[Effects of space flight on medicinal plant Agastache rugosa (Fisch. et Mey.) O. Ktze]

OBJECTIVE

To substantiate the effect of space conditions on medicinal plants.

METHODS

The seeds of Agastache rugosa were set up in retrievable satellites. After returning to earth, the changes of isozymes of peroxidases, esterase and soluble proteins were studied.

RESULTS

The peroxidase activity and protein content of the weightless group were a little lower than those of the earth controlled group, while these two items of the hit group were higher than those of the earth controlled group. The electrophoresis patterns of isoperoxidases and isoeasterase of these three groups, as well as the protein patterns of the weightless group and the earth controlled group were found alike. But the protein patterns of the hit group were different from those of the other two groups.

CONCLUSION

The effect of weightlessness is smaller than that of the high energy heavy ions on Agastache rugosa. Different plants have different susceptibility to space conditions.

Distribution of SPR-like immunoreactivity in the medullary visceral zone of the rat and changes following acute myocardial ischemia induced by intravenous injection of vasopressin

Substance P receptor-like immunoreactive (SPR-LI) structures and changes following intravenous injection of vasopressin in the medullary visceral zone (MVZ) of the rat were studied by using immunohistochemical methods. In normal control rats the distribution of SPR-LI structure in MVZ generally matched with that of immunostaining against substance P (SP-LI) except in some areas. SPR-LI neurons and dendrites differed in size and shape in different areas of MVZ. Their dendrites could be classified into three types, i.e, wool-shaped, smooth and varicose. Some SPR-LI neurons were also positive for tyrosine hydroxylase-like immunoreactivity (TH-LI) . After administration of vasopressin SPR-LI structures became denser, especially at levels of pyramidal decussation (PYX) and area postrema (AP). The dendrites of motor dorsal nucleus of X (NMDX) in the dorsal part of MVZ appeared thin and straight in morphology instead of curl and thick outlooks. These results implicate that some SPR-LI neurons might be involved in the modulation of the cardiovascular stress induced by vasopressin.

Retrograde embolization during saphenous vein graft angioplasty

Angioplasty of degenerated saphenous vein grafts is not infrequently complicated by distal embolization of atheromatous debris. We describe an uncommon case in which balloon angioplasty of an old vein graft to a second diagonal branch of the left anterior descending coronary artery was followed by distal embolization. However, the embolization occurred in a retrograde fashion distal to the anastomotic site, resulting in occlusion of the upstream first diagonal branch. The reasons for its occurrence are discussed, together with suggestions for its recognition.

[Effect of space environment on physiological state in Carthamus tinctorius L]

OBJECTIVE

To substantiate te effect of weightlessness and heavy ion radiation in space environment on medicinal plants.

METHODS

The seeds of medicinal plant Carthamus tinctorius were carried aboard a retrievable satellite during 3-18 July, 1994. After returning to earth, the changes of peroxidase and protein were studied by means of electrophoresis.

RESULTS

The result showed that the peroxidase activity of each group of seeds which were hit and penetrated by heavy ions rays was higher than that of the ground controlled seeds, but slightly lower than that of the weightless seeds. The protein contents of the weightless seeds and the seeds which is penetrated once and less than once by heavy ions rays were higher than those of the seeds which were kept on earth, but the seeds which were penetrated 2-3 times by heavy ion rays were lower than those of the ground controlled seeds. The peroxidase isozyme and protein patterns of the weightless seeds were similar to those of the ground controlled seeds, but very different between the heavy ion ray penetrated seeds and the earth kept seeds.

CONCLUSION

It follows that the weightlessness in space environment has an effect mainly on the physiological condition of plants, but the heavy ion radiation has a stronger effect on the hereditary basis of plants.

[The features of coronary angiography in coronary heart disease with non-insulin-dependent diabetes mellitus]

OBJECTIVE

To study the clinical and angiographical characteristics of coronary heart disease (CHD) in CHD patients with non-insulin-dependent diabetes mellitus (NIDDM).

METHODS

The study was carried out by case control analysis of the clinical manifestations and the data from cine selective coronary angiography.

RESULTS

CHD patients with NIDDM tended to have multiple cardiovascular risk factors. It is likely that NIDDM contributed more to dyslipidemia in the female than in the male. Unstable angina pectoris was found more frequently in CHD patients with NIDDM than in those without. The female CHD patients with NIDDM were more frequently afflicted with myocardial infarction. Moreover, CHD patients with NIDDM had much greater extent of coronary vessel involvement and more diffuse vascular lesion.

