• Applied Microscopy
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• 제27권4호
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• pp.357-372
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• 1997

To study the age-related morphological differences of the retinal pigment cells and Bruch's membrane of mouse, retinae of one week-old, five weeks-old, eight weeks-old, six months-old, twelve months-old, eighteen months-old, twenty-four months-old and thirty months-old ICR mice were dissected out under anesthesia. Pieces of the tissue taken from the posterior region of the retina were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde (0.1 M Millonig's phosphate buffer, pH 7.3), and 1% osmium tetroxide (0.1 M Millonig's phosphate buffer, pH 7.3), and embedded in araldite mixture. The ultrathin sections were stained with uranyl acetate and lead citrate, and were observed under a JEM 100 CX-II electron microscope. Observed results were as follows: 1. Retinae of one week old mouse exhibit that some parts of the pigment cell provided with basal foldings, whereas other parts of the one contain without basal foldings. After (ive weeks-old, all retinal pigment cells have the basal infoldings. 2. In the one week-old, stage 1 and stage 2 melanosomes were observed in the retinal pigments cells, but after five weeks-old, most of the retinal pigment cells contain some matured stage melanosomes (stage III and stage IV). 3. The phagosomes in the retinal pigment cells were increased during aging. 4. After eighteen months-old, electron dense materials are observed within the basal infoldings. 5. After eighteen months-old, the thickness of the Bruch's membrane is prominently increased. The thickness of the basal laminae of the pigment cell and the choriocapillary endothelium is more prominently increased as compared with that of the other components of the Bruch's membrane. 6. The thickness of the basal lamina of the pigment cell is more prominently increased as compared with that of the choriocapillary endothelium on aging. From the above results, it was suggested that the pigment cell and Bruch's membrane matures structurally In five weeks, and the function of the pigment cell is prominently suppressed around eighteen months-old, and thereafter the functional suppression is continued on aging.

• Applied Microscopy
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• 제27권1호
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• pp.13-30
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• 1997

The experiment was performed to study the morphological responses of the thymus of the mice, to antitumour agents (5-Fluorouracil or mitomycin C). Healthy adult mice weighing 25 gm each were divided into normal and experimental groups. 5-Fluorouracil (60 mg/kg) or Mitomycin-C $(400{\mu}g/kg)$ were injected subcutaneously to the animals every other day. Animals were sacrificed at 4 days and 7 days following the first injection. Pieces of the tissue taken from the thymus were prefixed with 2.5% paraformaldehyde-l.5% glutaraldehyde, followed by post-fixation with 1% osmium tetroxide. Ultrathin sections stained with uranyl acetate and lead citrate were observed with a JEM 100 CX-II electron microscope. The observed results were as follow: 1. Apoptoses of T-lymphocytes were observed more frequently in the thymus of the experimental groups than in those of a normal group. 2. In the experimental group, the plasma cells with distended cisternae of the granular endoplasmic reticulum and the eosinophile leukocytes were observed frequently. 3. In the experimental group, newly forming Hassall's corpurscles were observed frequently. 4. In the mitomycin-treated group, the epithelial reticular cells containing distended perinuclear cisternae, distended the granular endoplasmic reticula and pyknotic nuclei were observed in the cortico-medullary junctional area. 5. In the mitomycin-treated group, nuclear bodies with medium electron dense materials were often observed in the T lymphocyte. 6. In the 5-fluorouracil-treated groups, fused and dissolved tonofilament bundles and apoptotic bodies were observed in the some epithelial reticular cells in the medullary area. 7. In the 5-fluorouracil-treated groups, some elongated and bar-shaped lysosomes with electron lucent gap were often observed in the macrophages. 8. In the 5-fluorouracil-treated group, membrane complex of the smooth endoplasmic reticulum were ofen observed in the macrophage. From the above results, it was suggested that 5-fluorouracil or mitomycin could induce rapid involution of the thymus, and disturb maturation and differentiation of T lymphocytes, and, in turn, supress immunity.

