Tissue factor pathway inhibitor inhibits aortic smooth muscle cell migration induced by tissue factor/factor VIIa complex

Tissue factor (TF), a transmembrane glycoprotein, forms a high affinity complex with factor VII/VIIa (FVIIa) and thereby initiates blood coagulation. Tissue factor pathway inhibitor (TFPI) is an endogenous protease inhibitor of TF/FVIIa-initiated coagulation. We previously reported that TF was a strong chemotactic factor for cultured vascular smooth muscle cells (SMCs). In this study, we examined the contribution of FVIIa and the effect of TFPI to TF-induced cultured SMC migration. TF/FVIIa complex showed a strong migration ability, however, neither TF alone nor FVIIa induced SMC migration. TF/FVIIa treated by a serine protease inhibitor and the complex of TF and inactivated FVIIa (DEGR-FVIIa) did not stimulate SMC migration. Pretreatment with hirudin and the antibodies to alpha-thrombin and factor X had no effect on TF/FVIIa-induced SMC migration, although alpha-thrombin and factor Xa also induced SMC migration respectively. TFPI markedly inhibited TF/FVIIa-induced SMC migration in a concentration-dependent manner, but did not affect the SMC migration induced by platelet-derived growth factor (PDGF)-BB, basic fibroblast-growth factor (bFGF), or alpha-thrombin. These results indicate that the catalytic activity of TF/FVIIa complex is important on SMC migration, and TFPI can reduce SMC migration as well as thrombosis.

Clinicopathological significance of epidermal growth factor and its receptor in human pancreatic cancer

The expression of epidermal growth factor (EGF) and its receptor (EGF-R) was examined immunohistochemically in 60 primary and 26 metastatic lesions of pancreatic carcinoma. EGF was stained mainly in the cytoplasm of tumor cells, and EGF-R was stained mainly on the surface of cells. The expression rates of EGF and EGF-R were 28% and 43% for primary lesions, and 46% and 46% for metastatic lesions, respectively. The expression of EGF and EGF-R alone did not correlate with any clinicopathological factors such as clinical stage, tumor size, nodal involvement, histology, etc. The median survival period after pancreatectomy was 21.4 months for patients with EGF(+) cancers and 25.1 months for those with EGF (-) ones. On the other hand, the median survival period was 22.7 months for patients with EGF-R (+) cancers and 25.0 months for those with EGF-R (-) cancers. There were no significant differences in survival between groups of patients differing in EGF or EGF-R expression. When the expression of EGF and EGF-R was analysed in combination, the survival curve of patients with EGF(+) and EGF-R(+) cancers was found to be lower than that of the rest of the patients (p = 0.07), and especially the survival curve of patients with EGF(+)EGF-R(+) cancers was significantly lower than that of patients with EGF(+)EGF-R(-) cancers (p = 0.02), and EGF(-)EGF-R(+) cancers (p = 0.06). These results indicate that the expression of EGF or EGF-R alone in pancreatic cancer does not reflect the prognosis of patients; however the coexpression of EGF and EGF-R may be a beneficial prognostic factor for pancreatic cancer.

Human T-cell lymphotropic virus type 1 can infect primary rat retinal glial cells and induce gene expression of inflammatory cytokines

PURPOSE

To examine whether or not retinal glial cells can be infected by human T-cell lymphotropic virus type 1 (HTLV-1) and test the possibility that HTLV-1-infected retinal glial cells are involved in the pathogenesis of HTLV-1 uveitis (HU).

METHODS

We tested infection of HTLV-1 by a standard coculturing method using WKAH rat retinal glial cells and irradiated MT-2, a human T cell line that produces HTLV-1. Infection was confirmed by detecting the integrated HTLV-1 provirus, using polymerase chain reaction (PCR), viral gene expression, using reverse transcriptase-PCR (RT-PCR) and HTLV-1 p19 ELISA, and by identifying the HTLV-1-infected glial cells by immunofluorescence cytochemistry and in situ hybridization. Changes in cytokine gene expression were studied by RT-PCR.

RESULTS

Using a semiquantitative PCR of HTLV-1 provirus sequence, we found that 2.6% of the retinal glial cells were infected at 3 days after infection, followed by a gradual decrease in the percentage with an extended period of culture up to 4 weeks. This time course of infection was also verified by RT-PCR and ELISA studies that detect viral mRNA expression and protein production, respectively. Expression of HTLV-1 gag protein and tax mRNA was detected in a part of glial cells by indirect immunofluorescence cytochemistry and in situ hybridization, respectively. RT-PCR analysis of cytokine gene expression revealed that gene expression of IL-6, CINC-1 (Gro, KC), and TNF-alpha were induced in these cells, with a peak at 3 weeks after infection.