CONCLUSION

The clinical and angiographical findings are quite different in CHD patients with and without NIDDM. The lesions in the coronary arteries tend to be more severe and diffuse in patients with NIDDM.

[Analysis of mandibular movement and functional classification for malocclusion patients]

OBJECTIVE

To classify the paths of mandibular movements of patients with malocclusion.

METHODS

223 patients were examined clinically and mandibular Kinesiograph(MKG) was applied.

RESULTS

Each kind of malocclusion has its corresponding characteristic paths of mandibular movement. The paths of mandibular movements of patients with the same class of malocclusion are similar. It was also found that the mandibular movement was related not only with occlusion but also with jaws, muscles, and joints. Meanwhile, they affect each other.

CONCLUSION

Functional malocclusion classification includes functional class I, II, III and IV malocclusion.

[Effect of space environment on germination and vegetation growth in Carthamus tinctorius L]

OBJECTIVE

To substantiate the effects of space condition on medicinal plants.

METHOD

The seeds of medicinal plant Carthamus tinctorius were carried on board a retrievable satellite during 3-18 July, 1994. After returing to earth, the seedling rate, state of growth and development were observed.

RESULT

The seeding rates, plant heights and branch quantities of weightless seeds and the seeds which were penetrated once and less than once by the heavy ion rays were higher than those of the seeds which were kept on earth, but these indexes of the seeds which were penetrated 2-3 times by the heavy ion rays were higher than those of the ground controlled seeds.

CONCLUSION

Weightlessness and little penetration promote the growth and development of Carthamus tinctorius, but much penetration functions the other way round.

L-selectin and ICAM-1 mediate reperfusion injury and neutrophil adhesion in the warm ischemic mouse liver

Leukocytes recruited during ischemia-reperfusion to the liver are important mediators of injury. However, the mechanisms of leukocyte adhesion and the role of adhesion receptors in hepatic vasculature remain elusive. L-selectin may critically contribute to injury, priming adhesion for later action of intercellular adhesion molecule-1 (ICAM-1). Paired experiments were performed using mutant mice (L-selectin -/-, ICAM-1 -/-, and L-selectin/ICAM-1 -/-) and wild-type mice (C57BL/6) to investigate leukocyte adhesion in the ischemic liver. Leukocyte adhesion and infiltration were assessed histologically. Aspartate aminotransferase levels were significantly reduced (2- to 3-fold) in mutant vs. wild-type mice in most groups but most significantly after 90 min of partial hepatic ischemia. Leukocyte adhesion was significantly reduced in all mutant mice. Areas of microcirculatory failure, visualized by intravital microscopy, were prevalent in wild-type but virtually absent in L-selectin-deficient mice. After total hepatic ischemia for 75 or 90 min, survival was better in mutant L-selectin and L-selectin/ICAM-1 mice vs. wild-type mice and ICAM-1 mutants. In conclusion, L-selectin is critical in the pathogenesis of hepatic ischemia-reperfusion injury. Poor sinusoidal perfusion due to leukocyte adhesion and clot formation is a factor of injury and appears to involve L-selectin and ICAM-1 receptors.

Coronary angiographic characteristics in unstable angina pectoris

OBJECTIVE

To investigate the angiographic characteristics of coronary lesions in patients of different subgroups of unstable angina pectoris.

METHODS

Coronary angiograms and clinical manifestations were analysed on 388 patients.

RESULTS

Single-vessel disease was more common in new onset effort angina (69.64%) than in other subgroups (P < 0.05); triple-vessel disease and left main coronary artery disease appeared more frequently in patients with rest angina than in other subgroups (72.34% and 27.66% respectively, P < 0.05), so did complex lesions and type C lesions (36.07% and 60.64% respectively, P < 0.05). More than half of the culprit lesions in post-infarction angina were subtotal or total occlusions (53.12%), being more frequently found in this than in other subgroups (P < 0.05). Most of the patients with Prinzmetal variant angina had mild coronary lesions only. Coronary thrombi were found in 10.45% of the 388 patients; they were more frequent in patients with post-infarction angina (20.00%) than in the subgroups of new onset effort angina, aggravated effort angina and Prinzmetal variant angina (4.26%, 7.53% and 0% respectively, P < 0.05). Coronary thrombi were also more frequent in patients with chest pain at rest (16.39%) than in the subgroups of new onset effort angina and Prinzmetal variant angina (P < 0.05).