• Applied Microscopy
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• 제27권4호
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• pp.373-389
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• 1997

Morphological difference of the renal glomerulus at different age groups have been studies in one week-old, five weeks-old, eight weeks-old, six months-old, twelve months-old, eighteen months-old, twenty-four months-old, and thirty months-old ICR mice. Pieces of the tissue taken from the renal corticies were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde solution (0.1 Millonig's phosphate buffer pH 7.3), and 1% osmium tetroxide solution (0.1 M Millonig's phosphate buffer, pH 7.3), and were embedded in araldite mixture. The ultrathin sections were stained with uranyl acetate and lead citrate solution, and were observed under a JEM 100CX-II electron microscope. The results were as follows: 1 In the one week-old mouse, thicknesses of the three layers of the glomeluar basal lamina (lamina densa, lamina rara interna and lamina rara externa) are similar, but in the five weeks-old mouse, thick lamina densa becomes a greater portion of the thickness of whole glomerular basal lamina. 2. No difference was noticed between thickness of the renal glomerular basal lamina of the five weeks-old mouse compare with that of the one week-old one, but basal lamina of the eight weeks-old one is thickened considerably and thicknesses were maintained through twelve months-old one. After eighteen months, the thickness of the glomerular basal lamina is increased remarkably. 3. After eighteen months, electron dense deposits within the basal lamina of the renal glomeruli are observed frequently. 4. Amount of the microfilaments in the mesangial cells and the mesangial matrices are increasing during aging. 5. The thicknesses of the basal laminae of the Bowman's capsule are increasing during aging. 6. After twenty four months, the proximal tubular cell-like parietal cells with well developed microvilli are observed frequently. From the above results, it was suggested that the renal glomerulus matures structurally in five weeks, and the function of the glomerulus is suppressed after eighteen months.

• Applied Microscopy
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• 제22권2호
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• pp.1-14
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• 1992

This experiment was performed to study the morphological responses of the parafollicular cells of rat following X-ray irradiation. Male rats were divided into normal and experimental groups. The head and neck region of the rat, under sodium thiopental anesthesia, was exposed to 3,000 rads or 6,000 rads of radiation in a single dose, respectively. The source was a Mitsubishi Linear Accelerator ML-4MV. The target to skin distance was 80 cm, and the dose rate was 200 rads/min. The rate of experimental groups were sacrificed on the 6th hour, 2nd and 6th day after X-ray irradiation. Pieces of the tissue taken from the thyroid gland were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde (0.1M Millonig's phosphate buffer, pH 7.3), and in 1% osmium tetroxide (0.1M Millonig's phosphate buffer, pH 7.3), and embedded in araldite mixture. The ultrathin sections stained with uranyl acetate and lead citrate were observed with JEM 100 CX-II electron microscope. The results were as follow; 1. Two types of the parafollicular cells, according to their electron densities, were found, i. e., light cells and dark cells. 2. Three types of the parafollicular cells, according to their sizes of secretory granules were found, i.e., small granule cells ($85nm{\pm}20.1;64{\sim}102nm$), medium granule cells ($120nm{\pm}26.5;77{\sim}179nm$), and large granule cells ($165nm{\pm}25.7;128{\sim}189nm$). 3. The differential ultrastructural changes of the cells according to their cell types, i.e., dark and light cell, or small, medium and large granule cells, were hardly observed in the time and dose range covered by this study. 4. The morphological changes of the parafollicular cells were not pronounced after exposure to 3,000 rads of X-ray. 5. Swollen cisternae of the granular endoplasmic reticulum and partial cytolysis were observed after exposure to 6,000 rads of X-ray. 6. Above results suggest that the parafollicular cells showed the alterations of mitochondrial and granular endoplasmic reticular swelling, and partial cytolysis, but only in doses of 6,000 rads.

