AEPs were recorded at 1046 paramedian midbraih sites in 31 cats of both sexes when electrical stimulations were applied to 46 points within the HVMs after the cats had been anesthetized with nembutal and paralyzed with flaxedil. In the 103 responsive sites where AEPs were recorded, 151 fast wave responses were obtained. When the HVM was stimulated with electrical pulses of increasing intensity, two types of midbrain responses were recorded:"graded" and "all or none". Responsiveness of AEPs was tested for using paired stimui (PST) of different frequencies. Of the 111 AEPs tested, 38 could follow PST above 500Hz, 27 between 200-499Hz, and 46 under 199Hz. In order to test the responsiveness of AEPs further, short trains of pulses were applied. The results suggested that there might be both transsynaptic and direct connections between the two brain regions. According to calculations,the conduction velocity over this path was about 0. 29-4. 1m/sec., similar to the conduction velocity in thin myelinated and nonmyelinated fibers of the peripheral nerve. On the basis of the electrophysiological and histological data, it is suggested that there might be a topographical organization between HVM and mesencephalic central gray in dorsal-dorsal ventral-ventral direction. Some characteristics of responses which may belong to central axons are described. Advantages of the method of combining PST test with short train test in the evaluation of responsveness of the neural tissues are discussed..

In 23 cats of either sex anesthetized with nembutal, the AEPs(Averaged evoked potentials) were recorded in the paramedian midbrain area which either the HDM (Hypothalamic dorsomedial nucleus) or HP (Posterior hypothalamic nucleus) or HL (Lateral hypothalamic nucleus) and nearby structures were being stimulated. The responsive characteristics of the AEPs were tested with PST (Paired Stimuli) of defferent frequenencies. It was found that there are "spike-like" responses and "slow wave" in the cat's midbrain during hypothalamic stimulation . According to its responsiveness to electrical stimuli of increasing strength, the AEPs could be classified into two types: "graded" and "all or none" like. Of 75 AEPs elicited by stimulating the HDM, 24 could follow a PST with a freqency of more than 500Hz, 31 a PST with a frequency of 200-499Hz and 20 a PST with a frequency of less 199Hz. The midbrain responsive loci were mainly distributed in an area including central gray and adjacent tegmentum,but seldom in the tectum. On the basis of calculation of the conduction distance between the stimulating and recording sites and that of ahe latency of the response which could follow a PST with more than 500Hz, the conduction velocity over the path was estimated to be about 0.65-8.18m/sec., which was in the range of conduction velocity of thin myelinated and nonmyelinated fibers in the peripharal nerve. Results of the similar kind were obtained with HP or HL stimulations.But HL-MFB(medial forebrain bundle) stimulations elicited a AEP with a longer duration. These results were in agreement with those abtained in the rat, they showed some responsive characteristics belonging to the cat's brain, i.e. the wider spectrum of conduction velocity, the more restricted area for the appearance of a given midbrain response, and the predominant distribution of responsive loci within the central gray and ventral tegmentum adjacent to it.

To evaluate the role of the vagal afferents in the generation and formation of high frequency oscillation (HFO), effect of selective electrical stimulation of A?-? afferent fiber groups of the vagus nerve (0.4-0.5 V, 0.1ms, 5-160 Hz), applied at three respiratory phases: inspiratory phase (IS), expiratory phase (ES), and continuous phase throughout both IS and ES (CS), on the phrenic HFO was quantitatively assessed on ether-anesthetized, vagotomized, paralyzed and artificially ventilated rabbits. After calculation of the power spectrum of the efferent phrenic nerve activity, the mean square values (MSV), representing total amount of HFO-output, and the peak frequency of the HFO were estimated by means of curve-fitting method. Regardless of the mode of the stimulation, the MSV decreased in a stimulus-frequency dependent fashion. The CS was most potent, then IS, and ES was less effective, though the reduction was significant (p

The second class is not only a useful supplement to the first class but also an effective way to improve the comprehensive quality and ability of students.Through the deliberate research training and laboratory work,the second class of scientific research facilitates the medical students' developing scientific thinking,expanding professional knowledge,enhancing the ability to do scientific research and cultivating the spirit of teamwork.