CONCLUSION

These results provided supportive evidence for the theory that the infection of retinal glial cells by HTLV-1 and subsequent production of inflammatory cytokines could be one contributing factor for the development of the unique clinical features of HU. A better understanding of the specific roles of the inflammatory cytokines in the pathogenesis of HU would be beneficial in the treatment and control of this disease.

Insulinoma in a patient with non-insulin-dependent diabetes mellitus

Insulinoma in a patient with pre-existing diabetes is exceedingly rare. Only a small number of well-documented cases have been reported in the world during the last 40 years. We describe a case with non-insulin-dependent diabetes mellitus who after seven years of sulfonylurea treatment experienced recurrent episodes of hypoglycemia. Endogenous hyperinsulinism was found and radiographical examination and transhepatic venous sampling confirmed an insulin secreting pancreatic tumor. After surgical excision of the tumor, patient was relieved from hypoglycemic attacks but required to initiate insulin injection for the treatment of hyperglycemia.

[New aspects in the liver regeneration following partial hepatectomy]

We demonstrated the new two concepts for the liver regeneration after partial hepatectomy (PHx). The first is immunological findings in the regenerating liver. Th1 type T cells, which produce IFN gamma, and extrathymic T cells may play an important role in immunological control system of liver regeneration after PHx on the basis of the cellular immunity restricted by MHC class I and II molecules. The second is the mechanism of "on and off" on liver regeneration after PHx. Portal pressure, which reflecting wall shear stress of sinusoid, may trigger the liver regeneration and control the liver volume after PHx. There are two type of intrahepatic leukocytes; one type would tend to stay associated with SEC, while the other would not. Therefore shear stress may have a great influence on the leukocytes-sinusoidal endothelial cells (SEC) adhesion immediately after partial hepatectomy.

HMG-CoA reductase inhibitors suppress macrophage growth induced by oxidized low density lipoprotein

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors ameliorate atherosclerotic diseases in several models of vascular disease. This is largely due to their ability to reduce plasma cholesterol levels in vivo. Proliferation of cellular components is one of the major events in the development and progression of atherosclerotic lesions. We recently demonstrated that oxidized low density lipoprotein (Ox-LDL), a likely atherogenic lipoprotein present in vivo, is capable of inducing macrophage growth in vitro. In the present study, we investigated the effect of HMG-CoA reductase inhibitors, simvastatin and pravastatin, on Ox-LDL-induced macrophage growth. Our results demonstrated that these inhibitors effectively suppressed Ox-LDL-induced macrophage growth with concentrations required for 50% inhibition by simvastatin and pravastatin being 0.1 and 80 microM, respectively, and that this inhibitory effect was reversed by mevalonate but not by squalene. Under these conditions, simvastatin did not affect the endocytic degradation of Ox-LDL, nor subsequent accumulation of intracellular cholesteryl esters. Our results suggest that a non-cholesterol metabolites(s) of mevalonate pathway may play an important role in Ox-LDL-induced macrophage growth. Since it is well known that macrophage-derived foam cells are the key cellular element in the early stage of atherosclerosis, a significant inhibition of Ox-LDL-induced macrophage growth by HMG-CoA reductase inhibitors in vitro, particularly simvastatin, may also explain, at least in part, their anti-atherogenic action in vivo.

Predictors of sinus rhythm restoration after Cox maze procedure concomitant with other cardiac operations

BACKGROUND

There have been sporadic cases of persistent atrial fibrillation and sick sinus syndrome after the maze procedure. The purpose of this study was to identify the predictors of sinus rhythm restoration after operation.

METHODS

Between March 1993 and June 1995, we evaluated retrospectively 96 consecutive patients who underwent the maze procedure (maze III) in combination with another type of cardiac operation. Four patients who died and 6 patients who required permanent pacemaker implantation because of sick sinus syndrome were excluded. Ambulatory electrocardiographic monitoring was evaluated 1 year after operation. Multiple logistic regression analysis was applied to identify the predictors of sinus rhythm restoration.

