The work was carried out to investigate the effects of clonidine on Ach quantal release of presynaptic nerve terminals in guinea pig celiac ganglia in vitro by means of intracellular recording technique. After perfusion of celiac ganglia with clonidine ( 10?mol/L ) for 7 ~10 min, the frequency of spontaneous miniature excitatory postsynaptic potentials ( mEPSP ) which was increased by high K+ (15 mmol/L ) , diminished about 35% with little change in amplitude. Under condition of low Ca2+( 0.5mmol/L )/high Mg2+( 5.5mmol/L ) presynaptic nerve was repetitively stimulated by 200 pulses ( 1 Hz), the failure number of EPSP increased from 82 to 145 in 200 stimuli and the quantal content ( m ) decreased about 62% with little change in quantal size ( q ) under clonidine ( 10?mol/L ) action. It is indicated that clonidine can decrease Ach auantal release from presynaptic nerve terminals without effecting Ach content in vesicles, and is one of the mechanisms for depressant effect of clonidine on synaptic transmission of the sympathetic ganglia.

BACKGROUND: A middle cerebral artery occlusion and reperfusion(MCAO/R) model in rats with suture has been widely used in the researches of acute focal ischemic cerebral infarction, while the model in rabbits by the same method is relatively rare. Magnetic resonance diffusion weighted imaging (MR DWI) has been paid close attention recently for its sharp sensitivity of cerebral ischemia.OBJECTIVE: To establish rabbit models of MCAO/R by intraluminal thread, and study the characteristics of MR DWI after cerebral ischemia and reperfusion.DESIGN: Random controlled animal experiment.SETTING: Institute of Cerebrovascular Diseases, Affiliated Hospital of Qingdao University Medical College.MATERIALS: The experiment was accomplished at the Key Laboratory of Brain Diseases Prevention and Cure of Shandong Province from March to June in 2005. A total of 103 adult healthy New Zealand rabbits of either sex, 10-12 weeks old and 1.8-3.3 kg weight were provided by the Experimental Animal Center of Shandong Agricultural Academy (SCX20040013).They were bred at quiet, sanitary and dry conditions.METHODS: Animal groups: 103 rabbits were divided randomly into group A (n=53) and group B (n=50). The rabbits in group A were treated with suture of 0.51-0.55 mm as the diameter of thread, while group B was reassigned into B1 (0.46-0.50 mm), B2 (0.51-0.55 mm) and B3 (0.56-0.60 mm).The successful MCAO/R models in 57 cases were randomly divided into permanent ischemia group (n=30, ischemia 1, 3, 6, 12, 24 andl 48 hours, 5ones at each time point) and ischemic reperfusion group (n=27, reperfusion 0, 2 and 5 hours, 5 ones at each time point; reperfusion 11, 23 and 47hours, 4 ones at each time point). Another 10 rabbits receiving sham operations were regarded as contrasts for permanent ischemia group and ischemia reperfusion group, with 5 ones in each.MAIN OUTCOME MEASURES: The changes of hyperintensity area on DWI and apparent diffusion coefficient (ADC) were measured in permanent ischemia group and ischemic reperfusion group.RESULTS: The data of 57 successful model rabbits were involved in the result analysis.①The successful rate in group A (26 cases, 49.1%) was significantly lower than that in group B (31 cases, 62.0%).②In ischemia group:The hyperintensity area on DWI with declined ADC appeared at ischemia 1 hour. The hyperintensity areas on DWI at different times increased gradually from ischemia 1 hour and unchanged within 24 hours. The mean ADC at different times declined at first and then gradually increased.③In reperfusion group: Comparing with ischemia 1 hour, the hyperintensity area on DWI reduced while ADC increased at reperfusion 2 hours and 5 hours, and enlarged with ADC high at reperfusion 11 hours, then continued to enlarge with ADC reduced significantly at 23 hours and 47 hours.CONCLUSION: The diameter of thread tip and the inserting distance of thread are main factors for establishing successful MCAO/R models. The hyperintensity area on DWI and the decreasing ADC after acute cerebral ischemia can be improved by early reperfusion, but the secondary decreasing ADC may be induced by continuously reperfusion.

BACKGROUND: The clinical features and classification of various anomalous synkinetic movements related to ocular muscles caused by abnormal innervations have not been fully understood.OBJECTIVE: To report and analyze the clinical features of anomalous synkinetic movements related to ocular muscles caused by abnormal innervations, as well as to classify them according to the same neuromuscular nerves.DESIGN: A retrospective case analysis.SETTING: Department of Ophthalmology, the Affiliated Hospital of the Medical College of Qingdao University.PARTICIPANTS: The study was mainly conducted in the Department of Ophthalmology, the Affiliated Hospital of the Medical College of Qingdao University. A total of 836 cases of abnormal ocular movements were found from January 1997 to January 2002. Among them 67 cases of anomalous synkinetic movements were diagnosed.METHODS: All patients were inquired of case history and their ocular movements were examined. The anomalous synkinetic movements were found and classified into congenital and acquired. All cases were analyzed according to the same neuromuscular nerves, such as between branches of oculomotor nerve, oculomotor and abducens nerve, supranucleus and other anomalous synkinetic movements.lous synkinetic movements were determined by inquiring the history of observed.RESULTS: Sixty-seven anomalous synkinetic movements (8%) of 836 abnormal ocular movements were diagnosed; congenital anomalous synkinetic movements were the most common ones (88.06%) and were often seen in patients with Duane's syndrome. Anomalous synkinetic muscles occurred the most common between lateral and medial rectus, lateral rectus and levator palpebrae muscle (36.89% respectively) in congenital cases, and those occurred between inferior rectus and levator palpebrae muscle more commonly (30%) in acquired cases.CONCLUSION: Anomalous synkinetic movements related to ocular muscles are not infrequently seen. When we find paradoxical movements between ocular muscles, or between ocular muscles and other unrelated muscles, anomalous synkinetic movements should be considered.

Objective To observe the application of amniotic membrane in conjunctival sac plasty.Methods 24 cases with different eye diseases were performed with conjunctival sac plasty,in which 11 eyes were performed with amniotic membrane transplantation,5 eyes with symblepharon which adhered with cornea or emerged neovascularization were performed with amniotic membrane transplantation and lamellar keratoplasty,other 8 eyes were performed with amniotic membrane transplantation and conjunctival fornixe.They were followed up for 6~12 months.Results There was no inflammation observed after operation.The transplanted amniotic membrane turned transparent and the conjunctiva at sewing location crawled to amnion 10 d after operation.One month later,the neonatal conjunctiva covered transplanting region completely.Among the 24 eyes,9 eyes were healed,13 eyes were improved,and 2 were ineffective.Conclusion Amniotic membrane is a kind of effective material during conjunctival sac plasty for narrow conjunctival sac.