CONCLUSIONS

It is suggested that patients with angina at rest should be treated more intensively. Energetic anticoagulation treatment should be given to patients with post-infarction angina and angina at rest.

[The mechanisms of hyperhomocysteinemia in coronary heart disease]

OBJECTIVE

To identify hyperhomocysteinemia (HHe) as a new and independent risk factor for coronary heart disease (CHD).

METHODS

The association of coronary heart disease (CHD) and lipid, homocysteine (HCY) and the factors related to its metabolisms were examined. The mutation of the 677C-->T transition of MTHFR was determined by PCR-based assay. Whole blood and plasma folate (FA) and plasma vitamin B12(B12), as cofactors of those enzymes, were determined by radioimmunologic assay. Plasma HCY was determined by HPLC.

RESULTS

Patients with CHD confirmed by coronary angiography had increased plasma HCY concentrations (17.1 +/- 3.6 mumol/L, 7.6 +/- 1.2 mumol/L). In patients with MI, HPT and family history (FH) of CHD, plasma HCY increased significantly. Plasma HCY concentrations had significant non-linear inverse relation with plasma FA and B12 concentrations. Homozygous mutants showed higher plasma HCY concentrations. Patients with CHD had increased serum CHOL and VLDL levels, but plasma HCY concentrations were not correlated with serum lipid levels.

CONCLUSION

Hyperhomocysteinemia is an independent risk factor for coronary heart disease.

Generation of lipid free radicals by adherent leukocytes from transplanted rat liver

The production of free radicals in blood correlates with primary nonfunction of transplanted livers, but the source of the free radicals is unknown. The purpose of this study was to determine if adherent leukocytes in the transplanted liver are responsible for the radicals detected in blood. First, a new method to harvest adherent leukocytes from the liver without enzymatic digestion was developed and characterized by transplanting livers from ethanol-treated rats, which increases primary nonfunction, and from saline-treated controls. Free radicals were then detected in isolated leukocytes using the spin-trapping technique and electron spin resonance (ESR) spin spectroscopy. Livers were perfused with a balanced salt solution (200 ml), followed by a Ca(2+)-free solution containing EGTA and heparin (400 ml). Perfusion with Ca(2+)-free buffer removed greater than 90% of all adherent leukocytes from saline-treated livers and nearly 80% of all leukocytes from fatty livers without removing Kupffer cells. Transplanted fatty livers from rats given ethanol contained significantly more adherent leukocytes (5.0 x 10(7) cells/liver) than grafts from control donors (3.2 x 10(7) cells/liver) and almost double the number of adherent neutrophils and monocytes. Moreover, adherent white blood cells from transplanted livers produced the same three free radical species that have been detected previously in blood; however, cells from ethanol-treated livers produced about five times more radical adducts. These data show that adherent white blood cells produce free radicals that are important in the mechanism of primary graft nonfunction.

[Metabolism in Arctium lappa L. at the primary stage of germination]

OBJECTIVE

To investigate the metabolic changes of the seeds at the primary stage of germination in Arctium lappa.

METHOD

By means of electrophoresis the changes of peroxidases and soluble proteins were assayed at the primary stage of germination.

RESULTS

The color of some original bands was enhanced, some original bands disappeared, and some new bands were detected in peroxidase patterns during the germinating process. The color changes were the main expression in soluble protein patterns. The bands of soluble proteins changed most obviously at 96 h and 120 h after germination.

CONCLUSION

It follows that the metabolic process in the seeds of Arctium lappa at the stage of germination is complex and 96 h and 120 h after germination are the key times of metabolism.

A neurotensin receptor antagonist inhibits acute immobilization stress-induced cardiac mast cell degranulation, a corticotropin-releasing hormone-dependent process