RESULTS

The final population comprised 86 patients (mean age, 59.8 years; 67 patients with mitral valve disease). Overall, sinus rhythm was restored in 68 of 86 patients (79.1%). The magnitude of the atrial fibrillatory wave positively predicted postoperative sinus rhythm restoration. Conversely, left atrial diameter was inversely related to postoperative sinus rhythm restoration. The odds ratio of having both a fine atrial fibrillatory wave (< 1.0 mm) and enlarged left atrial diameter (> or = 65 mm) for patients with sinus rhythm restoration was 0.04 (95% confidence interval, 0.01 to 0.28).

CONCLUSIONS

Atrial fibrillatory wave and left atrial diameter were independent predictors of sinus rhythm restoration after the maze procedure in patients with chronic atrial fibrillation and organic heart disease.

Cystic metacestodes of a rat-adapted Taenia taeniaeformis established in the peritoneal cavity of scid and nude mice

In vitro-hatched (but not activated) oncospheres of a rat-adapted strain of Taenia taeniaeformis intraperitoneally inoculated into severe combined immunodeficiency (scid), congenitally athymic (nude) and immunocompetent (normal) female BALB/c mice developed into cystic metacestodes in the peritoneal cavity (but not in the liver) of scid and nude mice exclusively. This suggests that cystic metacestodes of this parasite, usually harboured in the liver only, can establish in scid and nude mice provided that the oncospheres are inoculated into the peritoneal cavity. Immunodeficient mice, especially scid mice, may be a good experimental animal model for the intermediate host of any taeniid species, of human, domestic- or wild-animal origin.

Immunostimulatory DNA sequences function as T helper-1-promoting adjuvants

An adjuvant role for certain short bacterial immunostimulatory DNA sequences (ISSs) has recently been proposed on the basis of their ability to stimulate T helper-1 (Th1) responses in gene-vaccinated animals. We report here that noncoding, ISS-enriched plasmid DNAs or ISS oligonucleotides (ISS-ODNs) potently stimulate immune responses to coadministered antigens. The ISS-DNAs suppress IgE synthesis, but promote IgG and interferon-gamma (IFN-gamma) production. They furthermore initiate the production of IFN-gamma, IFN-alpha, IFN-beta, and interleukins 12 and 18, all of which foster Th1 responses and enhance cell-mediated immunity. Consideration should be given to adding noncoding DNA adjuvants to inactivated or subunit viral vaccines that, by themselves, provide only partial protection from infection.

A novel DNA polymerase in the hyperthermophilic archaeon, Pyrococcus furiosus: gene cloning, expression, and characterization

BACKGROUND

In many respects Archaea are much more like eukaryotes than prokaryotes with respect to the conservation of many of the components involved in transcription, translation and DNA replication. So far, only a few DNA polymerases with structures similar to those of eukaryotic DNA polymerase a have been found in Archaea. The identification and characterization of all the DNA polymerases of one archaeon would add considerably to our knowledge of the basic mechanisms of DNA replication in these organisms.

RESULTS

We have identified a novel DNA polymerase composed of two proteins, DP1 and DP2, with molecular weights of 69294 Da and 143161 Da, respectively, in the hyperthermophilic archaeon, Pyrococcus furiosus, and have cloned the corresponding genes which are tandemly arranged on the Pyrococcus genome. No significant sequence homology was found between these two proteins and other known DNA polymerases. The pol genes were transcribed as part of a single operon that additionally contained genes homologous to the cdc18+/CDC6 and Dmc1/Rad51 family of proteins. We purified the Pyrococcus DNA polymerase from Escherichia coli strains expressing the cloned genes and characterized its activity. It possesses strong 3' --> 5' exonucleolytic activity and has a template-primer preference which is characteristic of a replicative DNA polymerase.

CONCLUSION

In P. furiosus, we identified a second DNA polymerase encoded by two genes, neither of which display significant homology to any other known DNA polymerase. Both the enzymatic properties of the enzyme and the gene organization raise the possibility that this enzyme might be the replicative DNA polymerase of P. furiosus.

