• Korean Journal of Veterinary Research
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• v.32 no.3
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• pp.321-331
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• 1992

The regional distribution and relative frequency of gastrointestinal endocrine cells were studied immunohistochemically in the gastrointestinal mucosa and pancreas of the fresh water turtle. Ten kinds of endocrine cells were identified in the gastrointestinal tract. Cholecystokinin-8-, bovine pancreatic polypetide-and glucagon-immunoreactive cells were seen throughout the gastrointestinal tract, also among them cholecystokinin-8-immunoreactive cells were most predominant in segment III. Although gastrin- and gastrin/cholecystokinin-immunoreactive cells were found from segment III to VI and X, respectively, they were numerous in segment III. Somatostatin-immunoreactive cells were observed from segment I to VII. 5-hydroxytryptamine- immunoreactive cells were detected in segment I, III, VIII, IX and X. Human pancreatic polypeptide-immunoreactive cells were demonstrated in segment V, VI, VIII, IX and X. Insulin-immunoreactive cells were found from segment III to X except for segment VIII, but rare in segment VII. Neurotensin-immunoreactive cells were found to be restricted to segment VIII, IX and X. No porcine chromogranin-, substance P- and bombesin-immunoreactive cells were detected throughout the gastrointestinal tract of the fresh water turtle. Although typical mammalian pancreatic islets encapsulated by connective tissue were not present in this species, five kinds of endocrine cells-glucagon, insulin, somatostatin, bovine pancreatic polypeptide and 5-hydroxytryptamine-were found in forming small or large groups and scattered in the exocrine gland region. However porcine chromogranin- and motilin-immunoreactive cells could not be demonstrated in the pancreas.

• The Korean Journal of Physiology
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• v.21 no.2
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• pp.201-210
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• 1987

수온변화에 따른 심맥관계 및 신장기능의 변화와 생체실험을 통한 온도에 의한 adrenoceptor의 변형을 알아보기 위해, 무마취 자라에서 $18^{\circ}C$에서 $25^{\circ}C$로 수온을 증가시 나타나는 혈압, 심박동수 및 신장기능의 변화를 관찰하고, epinephrine 1 ug/kg과 10 ug/kg을 상이한 온도에 노출된 자라의 정맥내 투여하여 나타나는 효과를 비교하였다. 1) $18^{\circ}C$에서 $25^{\circ}C$로 수온을 증가시킴에 따라 심박동수는 현저히 증가하여 일정하게 유지되었으나, 혈압 및 혈장 renin 활성도는 변화하지 않았다. 온도증가에 의해 뇨량, 사구체여과율 및 전해질 배설량의 현저한 증가를 보였으나 90분부터는 서서히 감소하기 시작하였다. 2) 수온 $18^{\circ}C$에 노출된 자라에서 epinephrine은 dose-dependent한 양상으로 혈압 및 심박동수를 증가시켰으며, 다량의 epinephrine 투여시 작용시간은 현저히 연장되어 있었다. $25^{\circ}C$에 노출된 자라에서는 epinephrine에 의한 혈압상승 효과 및 심박동수 증가는 나타났으나, dose dependency나 작용시간의 차이는 발견할 수 없었다. 3) 동량의 epinephrine에 의한 혈압 및 심박동수의 증가효과는 $18^{\circ}C$와 $25^{\circ}C$에 노출된 자라에서 유의한 차이를 발견할 수 없었으나, $18^{\circ}C$에 노출된 자라에서 epinephrine의 작용시간 및 반감기가 현저히 연장되어 있었다. 4) Epinephrine 투여에 의해 뇨량, 사구체여과율 및 전해질 배설량의 증가를 관찰하였으며, 이는 dose-dependent 양상이었다. 그러나, 신장효과의 유의한 차이는 상이한 온도에 노출된 두 군에서 발견할 수 없었다. 이상의 결과로, 온도증가에 의한 이뇨 및 sodium 배설효과는 혈관이완에 의한 사구체여과율의 증가에 기인한 것으로 사료되며, 상이한 온도에 노출된 자라에서 epinephrine 효과의 차이를 발견할 수 없었던 것은 본 실험에서 가한 좁은 범위의 온도의 변화 내에서는 adrenoceptor의 변형이 나타나지 않을 것이라고 추론하였다. 그러나 저온에서의 epinephrine의 작용시간의 연장은 아마도 epinephrine의 파괴 효소의 활성도의 감소인 것으로 사료된다.

• Applied Microscopy
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• v.25 no.2
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• pp.39-52
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• 1995

Pinealocytes in the lower vertebrate are known to have photoreceptive function. These photoreceptor cells have been characterized morphologically in various species of lower vertebrates. No such ultrastructural studies, however, were reported in fresh water turtle. The purpose of this study is to characterize the pinealocytes and the phylogenetic evoluton of these cells is discussed in terms of functional analogy. I. Light microscopy: The pineal body was divided into incomplete lobules by connective tissue septa containing blood vessels, and parenchymal cells were arranged as irregular cords or follicular pattern. In the lobules, glandular lumina were present and contained often densely stained materials. II. Electron microscopy: The pineal parenchyma had three categories of cells: photoreceptor cells, supportive cells and nerve cells. The photoreceptor cells had darker cytoplasm compared to the supportive cells, and the enlarged apical cytoplasm(inner segment) containing abundant mitochondria and dense cored vescles protruded into the glandular lumen in which lamellar membrane stacks(outer segment), dense membranous materials, and cilia were present. Some of these lamellated membrane stacks appeared to be dege-nerating while others were apparently newly formed. Constricted neck portion of the photoreceptor cells contained longitudinally arranged abundant microtubules. centrioles and cross-striated rootlets. Cell body had well developed Golgi apparatus, abundant mitochondria, dense granules($0.5{\sim}1{\mu}m$), dense cored vesicles($70{\sim}100nm$), and rough endoplasmic reticulum occasionally with dense material within its cisterna. Basal portion of the photoreceptor cells had basal processes often with synaptic ribbons, which terminate in the complicated zone of cellular and neuronal processes. Synatpic ribbons often made contact with the nerve processes and the cell processes of neighboring cells. In some instances, these ribbons were noted free within the basal process and were also present at the basal cell mem-brane facing the basal lamina. Obvious nerve endings with clear and dense cored vesicles were observed among the parenchymal cells. Photoreceptor cells of the snapping turtle pineal body were generally similar in fine structure to those of other lower verterbrates reported previously, and suggested to have both photoreceptive and secretory functions which were modulated by pinealofugal and pinealopedal nerves. The supportive cells were characterized by having large dense granules($0.3{\sim}1{\mu}m$), abundant ribosomes, well developed Golgi apparatus and rough endoplasmic reticulum. These cells were furnished with microvilli on the luminal cell surfaces, and often had centrioles, striated rootlets, abundant filaments especially around the nucleus, and scattered microtubules. Some supportive cells had cell body close to the lumen and extended a long process reaching to basal lamina, which appeared to be a glial cell. Nerve cells within the parenchyma were difficult to identify, but some large cells located basally were suspected to be nerve cells, since they had synaptic ribbon contact with photoreceptor cells.