Effect of vasoactive intestinal peptide on pulmonary surfactants phospholipid synthesis in lung explants.
OBJECTIVE
To investigate the effect of vasoactive intestinal peptide (VIP) on pulmonary surfactants (PS) phospholipid synthesis in cultured lung explants.


METHODS
Lung explants were cultured with serum-free medium, [methyl-3H]choline incorporation, total phospholipid, phosphatidylcholine, activity of choline-phosphate cytidylyltransferase (CCT) and CCTalpha mRNA level in lung explants were determined.


RESULTS
(1) VIP (10(-10)-10(-7) mol/L) for 16 h promoted [methyl-3H]choline incorporation in dose dependence and VIP (10(-8) mol/L) for 2 h-16 h promoted [methyl-3H]choline incorporation in time dependence. (2) VIP (10(-8) mol/L) enhanced the contents of total phospholipids and phosphatidylcholine in lung explants. (3) VIP (10(-10)-10(-7) mol/L) elevated microsomal CCT activity of lung explants in dose dependence. (4) VIP (10(-8) mol/L) increased expression of CCTalpha mRNA in lung explants and alveolar type II cells (ATII). (5) [D-P-Cl-Phe(6)-Leu(17)]-VIP (10(-6) mol/L), a VIP receptors antagonist, abolished the increase of [3H]choline incorporation, microsomal CCT activity and CCTalpha mRNA level induced by VIP (10(-8) mol/L) in lung explants.


CONCLUSIONS
VIP could enhance synthesis of phosphatidylcholine, the major component of pulmonary surfactants by enhancing microsomal CCT activity and CCTalpha mRNA level via VIP receptor-mediated pathway.
Li
Lian
L
Department of Physiology, Xiangya School of Medicine, Central South University, Changsha 410078, China.
Luo
Zi-qiang
ZQ
Zhou
Fu-wen
FW
Feng
Dan-dan
DD
Guang
Cha-xiang
CX
Zhang
Chang-qing
CQ
Sun
Xiou-hong
XH
D000818:Animals; D002478:Cells, Cultured; D002794:Choline / Q000096:biosynthesis; D019916:Choline-Phosphate Cytidylyltransferase / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D008168:Lung / Q000166:cytology / Q000201:enzymology*; D008297:Male; D008861:Microsomes / Q000201:enzymology; D010713:Phosphatidylcholines / Q000096:biosynthesis; D010743:Phospholipids / Q000096:biosynthesis; D011663:Pulmonary Surfactants / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D018005:Receptors, Vasoactive Intestinal Peptide / Q000037:antagonists & inhibitors; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*
D007527:Isoenzymes; D010713:Phosphatidylcholines; D010743:Phospholipids; D011663:Pulmonary Surfactants; D012333:RNA, Messenger; D018005:Receptors, Vasoactive Intestinal Peptide; C048507:vasoactive intestinal peptide, 4-chloro-Phe(6)-Leu(17)-; D014660:Vasoactive Intestinal Peptide; D019916:Choline-Phosphate Cytidylyltransferase; D002794:Choline