Long-term effects of water-soluble corn bran hemicellulose on glucose tolerance in obese and non-obese patients: improved insulin sensitivity and glucose metabolism in obese subjects

We examined the effect of soluble corn bran hemicellulose (CBH, 10 g/day) on glucose control and serum insulin in three groups: patients with impaired glucose tolerance (IGT) with (20 subjects) or without (8 subjects) obesity and with healthy non-obese controls (10 subjects). Long-term supplementation (6 months) with CBH decreased the post oGTT curve for patients with impaired mild Type II diabetes, but not that for the controls. Hemoglobin A1c decreased significantly during CBH supplementation in the obese patients, while the fasting glucose level decreased in all three groups, although not significantly. A decreased serum insulin response by oGTT was found in those patients with IGT. The improved oGTT result was associated with improved insulin release and perhaps with peripheral insulin sensitivity. These findings suggest that CBH at a low dose might contribute to glycemic control and would play a useful role in treating Type II diabetes patients.

High-energy defibrillation increases the severity of postresuscitation myocardial dysfunction

BACKGROUND

The fatal outcome of victims after initially successful resuscitation from cardiac arrest has been attributed both to global myocardial ischemia during the interval of cardiac arrest and to the adverse effects of reperfusion. The present study was prompted by earlier experimental observation that the magnitude of myocardial dysfunction was in part related to the energy delivered during electrical defibrillation.

METHODS AND RESULTS

Ventricular fibrillation (VF) was induced in 15 Sprague-Dawley rats. Precordial compression was begun together with mechanical ventilation after 4 minutes of untreated VF and continued for 6 minutes. Spontaneous circulation was restored in each animal after external defibrillation with a single stored 2-, 10-, or 20-J countershock. Cardiac index and the rate of left ventricular pressure rise at left ventricular pressure of 40 mm Hg (dP/dt40) and fall (negative dP/dt) during the 240-minute interval after successful resuscitation were decreased, and left ventricular diastolic pressure was increased. These decreases in myocardial function were closely related to the energy of electrical defibrillation. After a 20-J shock, animals survived for only 5+/-3 hours; after a 10-J shock, animals survived for 15+/-4 hours; and after a 2-J shock, all animals survived for >24 hours.

CONCLUSIONS

The severity of postresuscitation myocardial dysfunction is related, at least in part, to the magnitude of the electrical energy of the delivered shock.

p53 protein expression as prognostic factor in human pancreatic cancer

Mutations in the p53 tumor suppressor gene are considered to play an important role in the carcinogenesis of pancreatic cancer. The present study was designed to assess the clinicopathological significance of the expression of p53 protein in human pancreatic cancer. A total of 64 specimens of pancreatic cancer (44 primary and 20 metastatic lesions) were obtained by surgery in our department between 1982 and 1995, and p53 protein was stained using an immunohistochemical staining method (strepto-avidin-biotin complex method) with 2 kinds of anti-p53 monoclonal antibodies (DO-1 and PAb240). DO-1-p53 was usually stained in the nucleus of cancer cells and was positively expressed in 35 out of 64 specimens (54.7%): 21 out of 44 primary lesions (47.7%), and 14 out of 20 metastatic lesions (70.0%). On the other hand, PAb240-p53 was stained in both the nucleus and cytoplasm in 45 out of 64 specimens (70.3%): 33 out of 44 primary lesions (75.0%) and 12 out of 20 metastatic lesions (60.0%). The survival rate of the patients with DO-1-p53 (+) pancreatic cancer after pancreatectomy was significantly lower than that of patients with DO-1-p53 (-) pancreatic cancer. On the other hand, there were no significant implications of PAb240-p53 protein expression on survival after pancreatectomy. With regard to the clinicopathological characteristics, the rate of DO-1-p53 protein expression was significantly higher in elderly patients (> or = 65 y.o.). As a result, DO-1-p53 protein expression may be a beneficial prognostic factor for patients with pancreatic cancer, and it is a factor independent of the stage and other clinicopathological factors.

Role of cytoprotective mechanisms in the photochemical purging of autologous bone marrow grafts

