Objective:To observe the cross-links between stereocilia on guinea pig utricle hair cells. Method:Twenty-four utricles from pigmented guinea pigs were examined using high resolution scanning (SEM)andtransmission electron microscopy(TEM). Result:an extensive network of cross-links occurs between stereociliaof utricle hair cells. These links fall into three categories. Upward-pointing links:from the tips of shorterstereocilia to the side of the adjacent taller stereocilia;Side-to-side links:between stereocilia of the same row;Row-to-row links :between adjacent rows. Conclusion :The existence of the stereociliary cross-links binds the hairbundles together and may be associated with the transduction process.

AIM To study the effects of quateranary ammonium salt derivative (F 2) of haloperidol on ischemia and reperfusion injury in rat hearts. METHODS Ischemia and reperfusion injury in rat hearts was induced by occluding the left anterior descending coronary artery for 30 min and restoring blood reperfusion for 30 min. F 2 (1, 2, 4 mg?kg -1 , respectively) was intravenously injected before heart ischemia. Plasma creatine kinase (CK), creatine kinase isoenzyme MB(CK MB), lactate dehydrogenase(LDH),? Hydroxybutyrate dehydrogenase (HBDH), grutamic oxalacetic transaminase(GOT), superoxide dismutase (SOD) activity and malondiadehyde (MDA) contents were measured. The pathologic changes of ischemia and reperfusion myocardium were observed on the transmission electron microscopy. RESULTS F 2 reduced the release of CK,CK MB LDH,HBDH,GOT from I/R rat hearts, increased the activity of SOD and decreased the MDA contents. In F 2 (1mg?kg -1 ) group, the serum CK MB LDH HBDH concentration was lowered significantly (vs I/R group P

AIM: To investigate the changes in nNOS and iNOS expression of hippocampal CA3 pyramidal neurons and NO - 2/NO - 3 level of hippocampal homogenate of rats induced by stress, and to explore the effect of phenytoin on them. METHODS: Rats were subjected to forced-swimming stress, phenytoin was administered(ip) at 30 min before stress. Using the immunohistochemistry and the computerized image technique, the expression levels of nNOS and iNOS of rat hippocampal CA3 pyramidal neurons were assayed quantitatively, and the NO - 2/NO - 3 level of hippocampal homogenate was also measured using nitric acid deoxidize enzyme method. RESULTS: The nNOS average grey degree of hippocampal CA3 pyramidal neurons was significantly lower in stress group (155 42?3 77)than that in control group(164 54?4 62)and in stress plus phenytoin group(164 27?2 55)( P