• The Korean Journal of Zoology
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• v.35 no.1
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• pp.8-16
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• 1992

포유류의 심방에 주로 존재하여 체액 및 전해질 대사의 조절과 혈압 조절에 관여하는 atrial natriuretic peptide(ANP)가 담수어류인 미꾸라지(Misgumus mizolepis G.)의 심장 및 기타조직에도 존재하는지 알아보고 이들의 분자적 특성 및 온도차에 의한 함량변동을 조사하였다. 미꾸라지의 심장과 동맥구의 추출액은 모두 희석농도에 따라 표준곡선에 평행하는 ANP immunoreactivity를 나타냈다. 미꾸라지의 심장과 동맥구 모두에서 저분자량 및 고분자량의 immunoreactive ANP(irANP)가 관찰되었다. 한편 미꾸라지의 심장내 irANP함량은 61.56 $\pm$ 5.08 pg/mg이었으며, 심장외 조직인 동맥구는 60.59 $\pm$ 5.04 pg/mg으로 거의 동량의 irANP를 함유하였다. 미꾸라지를 저온상태에 적응시킨 경우에는 심장보다도 동맥구에서 더 유의한 irANP의 함량변동을 보였다(p < 0.01), 미꾸라지의 심장 및 동맥구에 존재하는 irANP는 주로 고분자량의 Pro-ANP가 관찰되므로써 미꾸라지의 심장과 동맥구 모두가 irANP를 조직내에서 합성할 것임을 시사하였다. 아울러 온도는 미꾸라지의 경우에서 irANP의 함량변동에 영향을 주는 요인임을 알 수 있었다.

• The Korean Journal of Zoology
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• v.36 no.1
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• pp.97-108
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• 1993

The biochemical characteristics of immunorecative atrial natriuretic peptide (irAUPP and the changes in the levels of irANP in the heart were investigated during the metamorphosis of frog tadpoles. Immunohistochemical localization of pro-ANP in cardiocfes and the presence of irAW in the peritoneal fluid of metamorphosing tadpoles were also examined. The major form of irANP in the cardiocvtes of tadpoles (Rana omurensisp was high molecular weight on gel filtration chromatographv and reverse-phase HPLC. The levels of irANP in the atrium of tadpoles were five to seven times higher than those in the ventricle. In metamorphosing tadpoles the levels of irANP in the atrium increased at stage XX, the climax of metamorphosis, and decreased at stage XXV (P < 0.051, the completion of metamorphosis. When the levels of irANP was expressed as a function of body weight of tadpoles, a continuous increase in the levels of irANP was observed from pre- to postmetamorphosis (P < 0.051. The levels of irAUP in the ventricle were found to be higher in the adult frogs than in tadpoles (R. omurensisl (P < 0.01). Pro-ANP (31-67) immunoreactivity was detected in the ventricle as well as in the atrium of tadpoles fR. nigromaculotal. The peritoneal fluid was also found to contain low molecular weight of irAUP and the levmils of irANP were 55.4 $\pm$ 9.1 pg/ml. Changes of the level of irANP at different stases of the life cycle suggest that ANP may play a role in the regulation of body fluid homeostasis of frog tadpoles during the metamorphosis.

• The Korean Journal of Zoology
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• v.35 no.3
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• pp.263-270
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• 1992

Responses of immunoreactive atrial natriuretic peptide (ir-ANP) to environmental temperature were studied in the freshwater catfish, Silums usotus, acclimated at various temperatures for one week. According to increase in environmental temperature, plasma sodium and chloride concentrations, and osmolality were significantly increased, while hematocrit showed a marked decrease. When the catfishes frere acclimated at cold $(3^{\circ}C)$ or warm $(18^{\circ}C)$ temperatures, ir-ANP contents in the atrium and bulbus arteriosus were significantly lower than those at $9^{\circ}C.$ However, ventricular contents of ir-ANP urere not different among the three groups.Levels of plasma ir-ANP in the catfish increased in response to the increment of acclimated temperature. On the basis of these results, we suggest that the environmental temperature may modulate synthesis and secretion of ir-hUP in the fish. We also suggest that changes of plasma ir-ANP levels may be associated with the control of body fluid homeostasis.