title: Gestational length affects a change in the transepithelial voltage and the rNKCC2 expression pattern in the ascending thin limb of Henle's loop.
abstract: To examine whether the functional and morphologic conversion of the neonatal ascending thin limb (ATL) of Henle's loop is related to gestational length, we evaluated the transepithelial voltages (Vts) of ATLs in perinatal mouse, hamster, rabbit, and rat kidneys. In isolated microperfused tubule preparations, Vts of neonatal ATLs were 23.8 +/- 1.4 in mouse, 25.7 +/- 2.2 in hamster, and 18.2 +/- 1.6 mV in rabbit. The influence of gestational length on the Vts and rat Na-K-Cl cotransporter (rNKCC2) expression pattern was also examined in perinatal rats subjected to a prolonged gestation due to either a daily s.c. injection of 5 mg progesterone or ligation of the extremities of the uterine horn. Vts of d 3 neonates were 2.9 +/- 1.0 (p < 0.0001 versus d 0); Vts of d 23 fetuses subjected to ligation were 4.9 +/- 0.8 (p < 0.005 versus d 0); and Vts of d 23 fetuses given progesterone were 3.4 +/- 1.7 mV (p < 0.001 versus d 0). rNKCC2 expression tended to disappear in the renal papillae of d 23 fetuses. Our data demonstrate that the perinatal conversion of the ATL is a phenomenon commonly observed among rodents; furthermore, it is dependent on the gestational length, but unrelated to the birth process.
authors.affiliation: Department of Pediatrics, Tohoku University Graduate School of Medicine, Sendai, Japan 980-8574.
authors.forename: Minako
authors.initials: M
authors.lastname: Nishino
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Morimoto
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nishio
authors.forename: Ulviyya F
authors.initials: UF
authors.lastname: Aslanova
authors.forename: Elnur I
authors.initials: EI
authors.lastname: Farajov
authors.forename: Naonori
authors.initials: N
authors.lastname: Kumagai
authors.forename: Noriko
authors.initials: N
authors.lastname: Sugawara
authors.forename: Shori
authors.initials: S
authors.lastname: Takahashi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ohsaga
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Maruyama
authors.forename: Shigeru
authors.initials: S
authors.lastname: Tsuchiya
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Kondo
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D006224:Cricetinae; D005260:Female; D005455:Fluorescent Antibody Technique; D005865:Gestational Age; D008138:Loop of Henle / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology*; D008564:Membrane Potentials; D051379:Mice; D008810:Mice, Inbred C57BL; D011247:Pregnancy; D011270:Pregnancy, Animal; D011374:Progesterone / Q000008:administration & dosage; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D028021:Sodium-Potassium-Chloride Symporters / Q000378:metabolism*; D064466:Solute Carrier Family 12, Member 1
chemical_list: C578715:Slc12a1 protein, mouse; C578716:Slc12a1 protein, rat; D028021:Sodium-Potassium-Chloride Symporters; D064466:Solute Carrier Family 12, Member 1; D011374:Progesterone