• Applied Microscopy
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• 제22권2호
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• pp.15-29
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• 1992

The gallbladder is known to have the function of the storage and the concentration of the bile produced by the liver. This function is carried out by the removal of water and inorganic electrolytes. Extrahepatic cholestasis or the impairment of excretion of the bile leads to the distension and loss of the function of the gallbladder. The purpose of this study was to examine the ultrastructural characteristics of the normal gallbladder epithelial cells, and their structural changes induced by the ligation of common bile duct of the rabbit. Common bile duct ligation was performed under ether anesthesia. The rabbits were sacrificed on the 1st, 3rd, 5th, 7th and 14th day, respectively after operations. The tissue blocks of the gallbladder were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde prior to fixation in 1% osmium tetroxide, and embedded in the araldite mixture, and observed with JEM 100 CX-II electron microscope. The results were as follows: 1. The normal gallbladder epithelium of adult rabbit demonstrated two cell types, the ordinary epthelial cell and the dark cell. The dark cells have electron dense cytoplasm, and were found much infrequently, whereas ordinary epthelial cells were found quite numerous. 2. The ordinary epthelial cells of normal gallbladder were provided with the regular microvilli at the free surface and the images of pinocytotic activities in the apical cytoplasm, and exhibit highly convoluted lateral surfaces with elaborated microfolds. These figures of the cells suggest that they are resorptive in functional activity. 3. In the early stages (1st, 3rd, 5th day groups) following the ligation, the apical cytoplasm of some cells is protruding from the free surface and lost their microvilli. Numerous mucous granules filled in the apical and supranuclear cytoplasm compactly. 4. In the late stages (7th, 14th day groups) following the ligation, many light cells containing mumerous mucous granules are seen, between the ordinary epthelial cells. Mucous granules are fused each other, and are discharged into the lumen from the apical cytoplasm. The lateral membranes are straight or undulating without any interdigitations. From the above results, it was concluded that in the cholestasis induced by the common bile duct ligation, there is a tendency for the mucosal epithelium of the rabbit gallbladder to have secretory rather than an absorptive function.

• 한국환경보건학회지
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• 제36권5호
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• pp.391-401
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• 2010

A reduction in risk of occupational exposure to chemical hazards within the workplace has been the focus of attention both through industry initiatives and legislation. The aims of this study were to develop an exposure matrix by industry and process, and to apply this matrix to control the risk of occupational exposure to Dichloromethane (DCM). The exposure matrix is a tool to convert information on industry and process into information on occupational risk. The exposure matrix comprised industries and processes involving DCM, based on an exposure database provided by KOSHA (the Korean Occupational Safety and Health Agency), which was gathered from a workplace hazards evaluation program in Korea. The risk assessment of the exposure matrix was performed using Hallmark risk assessment tool. The results of the risk assessment were indicated by a Danger Value (DV) calculated from the combination of hazard rating (HR), duration of use rating (DUR), and risk probability rating (RPR) of exposure to the chemical, and were divided into four control bands which were related to control measures. The applicability of the risk assessment of the exposure matrix was evaluated by a field study, and survey of the employees of the exposure matrix groups. Among 45 industries examined, this study found that greater attention should be paid to two industries: the manufacture of other optical instruments and photographic equipment, and the manufacture of printing ink, and to one process among 47 examined, the packing process in the manufacture of printing ink, because these were regarded as carrying the highest risk. This tool of a risk assessment for the exposure matrix can be applied as a general exposure information system for hazard control, risk quantification, setting the occupational exposure limit, and hazard surveillance. The exposure matrix includes workforce data, and it provides information on the numbers of exposed workers in Korea by agent, occupation, and level of exposure and risk.

