Pancreas ÃÑ·Ð
1. ºÐºñ: 1500-3000 ml/day, isoosmotic alkaline fluid(pH>8.0)
¾à 20¿©Á¾ÀÇ enzyme & zymogen ÇÔÀ¯
À§Àå°üÀÇ ¼ÒÈÀÛ¿ë¿¡ ÇÊ¿äÇÑ È¿¼Òµé°ú À̵é È¿¼Ò°¡ ÀûÀýÇÑ ÀÛ¿ëÀ» ÇÒ¼ö ÀÖ´Â
ÀûÁ¤ pH ȯ°æÀ» Á¦°øÇÑ´Ù.
2. ÃéÀå¾× ºÐºñÁ¶Àý
exocrine pancreas : hormonal & neural system ÀÇ »óÈ£ÀÛ¿ë¿¡ ÀÇÇØ Á¶ÀýµÈ´Ù.
1) secretin: À§»ê(Gastric acid)ÀÌ secretinºÐºñÀÇ ÁÖ ÀڱؿøÀÌ´Ù.
½ÊÀÌÁöÀå°ú °øÀå¿¡¼ À§»êÀÇ ÀÚ±ØÀ¸·Î pH°¡ 4.5°¡ µÉ ¶§ ºÐºñµÇ±â ½ÃÀÛÇÏ¿©
water, electrolyte°¡ dzºÎÇÑ ÃéÀå¾× ºÐºñ¸¦ ÀÚ±ØÇÑ´Ù.
¹®> secretinºÐºñ¿¡ ÇÊ¿äÇÑ ÀڱؿøÀº? Gastric acid
secretinºÐºñ¿¡ ÇÊ¿äÇÑ pH threshold? 4.5
2) CCK : ½ÊÀÌÁöÀå°ú °øÀå¿¡¼ long chain fatty acid, essential amino acid(tryptophan,
phenylalanine, valine, methionine) ¹× gastric acidÀÚüÀÇ Àڱؿ¡ ÀÇÇØ ºÐºñµÈ´Ù.
EnzymeÀÌ Ç³ºÎÇÑ ÃéÀå¾×À» ºÐºñÇϵµ·Ï ÀÚ±ØÇÑ´Ù.
3) parasympathetic nervous system(vagus nerve)
- secretin°ú CCK¿¡ ÀÇÇÑ enzyme secretionÀº afferent & efferent vagal pathway¿¡ ÀÇÇØ
Á¶ÀýµÇ°í water, bicarbonate secretionÀº hormonal effect¿¡ ÀÇÇØ Á¶ÀýµÈ´Ù.
- VIP, secretin agonistµµ vagal stimulation¿¡ ÀÇÇØ ºÐºñµÈ´Ù.
4) Bile saltsµµ ÃéÀå¾× ºÐºñ¸¦ ÀÚ±ØÇÑ´Ù.
5) Somatostatin : ¿©·¯±ºµ¥¿¡¼ ÀÛ¿ëÇϸç ÃéÀå¾× ºÐºñ¸¦ ¾ïÁ¦ÇÑ´Ù.
6) Nitric oxide : Áß¿äÇÑ neurotransmitterÀÌÁö¸¸ ¾ÆÁ÷ ¿ÏÀüÈ÷ ¹àÇôÁöÁö ¾Ê¾Ò´Ù.
<Á¤¸®>
parasympathetic regulation: secretin, CCK, VIP
hormonal regulation: water, bicarbonate
¸ðµÎ ÃéÀå¾× ºÐºñ¸¦ ÀÚ±ØÇϳª somatostatinÀº ÃéÀå¾× ºÐºñ¸¦ ¾ïÁ¦ÇÑ´Ù.
µû¶ó¼ somatostatinÀ» ÃéÀåÁúȯ Ä¡·áÁ¦·Î »ç¿ëÇÑ´Ù.
3. Water & Electrolyte
Bicarbonate : the ion of primary physiologic importance
120-300 mmol/d
À§»êÀ» ÁßÈÇÏ¿© ÃéÀå È¿¼Ò°¡ ÇÊ¿ä·Î ÇÏ´Â ÀûÁ¤ pH¸¦ À¯ÁöÅä·Ï ÇÑ´Ù.
4. Enzyme secretion
amylolytic, lipolytic, proteolytic enzymeÀ» ºÐºñÇÑ´Ù.
1) amylolytic enzyme(amylase)
starch -> oligosaccharide, disaccharide·Î °¡¼öºÐÇØ
2) lipolytic enzyme : lipase, phospholipase A, cholesterol esterase
bile salt´Â lipase¸¦ ¾ïÁ¦Çϰí phospholipase A, cholesterol esterase´Â Ȱ¼ºÈ½ÃŲ´Ù.
3) Proteolytic enzyme
i) endopeptidase(trypsin, chymotrypsin)
ii) exopeptidase(carboxypeptidase, aminopeptidase)
ÀÌ proteolytic enzymeÀº inactive precursors(zymogen)·Î ºÐºñµÈ´Ù.
½ÊÀÌÁöÀå Á¡¸·¿¡ ÀÖ´Â enterokinase´Â trypsinogenÀÇ lysine-isoleucine bond¸¦ ²÷¾î
trypinÀ» Çü¼ºÇÑ´Ù. ÀÌ·¸°Ô Çü¼ºµÈ trypsinÀº casecade phenomenon¿¡¼ proteolytic
zymogenÀ» Ȱ¼ºÈ½ÃŲ´Ù.
*¸ðµç ÃéÀåÈ¿¼ÒµéÀº ¾ËÄ®¸® ȯ°æÀÌ ÀûÁ¤ pHȯ°æÀÌ´Ù.
5. Autoprotection
precursor formÀ¸·Î ÀÖ´Â protease packingÇϰí protease inhibitor¸¦ ÇÕ¼ºÇÏ¿©
autodigestionÀ» ¹æÁöÇÑ´Ù. ÀÌ·¯ÇÑ protease inhibitor´Â acinar cell, pancreatic secretion
¿¡¼ ¹ß°ßµÇ¸ç plasma¿¡¼ ¥á1, ¥á2-globulin fractionÀ¸·Î ³ªÅ¸³´Ù.