Stress worsens certain disorders such as migraines or asthma, and has also been implicated in sudden myocardial arrest. It was previously shown that acute psychological stress by immobilization results in dura mast cell degranulation, an effect blocked by pretreatment with antiserum against corticotropin-releasing hormone (CRH). Moreover, CRH was recently shown to induce skin mast cell degranulation. The effect of psychological stress was investigated on rat cardiac mast cells, because their release of coronary constrictive and proinflammatory molecules contributes to myocardial ischemia and possibly arrhythmias. Immobilization of rats for 30 min induced maximal cardiac mast cell degranulation as evidenced by light and electron microscopy. This effect was inhibited by pretreatment with the "antiallergic" drug sodium cromoglycate (cromolyn), which is thought to act primarily through mast cell stabilization. Mast cell degranulation was also blocked by preincubation with antiserum against CRH and was partially inhibited by a CRH type-1 receptor selective antagonist. Sensory neuropeptides did not appear to influence this effect, but a nonpeptide neurotensin receptor antagonist blocked stress-induced cardiac mast cell degranulation. This finding supports the involvement of neuropeptide neurotensin which is present in the heart and is known to trigger mast cell degranulation. These results indicate acute stress could result in local CRH and nonpeptide neurotensin release which could contribute to myocardial pathophysiology through direct or indirect release of cardiac mast cell mediators.

[The envelope formation of AcMNPV and the location of envelope protein gp64 in host cell]

Electron Microscopic study on the recombinant AcMNPV infected Sf9 cell showed that the virus has at least two forms of envelope formation: one is budding from plasma membrane and the other is enveloping in the nucleus by membrane structure. An additional possible pathway is budding from nuclear membrane. The envelope formation of AcMNPV in Sf9 cell line and its relationship with the envelope protein gp64 were investigated by using immunofluorescence techniques. The results showed gp64 was mainly located on the plasma membrane and nuclear membrane of infected cell. Whereas, there is no gp64 on the envelope of OV virus particles in the nuclei. This pattern cause the differences in envelope composition between the virus particles that budding from plasma membrane and nuclear membrane and those that enveloping in the nucleus.

Estrogen response elements can mediate agonist activity of anti-estrogens in human endometrial Ishikawa cells

Anti-estrogens like hydroxytamoxifen (OHT) have mixed agonist/antagonist activities, leading to tissue-specific stimulation of cellular proliferation. Partial agonist activity of OHT can be observed in vitro in endometrial carcinoma cells like Ishikawa. Here, we have compared several anti-estrogens (including extensively characterized OHT and pure anti-estrogens such as ICI164, 384 and RU58,668, which are devoid of uterotrophic activity) for their capacity to stimulate promoters containing estrogen response elements (EREs) or AP1-binding sites (12-O-tetradecanoylphorbol-13-acetate response elements, TREs), the two types of DNA motifs known to mediate transcriptional stimulation by estrogen receptors. Assays were performed in Ishikawa cells either by transient transfection or by using cell lines with stably propagated reporter vectors. In transient transfection experiments, none of the anti-estrogens displayed agonist activity on the promoters tested. In contrast, significant transcriptional stimulation was observed with low concentrations of OHT and RU39,411 in Ishikawa cells stably propagating reporter constructs containing a minimal ERE3-TATA promoter. In addition, micromolar concentrations of OHT, but not of RU39,411, stimulated stably propagated AP1-responsive reporter constructs. No transcriptional stimulation of ERE- or TRE-containing promoters was observed with the pure anti-estrogens ICI164,384 and RU58,668. These results indicate that the presence of estrogen response elements in promoters is sufficient to mediate cell-specific agonism of anti-estrogens at the transcriptional level, and that stimulation of AP1 activity may be restricted to a subset of anti-estrogens possessing agonist activity on EREs. In addition, our results suggest that transient transfections do not fully recapitulate in vivo conditions required to observe agonist activity of anti-estrogens.

[Surgical treatment of tuberculous tracheobronchial stenosis]

OBJECTIVE

To report the experience of surgical treatment of tuberculous tracheobronchial stenosis.

METHOD

Two trachial stenosis and 33 bronchial stenosis cases were analyzed. The modes of surgical treatment included: pneumonectomy in 14 cases, lobectomy in 13, lobectomy combined with bronchoplasty in 3, right pneumonectomy and partial trachial resection in 2, right main bronchus sleeve resection in 1, endotrachial granuloma resection in 1, right pneumonectomy and partial trachial resection combined with trachial reconstruction in 1.

RESULT

There was no bronchopleural fistula, tracheobronchial restenosis and death due to operation.

CONCLUSION

The first choice for the treatment of tuberculous tracheal or bronchial stenosis is lobectomy or pneumonectomy with trachial or bronchial plasty surgery.