• Applied Microscopy
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• 제23권2호
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• pp.11-26
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• 1993

This experiment was performed to study the morphological responses of the pigment epithelial cell and the Bruch's membrane of the retina of rat following X-ray irradiation. Male rats were divided into normal and experimental groups. The heads of the rats, under sodium thiopental anesthesia, were exposed to 3,000 rads or 6,000 rads of radiation in a single dose, respectively. The source was a Mitsubishi Linear Accelerator ML-4MV. The target to skin distance was 80cm, and the. dose rate was 200 rads/min. The experimental groups were sacrificed on the 6th hour, 2nd and 6th day after X-ray irradiation. Under anesthesia, 1% glutaraldehyde-1% paraformaldehyde solution(0.1M Millonig's phosphate buffer, pH 7.3) was perfused through the left ventricle and ascending aorta. Pieces of the tissue taken from the posterior region of the retina were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde(0.1M Millonig's phosphate buffer, pH 7.3) and 1% osmium tetroxide(0.1M Millonig's phosphate buffer, pH7.3), and embedded in araldite mixture. The ultrathin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100 CX-II electron microscope. The results were as follow; 1. The morphological changes of the pigment epithelial cells were not pronounced after exposure to 3,000 rads of X-ray. But on the 6th hour after exposure to 6,000 rads of X-ray, bulging nuclear membrane protruding into the cytoplasm and nuclear chromatin clumped into numerous masses along the nuclear membrane were observed. At the 2nd and 6th day post-irradiation, partial cytolysis or necrosis were seen. 2. The thickness of the Bruch's membrane of the experimental groups were increased in the time and dose range covered by this study, and splitting or diffusing basal laminae of the choriocapillary layer were observed frequently in the experimental group. Above results suggest that large amount(6,000 rads) of head irradiation induce direct hazardous effects on the pigment epitherial cells and Bruch's membrane of the retina of the rat, but pigment epithelial cells are more radioresistant than Bruch's membrane.

• Applied Microscopy
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• 제24권2호
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• pp.78-92
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• 1994

Lysozyme has been reported to be present in the secretory granules of the Paneth cell, and lysozyme immunoreactivity has been detected by immunogold method in Paneth cells of the intestine of human, mouse and rat. The present study was aimed at clarifying the intracellular distribution and changes of the lysozyme immunoreactivity in rabbit Paneth cell after common bile duct ligation of rabbit, using the electron microscope immunogold technique. Healthy adult rabbits weighing about 2kg body weight were divided into normal and bile duct ligated groups. Common bile duct ligation was performed aseptically under ether anesthesia. Experimental animals were sacrificed on the 1st, the 3rd, the 5th, the 7th and the 14th day after the operation. Mucosal specimens from the intestinal gland of ileum were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde, followed by 1% osmium tetroxide, embedded in araldite mixture, cut with LKB-V ultratome. Ultrathin sections were placed on parlodion coated nickel grids (200mesh). The section-bearing grids were floated upside down on the added substance in a moist chamber at room temperature except for the primary antibody step, which was at $4^{\circ}C$. Sections were etched with a saturated solution of sodium m-periodate for 60min. After etching, sections were pretreated with 0.02M tris buffered saline (TBS), pH 8.4, with 1% bovine serum albumin (BSA, Sigma) for 60min, then treated polyclonal rabbit anti-human lysozyme (Dakipatts) diluted 1 : 50 in TBS with 0.1% BSA for 20hr. Subsequently, grids were incubated 60min in biotinylated goat anti rabbit IgG (Amersham) diluted 1 : 100 in TBS with 0.1% BSA. After this, sections were incubated 60min on streptavidin gold G10 (Amersham) diluted 1 : 50 in TBS with 0.1% BSA. After each step, the grids were briefly rinsed with TBS with 0.1% BSA. After the strepavidin gold step, the sections were jet washed with distilled water. Counterstain of the sections performed by uranyl acetate and lead citrate, and observed with JEM 100 CX II electron microscope. Observed results were as follow; 1. Secretory granules of mouse Paneth cells have a lysozyme immunoreactivity and also eosinophil leucocyte of rabbit applied for the positive-control stain, are well labeld with gold particles. 2. Normal rabbit Paneth cells have a lysozyme immunoreactivity restricted on the secretory granules. 3. Amount lysosomes containing myelin figures in the Paneth cells were significantly increased from 5th day after the common bile duct ligation. 4. Immunoreactivity of Paneth cell secretory granules were more activated on the 3rd day after the common bile duct ligation as compared with those of the normal animal. But the lysozyme immunoreactivity were decreased from the 5th day after the common bile duct ligation. 5. Considering the above finding, lysozyme contained Paneth cell are affected following of common bile duct ligation, whereas lysosomes containing myelin-figure do not exhibit any immunoreactive relationship with those of secretory granules.

• Applied Microscopy
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• 제35권3호
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• pp.153-163
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• 2005

이 연구는 생쥐의 샅부위에 Ehrlich 암세포를 이식한 후 BCG (Bacillus Calmette-Guerin)를 투여하였을 때, 위점막 으뜸세포의 미세구조에 미치는 영향을 알아보기 위하여 시행하였다. 실험동물로는 체중 25 g 내외의 ICR생쥐를 사용하였으며 정상대조군과 실험군으로 구분하였다. 정상대조군 이외의 실험군 동물들은 샅부위 피부밑조직에 각각 $1x10^7$개의 Ehrlich암세포를 이식한 후, 다음날부터 BCG 투여군은 BCG를 피부밑조직에 격일 간격으로 7회 투여했으며, 종양대조군은 암세포이식 후에 약제 대신 0.2 mL의 생리식염수를 피부밑조직에 격일간격으로 7회 주사하였고, 정상대조군은 암세포를 이식하지 않은 동물을 사용하였다. 모든 실험군은 마지막 주사한 다음날 오전 10시에서 11시 사이에 ether마취하에 앞배벽을 열어 위조직을 절취하였다. 절취한 조직은 통상적인 방법으로 전자현미경관찰을 위한 표본을 작성한 후, JEM 100 CX-II 전자현미경으로 비교 관찰하였다. 각 세포는 5,300 배율로 촬영한 후 3배로 확대 인화한 사진을 비교 관찰하였으며, 각 실험군마다 200개 이상의 과립의 지름과 사립체의 크기(장경)를 측정하였으며 student-t test를 이용하여 통계처리 하였다. BCG 투여군의 으뜸세포는 과립세포질세망과 골지복합체의 수조가 다소 팽대되고 수초구조가 다소 많이 관찰되는 이외는 정상대조군에 비해 큰 차이가 없었다. 으뜸 세포의 분비과립의 크기는 정상대조군, 종양대조군 및 BCG 투여군의 경우 각각 $0.98({\pm}0.108){\mu}m,\;1.05({\pm}0.092){\mu}m$ 및 $0.93({\pm}0.053){\mu}m$ 였다. 으뜸세포의 사립체의 크기는 정상대조군, 종양대조군 및 BCG 투여군이 각각 $0.80({\pm}0.130){\mu}m,\;0.83({\pm}0.143){\mu}m$ 및 $0.72({\pm}0.078){\mu}m$ 였다. 이상의 결과를 종합해보면 BCG를 반복 투여하면 위점막으뜸세포의 분비과립이 약간 작아지는 등 분비기능이 다소 억제되나 그 정도가 경미하여 으뜸세포의 분비기능에 큰 손상을 주지 않는 것으로 생각된다.

