고양이 적출 취장 외분비 기능에 대한 난소 홀몬의 영향

Abstract

[한글]

취외분비는 주로 신경성인자 및 위장홀몬에 의하여 조절되며, steroid홀몬도 취외분비기능 조절에 한 요인으로 관여한다고 알려져 있다. 체내 steroid홀몬은 부신과 난소에서 cholesterol로부터 합성되며 이들은 생체의 항상성 유지에 중요한 작용을 한다.

취외분비에 대한 부신피질홀몬의 영향에 관해서는 상반된 보고가 많으나, 대체로 glucocorticoid는 취외분비를 억압하며, mineralocorticoid는 취외분비를 항진시키는 것으로 받아들여지고 있다.

또한 취선포 세포질에 estrogen과 결합하는 단백이 있음이 알려져 있고 progesterone은 취종양 세포의 세포내 mRNA 및 amylase의 양을 증가시킨다고 하여 난소홀몬 역시 취외분비기능과 관련성이 있음이 시사되고 있다.

따라서 본 실험에서는 전해질 용액을 관류하는 생체외 적출 고양이 취장표본을 이용하여 취외분비기능에 대한 난소홀몬의 직접적인 영향을 검색하고자 하였다.

실험동물로는 1.5kg내외의 잡종고양이를 암수 구별없이 사용하였으며 secobarbital 마취하에 취장을 적출하여 Krebs Ringer bicarbonate buffer(KRBB)를 관류시켰다. 난소홀몬의 영향을 검색하기 위하여 estrogen 또는 progesterone을 각각 10**-8 ― 10**-6 M되게

KRBB에 첨가하여 30분간씩 관류하였다. 취액분비는 secretin의 submaximal dose 주입으로 일정하게 유지시켰고 취효소분비는 secretin 주입하에 cholecystokinin(CCK) 자극으로 유발시켰다.

실험성적을 요약하면 다음과 같다.

1. Estrogen관류로 적출취장의 외분비기능은 항진되었으며 estrogen 10**-8 M이상의 농도에서 secretin에 의한 취액분비와 CCK자극에 의한 amylase분비가 증가되었다.

2. Progesterone관류로 취외분비는 증가하여 secretin자극에 의한 취액분비는 10**-6 M관류시 증가하였고, amylase분비는 CCK자극에 의한 progesterone 10**-7 M첨가로 증가하였다.

3. Estrogen 10**-7 M 존재하에 progesterone을 관류함으로써 amylase 분비 변동은 관찰되지 않았으며, secretin자극에 의한 취액유출은 변동이 없었다.

이상의 결과로 미루어 보아 estrogen 및 progesterone등 난소 홀몬은 취선포에 직접 작용하여, 취액 및 취효소분비를 항진시키며 취외분비에 대한 progesterone의 효과는 estrogen과 상관없이 나타난다고 생각한다.

Influence of Ovarian Hormones on the Exocrine Secretion in Isolated Cat Pancreas

Jae Won choi

Department of Medical Science, The Graduate School, Yonsei University

(Directed by Professor Kyung Hwan Kim)

Regulation of pancreatic exocrine secretion is comprised of a complex interplay

between hormonal and nervous systems. It has been claimed that steroid hormones may

participate in maintaining the exocrine function of the pancreas. Corticosteroids

and ovarian hormones are synthesized from the same precursor, cholesterol, in vivo

and they are important regulators of homeostasis.

Though the effects of corticosteroids on pancreatic function are not consistant,

it is widely accepted that the glucocorticoid inhibits the secretory function

whereas mineralocorticoid stimulates.

Several studies have suggested that ovarian hormones exert significant influence

on the exocrine pancreas. And pancreatic function of exocrine cells may be

regulated by estrogen and estrogen-binding protein. Also, it was reported that

protesterone increased both the cellular content of amylase and cytoplasmic mRNA of

rat tumor cell line AR 42J.

In the present study, attempt was made to examine the direct effects of estrogen

and progesterone on exocrine function employing saline perfused isolated cat

pancreas.

Mongrel cats, of both sexes weighing about 1.5Kg , were anesthetized with

secobarbital (30mg/kg, ip), then the pancreas was isolated and perfused with Krebs

Ringer bicarbonate buffer(KRBB) gassed with 95% 0^^2-5% CO^^2 at the rate of 6

ml/min. Ovarian hormone, estrogen or progesterone was added to the perfusate for 30

minutes. Submaximal dose of secretin was infused to maintain pancreatic flow and

cholecystokinin was injected to evoke the enzyme secretion in the presence or

absence of ovarian hormones.

The results are summarized as fellows.

1. Perfusion of estrogen increased the pancreatic flow as well as CCK-stimulated

amylase secretion.

2. CCK-stimulated secretion of amylase was increased by perfusion with

progesterone and over 10**-6 M concentration secretin-stimulated pancreatic flow

was also increased.

3. The effect of progesterone on the exocrine secretory function was not enhanced

or inhibited by background perfusion of estrogen in isolated perfused pancreas.

These results suggest that ovarian hormones exert significant influence on the

exocrine secretory function, both enzyme and waters of the pancreas and this effect

might be exerted by direct effect on the pancreas.

[영문]

Regulation of pancreatic exocrine secretion is comprised of a complex interplay between hormonal and nervous systems. It has been claimed that steroid hormones may participate in maintaining the exocrine function of the pancreas. Corticosteroids and ovarian hormones are synthesized from the same precursor, cholesterol, in vivo and they are important regulators of homeostasis.

Though the effects of corticosteroids on pancreatic function are not consistant, it is widely accepted that the glucocorticoid inhibits the secretory function whereas mineralocorticoid stimulates.

Several studies have suggested that ovarian hormones exert significant influence on the exocrine pancreas. And pancreatic function of exocrine cells may be regulated by estrogen and estrogen-binding protein. Also, it was reported that

protesterone increased both the cellular content of amylase and cytoplasmic mRNA of rat tumor cell line AR 42J.

In the present study, attempt was made to examine the direct effects of estrogen and progesterone on exocrine function employing saline perfused isolated cat pancreas.

Mongrel cats, of both sexes weighing about 1.5Kg , were anesthetized with secobarbital (30mg/kg, ip), then the pancreas was isolated and perfused with Krebs Ringer bicarbonate buffer(KRBB) gassed with 95% 0^^2-5% CO^^2 at the rate of 6

ml/min. Ovarian hormone, estrogen or progesterone was added to the perfusate for 30 minutes. Submaximal dose of secretin was infused to maintain pancreatic flow and cholecystokinin was injected to evoke the enzyme secretion in the presence or

absence of ovarian hormones.

The results are summarized as fellows.

1. Perfusion of estrogen increased the pancreatic flow as well as CCK-stimulated amylase secretion.

2. CCK-stimulated secretion of amylase was increased by perfusion with progesterone and over 10**-6 M concentration secretin-stimulated pancreatic flow was also increased.

3. The effect of progesterone on the exocrine secretory function was not enhanced or inhibited by background perfusion of estrogen in isolated perfused pancreas.

These results suggest that ovarian hormones exert significant influence on the exocrine secretory function, both enzyme and waters of the pancreas and this effect might be exerted by direct effect on the pancreas.