Developmental and Compensatory Renal Growth in the Guinea Pig

Publisher Website
Google Scholar
Abstract
Postnatal renal growth in the guinea pig was studied in terms of cell size and number by estimation of renal nucleic acids. The renal content of RNA and DNA increased until about 3 months of age, when the kidneys themselves virtually ceased growing. By relating kidney weight to DNA content, it was found that average renal cell size reaches a maximum within 3–5 weeks of birth; after this renal growth is achieved purely by hyperplasia. When adult guinea pigs (3–4 months old) were subjected to unilateral nephrectomy, the remaining kidney underwent compensatory growth; after 6 weeks it was 42 % bigger than that of littermate control or sham-operated animals. Unilateral nephrectomy of guinea pigs 4–6 days old produced a greater response – a 59 % weight increase after 6 weeks. The renal weight increases were associated with similar increases in RNA content, but DNA content did not increase until the 2nd postoperative week, and then only by a relatively small amount. The increases in renal DNA content in newborn animals were not significantly different from those in adults. It is concluded that the degree of compensatory renal hyperplasia is the same in newborn and adult guinea pigs and that the extra response of neonates is due to cellular hypertrophy; thus the factor(s) controlling compensatory growth cannot act merely by regulating the rate of cell division.

This publication has 0 references indexed in Scilit: