of cultured rat cortical neurons. Sodium currents (I(Na)) and calcium currents (I(Ca)) in cultured rat cortical neurons were monitored using whole-cell patch-clamp recordings. Both I(Na) and I(Ca) were blocked by FLN in a concentration-dependent manner with IC(50) values of 0.94µM and 1.77µM, respectively. The blockade of I(Na) was more powerful at more depolarizing holding potentials. The steady-state inactivation curve of I(Na) was shifted towards more hyperpolarizing potentials by FLN. FLN significantly delayed the recovery from fast inactivation of I(Na). Furthermore, the action of FLN in blocking I(Na) was enhanced at higher rates of channel activation. Blockades of these currents might help explain the mechanism underlying the preventive effect of FLN on migraine attacks.