Biomaterial Database

Fetal compensatory renal growth due to unilateral ureteral obstruction. 1993

C A Peters, and R C Gaertner, and M C Carr, and J Mandell

Department of Surgery, Children's Hospital, Boston, Massachusetts.

To determine whether fetal compensatory renal growth occurs in response to early gestational unilateral renal obstruction and to help elucidate the characteristics of this response, a fetal lamb model was developed in which unilateral ureteral obstruction was created at 60 days of gestation (term 135 to 140 days) and the effects of the obstruction were studied at varying periods thereafter. Kidneys were retrieved at 2 weeks (75 days in 3 cases), 5 weeks (95 days in 4) and 10 weeks (135 days in 9) after obstruction, weighed and preserved for histology and biochemical studies. Deoxyribonucleic acid (DNA), ribonucleic acid and protein were quantitated using standard assays. Morphometric studies to estimate glomerular number were performed using standard stereological methods. Contralateral kidney weight was increased compared to normals in 55 cases at all ages. The relative difference increased from 75 to 95 days. The fractional increase at 135 days (49.5%, p < 0.001 versus normal) was not different from 95 days (46.4%, p = 0.87), indicating that growth rate acceleration occurred predominantly before 95 days. Total renal DNA was increased above normal at each time point, with an ultimate increment proportionate to weight. Protein concentration was unchanged, suggesting that weight increase was not due to changes in renal water. Protein/DNA ratios were unchanged, indicating a predominantly hyperplastic process. Ribonucleic acid/DNA ratios decreased, possibly indicating a high rate of proliferation. Total glomerular number at term did not increase with in utero compensatory renal growth. Unilateral ureteral obstruction created early in gestation produced compensatory renal growth of the intact kidney in the fetal lamb. This process demonstrates an early but transient growth rate acceleration, hyperplasia and no increase in total glomerular or nephron number. The occurrence of compensatory renal growth in the fetal kidney with minimal functional renal demand would suggest that its mechanisms may be independent of functional demand. This model is unique and well suited to study compensatory renal growth.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D009929	Organ Size	The measurement of an organ in volume, mass, or heaviness.	Organ Volume,Organ Weight,Size, Organ,Weight, Organ
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D005260	Female		Females
D005333	Fetus	The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.	Fetal Structures,Fetal Tissue,Fetuses,Mummified Fetus,Retained Fetus,Fetal Structure,Fetal Tissues,Fetus, Mummified,Fetus, Retained,Structure, Fetal,Structures, Fetal,Tissue, Fetal,Tissues, Fetal
D000222	Adaptation, Physiological	The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.	Adaptation, Physiologic,Adaptations, Physiologic,Adaptations, Physiological,Adaptive Plasticity,Phenotypic Plasticity,Physiological Adaptation,Physiologic Adaptation,Physiologic Adaptations,Physiological Adaptations,Plasticity, Adaptive,Plasticity, Phenotypic
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012313	RNA	A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	RNA, Non-Polyadenylated,Ribonucleic Acid,Gene Products, RNA,Non-Polyadenylated RNA,Acid, Ribonucleic,Non Polyadenylated RNA,RNA Gene Products,RNA, Non Polyadenylated
D012756	Sheep	Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.	Ovis,Sheep, Dall,Dall Sheep,Ovis dalli