Production of otoconia in the endolymphatic sac in the Japanese red-bellied newt, Cynops pyrrhogaster: light and transmission electron microscopic study

The formation of otoconia in the endolymphatic sac (ES) of the larval newt, Cynops pyrrhogaster, has been studied by light and transmission electron microscopy. Some of the epithelial cells of the ES contain an abundance of swollen vesicles, Golgi complexes, rough endoplasmic reticula and ribosomes at the late larval stages 50 and 51, approximately 26-30 days after eggs are laid. Five days later, at stage 52, crystals are present in the vacuoles between the epithelial cells. Serial sections indicate that these vacuoles actually form small canals which lie in the wall and join the lumen of the ES. Reconstruction of the ES shows that several canals are contained in the ES wall. At stage 56, about 72 days after eggs are laid, a large number of otoconia are present in the ES lumen, while the otoconia disappear from the canals. It appears that the otoconia are first produced in the canals and then released to the lumen. Some epithelial cells of the ES are thought to expel the organic and inorganic material to the canals to form the otoconia in situ. The process of formation of the otoconia in the ES is discussed.

Bcl-2 and Bax expression in adult rat hearts after coronary occlusion: age-associated differences

It has been reported that programmed cell death (apoptosis) occurs during myocardial infarction. The influence of age on programmed cell death or DNA fragmentation after coronary occlusion has not been extensively characterized. To test the hypothesis that there are age-related differences in susceptibility to DNA fragmentation during ischemia-infarction, we studied DNA fragmentation in young adult and old male F344 rat hearts after acute coronary artery occlusion. Hearts were studied at 1, 3, and 5 h and 1 and 7 days after coronary ligation. The percentage of apoptotic cells was determined by the in situ end-labeling technique, and internucleosomal fragmentation (DNA laddering) pattern was also analyzed. Our results show that 1) DNA fragmentation began earlier and peaked earlier in the old compared with young adult hearts during infarction; 2) there was heightened expression of both Bcl-2 and Bax in the old hearts at baseline; and 3) the Bcl-2-to-Bax ratio was higher in the older heart after coronary ligation. These results suggest that, compared with the young adult heart, the aged heart may be more susceptible to ischemia-induced DNA fragmentation.

A new and simple technique of total hepatic ischemia in the mouse

BACKGROUND

A model of total hepatic ischemia is currently not available in mice. Models described in rats using portosystemic shunts to achieve total ischemia have been notoriously difficult. In mice, the problem is compounded further when using this type of technique because of the small size of the animal. A new technique is described combining partial hepatectomy with clamping of the remnant liver.

METHODS

A partial (30%) hepatectomy is performed with resection of the caudate, right lateral, and quadrate lobes, and papillary process. Vascular microclamps are placed across the pedicles of the median and left lateral lobe at the level of the hilum to achieve total ischemia. Spontaneous portocaval shunts through caudate branches and collateral vessels prevent mesenteric congestion. Animals were studied for survival.

RESULTS

The procedure consistently took less than 30 min (25+/-2 min), and no bleeding of the resected tissue was observed. Evidence for total hepatic ischemia and spontaneous shunts was demonstrated by the use of an intraportal dye. All animals survived 60 min of ischemia, whereas all died after 90 min of ischemia.

CONCLUSION

This is a technically simple and rapid procedure to perform. In the current environment of multiple knockout mice and bioreagents that are available, a model of this type is essential.

Apoptosis of sinusoidal endothelial cells is a critical mechanism of preservation injury in rat liver transplantation

In livers excised for transplantation, sinusoidal endothelium appears especially vulnerable to injury during organ preservation in the cold and subsequent reperfusion. The degree of endothelial cell injury correlates with functional impairment of the graft following transplantation. The mechanism of injury remains obscure, but endothelial cell damage has been described as coagulative necrosis secondary to irreversible physico-chemical damage. We investigated whether endothelial cell death is caused by apoptosis rather than by necrosis. Tissue from rat livers stored for varying periods in cold (1 degree C) Euro-Collins solution and then reperfused for 1 hour at 37 degrees C were studied for evidence of apoptosis by detection of DNA fragmentation using the in situ terminal deoxynucleotidyl transferase d-uridine triphosphate nick end labeling (TUNEL) assay, DNA gel electrophoresis, and by transmission electron microscopy (EM). DNA fragmentation of the type characteristic of apoptosis was identified in 49.7% +/- 2.2% of sinusoidal lining cells after 8 hours of ischemia + reperfusion (viable graft) vs. 70.7% +/- 4.3% after 16 hours + reperfusion (nonviable graft) (P < .001). No such fragmentation was observed after cold preservation without reperfusion or in unpreserved, reperfused livers. EM demonstrated changes characteristic of apoptosis exclusively in endothelial cells. The study suggests that the apoptosis of sinusoidal endothelial cells is a pivotal mechanism of preservation injury in liver transplantation.