The molecular basis of the differential sensitivity of normal hematopoietic stem cells and of leukemia, lymphoma, and neuroblastoma cells to merocyanine 540 (MC540)-mediated photodynamic therapy (PDT) is not yet completely understood. While the capacity to bind dye molecules appears to be the major determinant of a cell's susceptibility of MC540-mediated PDT, we here present evidence that under certain experimental conditions a cell's capacity to repair MC540-mediated photodynamic damage is also an important factor. Two parameters, temperature and intracellular glutathione (GSH) content, were varied to investigate the role of cellular defense mechanisms in the dye-sensitized photoinactivation of normal murine granulocyte/macrophage progenitors (CFU-GM) and K562, L1210, and melphalan-resistant L1210/L-PAM1 leukemia cells. When exposed to MC540 and light at room temperature, the three leukemia cell lines bound similar amounts of dye and accumulated similar amounts of lipid hydroperoxide (LOOH) but differed markedly in their sensitivity to MC540-mediated PDT. Performing MC540-mediated PDT at 4 degrees C instead of at room temperature reduced dye binding and LOOH generation and enhanced cytotoxicity in some but not all cell lines. A brief (< or = 120 minutes) incubation at 37 degrees C immediately following MC540-mediated PDT accelerated the decay of LOOH in all leukemic cell lines and reduced cell kill by about 2 log in both CFU-GM and leukemia cells. The effect of post-PDT incubation at 37 degrees C on LOOH decay was most pronounced in K562 and least pronounced in L1210/L-PAM1 cells, whereas its effect on cell survival was less pronounced in L1210 cells than in the remaining cell types. L1210/L-PAM1 cells whose GSH content had been reduced from 8.2 to 1.6 micrograms/mg protein by incubation with buthionine sulfoximine recovered from potentially lethal photodynamic damage as rapidly as untreated L1210/L-PAM1 cells and more rapidly than wild-type L1210 cells with a GSH content of 4.5 micrograms/mg protein. Thus, with regard to capacity of L1210/L-PAM1 cells to recover from photodynamic damage, the cells' enhanced capacity to synthesize GSH appeared more decisive than intracellular GSH levels per se. Taken together, these data suggest that temperature-dependent cellular defense mechanisms are significant determinants of a cell's susceptibility to MC540-mediated PDT. The data emphasize the need for temperature control during and immediately after the photochemical purging of autologous bone marrow or peripheral blood stem cells.

Effect of friction coefficient on Akers clasp retention

STATEMENT OF PROBLEM

Retentive force control of clasp retainers is one of the most essential factors for the successful function of removable partial dentures. However, it is not yet known how the friction coefficients differ among restored abutments and clasp materials, and how the friction coefficients affect the retention of clasps.

PURPOSE

The purposes of this study were to clarify the friction coefficients among restored abutments and clasp materials and to estimate the effect of friction coefficients on the retention of clasps.

MATERIAL AND METHODS

The coefficients of static friction between three clasp materials (type IV gold, high Pd, and cobalt-chromium [Co-Cr] alloys) of two surface treatments (polished and sandblasted) and four abutment materials (human enamel, porcelain, type IV gold, and high Pd alloys) were evaluated under three conditions (dry, wet with water, and wet with saliva), and theoretically, the effect of the friction coefficients on clasp retention was estimated.

RESULTS

The friction coefficients under various conditions ranged from 0.08 (polished Co-Cr clasp on type IV abutment in dry condition) to 0.37 (sandblasted Co-Cr clasp on high Pd abutment in dry condition). The theoretical estimation clarified that the retentive force of the clasp was linear to the friction coefficient.

CONCLUSION

The retentive force increased linearly with increasing friction coefficient between abutment material and clasp material according to the newly developed formula. This study suggested that clasp designs should be changed depending on abutment materials.

Spiral computed tomography with 3-dimensional reconstruction for the diagnosis of tracheobronchial stenosis

We report on the usefulness of spiral computed tomography (CT) with 3-dimensional (3D) reconstruction in the diagnosis of tracheobronchial abnormalities based on three cases of children with congenital tracheobronchial strictures. Images were reconstructed using a curved planar reformat and shaded surface display. The images obtained from our three cases of tracheal stenosis, subglottic stenosis and tracheobronchial strictures were extremely clear. Spiral CT with 3D reconstruction provides excellent anatomic delineation of the tracheobronchial airway, and is safe and less invasive than tracheobronchography.

CP2289, a new 5-HT3 receptor ligand: agonistic activities on gastroenteric motility

A new 5-HT3 receptor ligand, CP2289, was synthesized and pharmacologically tested. Although CP2289 inhibited the Bezold-Jarisch reflex, it contracted the excised ileal muscle of mice, rats and guinea pigs. This response may reflect a partial agonist character of CP2289 in the gut. In vivo antiemetic and gastric emptying tests gave similar results.