• Applied Microscopy
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• 제35권3호
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• pp.135-152
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• 2005

중추신경계통에서도 최고중추인 이마앞겉질 (prefrontal cortex)은 거의 모든 대뇌겉질과 연결되어 있어서 대뇌겉질 각 부분에 저장된 감각, 운동, 언어... 등 모든 정보를 받을 뿐만 아니라, 앞뇌의 바닥핵들 (basal forebrain nuclei)을 비롯한 많은 신경핵들과도 연결되어 있어서 생체 내부환경과 본능에 관한 정보도 받아드린다. 이들 연결을 통해서 이마앞겉질은 변연계통의 본능, 감정, 기억, 학습기능과 줄무늬체계통의 적절한 표현, 대응, 절차기억, 운동조절기능들을 연계하고 조정한다. 앞뇌의 바닥핵들(꼬리핵 caudate nucleus, 줄무늬체바닥핵 fundus striati nucleus, 중격옆핵 accumbens septi nucleus, 중격핵 septal nucleus)도 역시 변연계통과 줄무늬체계통 사이에서 해부학적으로나 기능적으로도 교차기능이 있는 것으로 알려져 있다. 이 실험은 흰쥐의 이마앞겉질은 제거한 다음, 앞쪽 앞뇌의 바닥핵들에서 변성종말들이 있는지 여부와 그 미세구조를 관찰하려고 시행했다. $250{\sim}300g$된 흰쥐를 실험동물로 이용하였으며, 흰쥐들을 정상군, 대조군, 수술군으로 구분하였다. 수술군은 마취시킨 다음, 뇌수술장치에 고정시키고, 머리피부를 절개한 다음, 이마뼈에 구멍을 만들고, 이 구멍을 통해 이마앞겉질을 흡인하여 제거했다. 대조군은 이마뼈에 구멍을 만드는 과정까지만 실행하였고, 정상군은 아무조치도 취하지 않았다. 수술 후 2일 경과 후에 전자현미경 관찰을 위해 1% glutaraldehyde-1% paraldehyde 혼합액 (pH 7.4)에 1차 고정하였고, 뇌를 적출하여 고정액에 냉장시켰다가, 다음날 해당 신경핵을 적출하여 2차 고정액 (2% osmium tetroxide액)에 고정하였다. Araldite 혼합액에 포매하여 ultratome-V로 자른 절편은 4% uranyl acetate와 2.7% lead citrate로 염색하여 JEM 100CX-II 전자현미경으로 관찰하였다. 관찰결과 네 신경핵에서 모두 변성 축삭종말이 관찰되었는데, 출현비율은 상당한 차이를 보여서 가장 변성이 심한 신경핵은 꼬리핵 이었고, 다음은 줄무늬체바닥핵, 중격옆핵, 중격핵의 순서였다. 변성축삭종말이 각 부위에서 연접하는 모양을 비교한 결과 꼬리핵과 줄무늬체바닥핵에서는 모두 가지돌기가시(dendritic spine)에 연접하였으나, 중격옆핵과 중격핵에서는 가지돌기 (dendrite)에 연접하는 것과 가지돌기가시에 연접하는 것이 혼재하였다. 이들 두 신경핵 무리는 이마앞겉질에서 기원하는 축삭종말의 연접차이로 볼 때 서로 다른 회로계통에 속할 것으로 생각되며, 문헌고찰을 통해서 꼬리핵과 줄무늬체바닥핵은 줄무늬체회로 (striatal circuit)에 속하고 중격옆핵과 중격핵은 변연계통회로(limbic circuit)에 속할 것으로 판정했다. 이마앞겉질은 생리적, 약리적, 신경학적 및 형태학적 근거들로 보아 바닥핵들을 통해 변연계통과 대뇌겉질 전체에 영향을 미칠 것으로 여겨지는데, 본 실험에서는 네 종류의 바닥핵들, 즉 꼬리핵, 줄무늬체바닥핵, 중격옆핵 및 중격핵과 관련된 신경연접들을 관찰하였으며, 그 결과를 문헌 고찰한 결과 변연계통과 줄무늬체계통이 앞뇌의 바닥에 있는 신경핵들에서 형태학적 교차연결을 통해 정서와 마음의 상태를 행동과 대응으로 표현하는 중요한 신경회로가 존재함을 제안하였다.