ObjectiveTo evaluate the attachment type,the level of alexitymia and the defense style of depression patients and their relativity.Methods 32 depression patients were assessed with the adult attachment scale (AAS-1996 Revised Edition),toronto alexithymia scale (TAS) and defense style questionnaire( DSQ),and 80 healthy people were involved as controls.Results The depression patients showed significantly different attachment type from the control group( x2 =47.6,P ＜ 0.01 ).Compare with the control group,the depression patients showed higher scores in immature defense style( (5.47 ± 1.13 ) vs (3.79 ± 1.09 ) ) and neurotic defense style( (4.93 ±0.56) vs (4.20 ± 1.00),(P＜0.01) ).Compared with controls,the depression patients showed higher scores in TAS total score( (76.88 ± 8.94) vs (65.70 ± 7.98 ) ) factor Ⅰ ( ( 3.34 ± 0.77 ) vs ( 2.41 ±0.78)) and factor Ⅱ ((3.64 ±0.51) vs (2.65 ±0.55),P＜0.01),and lower scores in factor Ⅲ((2.51 ±0.78) vs (3.14 ± 1.03 ),P ＜ 0.01 ).The depression patients' adult attachment was significantly correlative with their scores of alexithymia.The depression patients' adult attachment was also significantly correlative with their scores of defense style.ConclusionThe attachment of depression patients may lead to depression via their defense style.Depression leads to alexitymia.Depression patients with different features of attachment show different level of alexitymia.

Objective To establish the extraction process of Zhechong Chuangyu Capsule. Methods The difference of analgesic effect of water extraction and alcohol extraction in mice was observed by body-torsion test to determine the extract solvent. With the rate of aqueous extraction, n-butyl alcohol extraction and asperosaponin Ⅵ as evaluating indicator, the influencing factors including solvent volume, time and times of extraction were investegated to evaluate extracting procedure by orthogonal experiment. Results There was no obvious difference in analgesic effect between water extraction and alcohol extraction. Given the requirement of produce, aqueous extraction was a better choice. The optimum extracting condition was extracted 3 times with 20 folds volume of solvent, and extraction time was 150 minutes. Conclusion The extraction process is feasible to be applied into production.

0.05), but completely (3 neurons) or partially (9 neurons) blocked the excitatory effect induced by CORT. CONCLUSION CORT had rapid excitatory effects on the Caldiovascular neuronsin the RVLM. RU 486 had no responses to the baseline activity of the cardiovascular neurons, and but completely or partially blocked the effect of CORT on the cardiovascular neurons.

AIM　To study the roles of non-genomi c mechanism of glucocorticoid in the integration of sympathetic nervous system. METHODS　The spontaneous discharge of the identified cardiovascula r neurons in the rostral ventrolateral medulla (RVLM) were extracellularly recor ded in urethane-anaesthetized rats. The effects of microiontophoresis of cortic ostersone sulfate (CORT) on the discharge of the cardiovascular neurons in the RVLM were observed. The responses of RU 486 (a blocker for cytosolic glucocortic oids) to the effects of CORT on the cardiovascular neurons were investigated. RESULTS　Totally 33 cardiovascular neurons in the RVLM were recorded , the firing rate of 25 (76%) cardiovascular neurons increased by microiontophor esis of CORT. The effects of CORT were also positively correlated with the curre nt. In 8 (24%) cardiovascular neurons, microiontophoresis of CORT had no effect on their spontaneous discharge. In 12 of 33 cardiovascular neurons, which discha rge increased by CORT, microiontophoresis of RU 486 had no responses to the base line discharge of these cardiovascular neurons (P>0.05), but completely (3 neurons) or partially (9 neurons) blocked the excitatory effect induced by CORT. CONCLUSION　CORT had rapid excitatory effects on the cardiovascul ar neurons in the RVLM. RU 486 had no responses to the baseline activity of the cardiovascular neurons, and but completely or partially blocked the effect of CO RT on the cardiovascular neurons.

Objective: To study the role of glucocorticoid i n the integration of sympathetic nervous system and cardiovascular activity. Methods: Neurons in the rostral ventrolateral medulla (RVLM) were extracelluarly recorded and identified as the presympathetic neurons of adult rats. The spontaneous discharge of the presympathetic neurons in the RVLM were observed by bolus intravenous injection of corticosterone (50, 100, 150 μg/kg） . Results: The firing rate of 12 presympathetic neurons was incr eased by intravenous application of corticosterone (P<0.05), and this effect showed a dose-dependent manner. The latency of excitatory effect was (104±2 5) s. Conclusion: Corticosterone can rapidly excite the presym pathetic neurons in the RVLM, this action might be involved in the integration o f sympathetic nervous system through the “rapid membrane effects”.

Replenishing the insulin-producing β cell mass is considered to be a hot topic in the field of diabetes treatment.It has long been known that pancreatic β cells are generated primarily by self-duplication in adults.However,insulin resistance can induce dramatic compensatory β cell mass expansion in the pancreas.Therefore,it is of great value to investigate the etiology and pathogenesis of β cell proliferation under insulin resistance.The recent study has shown that betatrophin,a protein secreted by the liver,modulates β cell growth in response to insulin resistance.We published one article in Diabetes Care titledIncreased circulating levels of betatrophin in newly diagnosed type 2 diabetic patientsto elaborate the relationship between diabetes and betatrophin.