Differential contribution of two serine residues of wild type and constitutively active beta2-adrenoceptors to the interaction with beta2-selective agonists

1. We have studied the difference in receptor binding activity between partial and full beta2-adrenoceptor agonists and the abilities of the agonists to interact with Ser204 and Ser207 in the fifth transmembrane region of the beta2-adrenoceptor, amino acid residues that are important for activation of the beta2-adrenoceptor. 2. In the binding study with [125I]-iodocyanopindolol, the Ki values of (+/-)-salbutamol, (+/-)-salmeterol, TA-2005 and (-)-isoprenaline for the beta2-adrenoceptor expressed in COS-7 cell membranes were 3340, 21.0, 12.0 and 904 nM, respectively. The beta1/beta2 selectivity of these agonists was in the order of (+/-)-salmeterol (332 fold) > TA-2005 (52.8) > (+/-)-salbutamol (6.8) > (-)-isoprenaline (1.1), and the beta3-/beta2-adrenoceptor selectivity of these agonists was in the order of TA-2005 (150 fold) > (+/-)-salmeterol (88.6) > (+/-)-salbutamol (10.4) > (-)-isoprenaline (3.2). 3. The maximal activation of adenylyl cyclase by stimulation of the beta1-, beta2- and beta3-adrenoceptors by TA-2005 was 32, 100 and 100% of that by (-)-isoprenaline, respectively, indicating that TA-2005 is a full agonist at the beta2- and beta3-adrenoceptors and a partial agonist at the beta1-adrenoceptor. (+/-)-Salbutamol and (+/-)-salmeterol were partial agonists at both beta1- (8% and 9% of (-)-isoprenaline) and beta2- (83% and 74% of (-)-isoprenaline) adrenoceptors. 4. The affinities of full agonists, TA-2005 and (-)-isoprenaline, were markedly decreased by substitution of Ala for Ser204 (S204A) of the beta2-adrenoceptor, whereas this substitution slightly reduced the affinities of partial agonists, (+/-)-salbutamol and (+/-)-salmeterol. Although the affinities of full agonists for the S207A-beta2-adrenoceptor were decreased, those of partial agonists for the S207A-beta2-adrenoceptor were essentially the same as for the wild type receptor. 5. The constitutively active mutant (L266S, L272A) of the beta2-adrenoceptor had an increased affinity for all four agonists. The affinities of full agonists were decreased by substitution of Ser204 of the constitutively active mutant, whereas the degree of decrease was smaller than that caused by the substitution of the wild type receptor. Although the affinities of (+/-)-salbutamol and (+/-)-salmeterol for the S207A-beta2-adrenoceptor were essentially the same as those for the wild type beta2-adrenoceptor, the affinities of (+/-)-salbutamol and (+/-)-salmeterol for the constitutively active beta2-adrenoceptor were decreased by substitution of Ser207. 6. These results suggest that Ser204 and Ser207 of the wild type and constitutively active beta2-adrenoceptors differentially interacted with beta2-selective agonists.

Neural mechanism of pupillary dilation elicited by electro-acupuncture stimulation in anesthetized rats

The neural mechanisms to reflex dilation elicited by electro-acupuncture stimulation were investigated in anesthetized rats. Two needles, with 160 microns diameter and about 5 mm apart, were inserted into the skin and underlying muscle of a hindpaw. Repetitive 20 Hz, 0.5 ms electrical pulses at various intensities were used for stimulation for 30s. The pupil size was magnified about 44 times via a microscope and was continuously recorded on a videotape. Electro-acupuncture stimulation at more than 0.5 up to 6 mA induced stimulus intensity-dependent pupil dilation. These responses were abolished by the severance of the sciatic and saphenous nerve of the stimulated hindlimb. Compound action potentials were recorded from the distal cut end of the tibial of a saphenous nerve following electro-acupuncture stimulation of the hindpaw. The mean threshold of the compound action potentials of the myelinated fibers in saphenous nerves was 0.18 mA, while that of unmyelinated fibers was 3.0 mA. The mean threshold of the compound action potentials of the myelinated fibers in the tibial nerve was 0.20 mA of unmyelinated fibers was 3.3 mA. Severance of bilateral trunks did not affect the response, while severance of the third cranial nerves abolished the responses. In conclusion, electro-acupuncture stimulation applied to the hindpaws of the anesthetized rats induced excitation of myelinated or of both myelinated and unmyelinated afferent fibers of the tibial and saphenous nerve, and involved a reflex response of pupil dilation through the third cranial parasympathetic efferent nerve.