[HA-coated titanium implants used as orthodontic anchorage. An experimental investigation of implant stability and peri-implant neck tissue in dogs]

This study was aimed at the feasibility of using HA-coated titanium endosseous implants as orthodontic anchorage. These implants installed in dog's mandibles were loaded with the orthodontic force of 150 g for 3 months. The stability of the implant and the peri-implant neck tissue were investigated with radiograph and index evaluation. The findings demonstrated that no implant was mobile or loose or dislocated. The soft tissue around the cervical part of the implants had a slight inflammation because of bad oral hygiene and the stimulation of residual food attached to the stainless string. However, no resorption of marginal alveolor bone was found under sustained orthodontic force. The above results suggest that the HA-coated titianium implant can be used as anchorage for short-term orthodontic treatment.

[The effect of certain pro-inflammatory mediators on the pathogenesis of acute gastric mucosal lesion in early burn stage]

OBJECTIVE

To appraise the effect of certain pro-inflammatory mediators on the pathogenesis of acute gastric mucosal lesion in early burn stage.

METHODS

21 patients with burn injuries of over 30% TBSA were divided into A and B groups according to the main clinical indexes during shock resuscitation and hemodynamic parameters. Fiberoptic endoscopic examination, determination of intramucosal pH (pHi) and measurement of some mediators were done immediately after admission to the hospital and 4 and 7 days after burn injury.

RESULTS

It was demonstrated that the level of LPS in plasma, the content of TNF-alpha, IL-8 and ET in group B at 4 and 7 days postburn were significantly higher than those of group A, while the value of pHi in group B was markedly lower than that of group A. Damaging index of gastric mucosa was negatively correlated with pHi (r = -0.89, P < 0.05), but positively with ET (r = 0.91, P = 0.05).

CONCLUSIONS

These findings suggest that the inflammatory mediators and cytokines promoted secondary damage to gastric mucosa during early postburn. It was believed that pHi was a sensitive index, and it played an important role in the development of stress ulceration.

Development of the endolymphatic sac and duct in the Japanese red-bellied newt, Cynops pyrrhogaster

The development and maturation of the endolymphatic sac (ES) and duct (ED) were studied in the newt Cynops pyrrhogaster. The ES first appears as an oval capsule at the dorsal-medial tip of the otic vesicle at stage 39, about 11 days after oviposition. The ES consists of polymorphous epithelial cells with a minimum of cytoplasm. The intercellular space (IS) between the epithelial cells is narrow and has a smooth surface. At stage 44, the size of the ES increases as many vacuoles in the IS become filled. At stage 46, 18 days after oviposition, the ES elongates markedly and a slit-like lumen is found in the ES. The epithelium contains a few cell organelles which are scattered in the cytoplasm. The vacuoles in the IS are fused, which expands the IS. Two days later (stage 48), floccular material (endolymph) is present in the expanded lumen. The IS dilates and has a wide and irregular appearance. At stage 50, approximately 26 days after oviposition, the ES extends and expands significantly and crystals (otoconia) can now be seen in the widened lumen of the ES. The cytoplasm of the cuboidal epithelial cells contains an abundance of vesicles surrounded by ribosomes and Golgi complexes. Intercellular digitations are formed in the expanded IS. At stage 54, the ES forms a large bellow-like pouch. Numerous otoconia accumulate in the lumen. Free floating cells and cell debris can be seen in the lumen at this stage. The epithelial cells contain numerous cytoplasmic organelles which are evenly distributed in the cytoplasm. Granules are found in the apical and lateral cytoplasm. The IS is loose and displays a labyrinthine appearance. The primitive ED first appears as a connection between the ES and the saccule but no lumen is present inside at stage 39. At stage 46, a narrow lumen is formed in the ED, which corresponds to the formation of the ES lumen. At stage 50, as the ED extends, floccular material is seen in the lumen. At stage 54, the ED bears numerous microvilli on its luminal surface. Otoconia and endolymph are present in the ED. Tight junctions between the epithelial cells are formed at stage 46. A fully developed intercellular junctional complex is produced at stage 54. Based on the development of the ES and ED, the maturation of function of the ES and ED are discussed.