Local umbilical cord blood renin-angiotensin system.
Local bone marrow (BM) renin-angiotensin system (RAS) is an autocrine-paracrine system affecting normal and neoplastic hematopoiesis. Angiotensin II type 1a (AT1a) receptors are present on the CD34(+) hematopoietic stem cells (HSC). Angiotensin II stimulates the proliferation and differentiation of the HSC populations through the activation of AT1 receptors on HSC. Umbilical cord blood (UCB) is a rich source of HSC. The existence of a complete local UCB RAS has not been previously investigated. In this study, local synthesis of the major RAS components, namely, angiotensin-converting enzyme (ACE), renin, and angiotensinogen, was identified by demonstrating their corresponding mRNAs using quantitative reverse transcriptase polymerase chain reaction (RT-PCR) in human UCB. Local RAS could regulate cellular growth in a variety of tissues including the BM. Major RAS peptides can exert significant effects on primitive pluripotential HSC populations. Further studies should focus on the interactions between possible autocrine, paracrine, endocrine, and intracrine actions of the local UCB RAS and growth, engraftment, differentiation, and plasticity functions of HSC of UCB origin.
Goker
Hakan
H
Department of Hematology, Hacettepe University Medical School, Sihhiye, Ankara 06100, Turkey. hgoker1@yahoo.com
Haznedaroglu
Ibrahim C
IC
Beyazit
Yavuz
Y
Aksu
Salih
S
Tuncer
Serdar
S
Misirlioglu
Muge
M
Bayramoglu
Fatma
F
Kekilli
Murat
M
Büyükasik
Yahya
Y
Sayinalp
Nilgun
N
Ozcebe
Osman
O
Dundar
Semra
S
Mollamahmutoglu
Leyla
L
D000804:Angiotensin II / Q000096:biosynthesis; D000808:Angiotensinogen / Q000096:biosynthesis; D019898:Autocrine Communication / Q000502:physiology; D049109:Cell Proliferation; D005260:Female; D005312:Fetal Blood / Q000166:cytology / Q000378:metabolism*; D006410:Hematopoiesis / Q000502:physiology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D019899:Paracrine Communication / Q000502:physiology; D007703:Peptidyl-Dipeptidase A / Q000096:biosynthesis; D011247:Pregnancy; D012083:Renin / Q000096:biosynthesis; D012084:Renin-Angiotensin System / Q000502:physiology*
D000808:Angiotensinogen; D000804:Angiotensin II; D007703:Peptidyl-Dipeptidase A; D012083:Renin