G292 ¼¼Æ÷¿¡¼ ¼¼Æ÷¸· ½ÅÀåÀ¸·Î È°¼ºÈµÇ´Â K+ Åë·ÎÀÇ Æ¯¼º
Properties of stretch-activated K+ channels in an G292 osteoblast-like cell
¼Ò¼Ó »ó¼¼Á¤º¸
ÀÌ»ó±¹/Sang Gook Lee
¹Ú¼öº´/Á¤µ¿±Ù/¼´öÁØ/Soo Byung Park/Dong Keun Jung/Duk Joon Suh
KMID : 0361920000300020194
Abstract
kabstract :
º» ¿¬±¸¿¡¼´Â ÀÎü °ñÁ¾¾ç¿¡¼ À¯·¡ÇÑ G292 ¼¼Æ÷¸¦ ÀÌ¿ëÇÏ¿© ¾Ð·ÂÀ¸·Î ¼¼Æ÷¸·À» ½ÅÀå
(stretch)½ÃÄ×À» ¶§ K+ Åë·ÎÀÇ Àü±âÀû È°¼º º¯È¸¦ ¿¬±¸ÇÏ¿´´Ù. ¹è¾çµÈ ¼¼Æ÷
¿¡¼ À¯¸®Àü±ØÀ» ÀÌ¿ëÇÏ¿© ¼¼Æ÷¸· ³»ÃøÀÌ À¯¸®Àü±ØÀÇ ¿ÜºÎ·Î ÇâÇϵµ·Ï inside-out patch¸¦
¾ò¾î ´ÜÀÏÀÌ¿ÂÅë·ÎÀü·ù¸¦ ¸·Àü¾Ð°íÁ¤¹ý(patch clamp recording)À¸·Î ±â·ÏÇÏ¿´´Ù.
G292 ¼¼Æ÷ÀÇ ¼¼Æ÷¸· ³»¿Ü¿¡ 140 mM KCI ¿ë¾×ÀÌ ÀÖ´Â »óÅ¿¡¼ À¯¸®Àü±Ø³» Àü¾ÐÀ» -80
mV·Î °íÁ¤ÇßÀ» ¶§ Àüµµ¼ºÀÌ 270 27 pS, 113 12 pS, 48 8 pSÀÎ 3°¡Áö Á¾·ùÀÇ
K+ Åë·Î¸¦ °üÂûÇÏ¿´´Ù. Àüµµ¼ºÀÌ ³·Àº 48 pSÀÇ K+ Åë·Î´Â ¸ð
µç ¼¼Æ÷¸·¿¡¼ °üÂûÇÏ¿´À¸¸ç 270 pS ¹× 113 pSÀÇ K+ Åë·Î´Â ÀϺΠ¼¼Æ÷¿¡¼
¸¸ °üÂûÇÏ¿´´Ù. 48 pSÀÇ K+ Åë·Î´Â ¼¼Æ÷¸· ¿ÜÃø¿¡ À½ÀÇ Àü¾ÐÀ» °¡Çϸé È°¼º
ÈµÇ°í ¾çÀÇ Àü¾ÐÀ» °¡Çϸé È°¼ºÈµÇÁö ¾Ê´Â ¿ÜÇ⼺ Á¤·ùƯ¼ºÀ» º¸¿´´Ù. ¼¼Æ÷¸· ¿ÜÃø¿¡ À½
¾ÐÀ» °¡Çϸé 48 pSÀÇ K+ Åë·Î´Â È°¼ºÈµÇ¾úÀ¸¸ç ÀÌ¿Â Åë·Î°¡ ¿¸®´Â È®·ü
(Popen)ÀÌ °¡ÇÏ´Â ¾Ð·Â¿¡ ºñ·ÊÇÏ¿© Áõ°¡ÇÏ¿´´Ù.
ÀÌ·¯ÇÑ °á°ú´Â G292 ¼¼Æ÷ÁÖ¿¡ 3°¡Áö Á¾·ùÀÇ K+ Åë·Î°¡ Á¸ÀçÇϸç Àüµµ¼ºÀÌ
³·Àº 48 pSÀÇ K+ Åë·Î¸¸ÀÌ ¼¼Æ÷¸· ½ÅÀå¿¡ ÀÇÇÏ¿© Á÷Á¢ÀûÀ¸·Î È°¼ºÈµÇ´Â Ư
¼ºÀ» º¸¿´´Ù. ÀÌ·¯ÇÑ K+ Åë·ÎÀÇ È°¼ºÈ´Â ¼¼Æ÷°¡ ±â°èÀû ÀÚ±ØÀ» ¹Þ¾Æ ¼¼Æ÷¸·
ÀÌ ½ÅÀåµÇ¸é ¼¼Æ÷¸·Àü¾ÐÀ» °úºÐ±Ø½ÃÅ°¸ç Á¶°ñ¼¼Æ÷¿¡¼ ±â°èÀû °¨¼ö±â·Î¼ÀÇ ±â´ÉÀ» ¼öÇàÇÏ
¿© Á¶°ñ¼¼Æ÷ÀÇ °ñ°³Á¶¿¡ °ü¿©ÇÒ °ÍÀ¸·Î ÃßÃøµÈ´Ù.
#ÃÊ·Ï#
-Abstract-
K+ -selective ion channels were studied in excised inside-out membrane
patches from human osteoblast-like cells(G292). There classes of K+
channels were present and could be distinguished on the basis of conductance.
Conductances were 270 27 pS, 113 12 pS, 48 8 pS according to their approximate
conductances in symmetrical 140 mM KCI saline at holding potential of -80 mV. It was
found that the small conductance (48 pS) K+ channel activation was
dependent on membrane voltage. In current-voltage relationship, small conductance
K+ channel showed outward rectification, and it was activated by the
positive potential inside the membrane. In recordings, single channel currents were
activayed by a negative pressure outside the membrane. The membrane pressure
increased Popen of the K+ channel in a pressure-dependent
manner.
In the excised-patch clamp recordings, G292 osteoblast-like cells have been shown to
contain three types of K+ channels. Only the small conductance (48 pS)
K+ channel is sensitive to the membrane stretch. These findings suggest
that a hyperpolarzing current, mediated in part by this channel, may be associated with
early events during the mechanical loading of the osteoblast. In G292 osteoblast-like
cells, K+ channel is sensitive to membrane tension, and may represent a
unique adaptation of the bone cell membrane to mechanical stress.
Å°¿öµå
G292 ¼¼Æ÷; ¼¼Æ÷¸· ½ÅÀå; K; Åë·Î; G292 osteoblast-like cell; Stretch-activated K; channel;
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