Vol.12, No 2, 2005 pp. 61 - 69
UC 616.61
AGE RELATED ANATOMICAL AND FUNCTIONAL
CHARACTERISTICS
OF HUMAN KIDNEY
Rade Čukuranović, Slobodan Vlajković
Institute of Anatomy, Medical School, University of Niš, Serbia and
Montenegro
E-mail: rade.c@EUnet.yu
Summary. Development of the human kidney begins at the end of
the
first month, and the kidney becomes functional in the course of the
second
month of antenatal life. In the last trimester, the fetal kidney
already
manifests first involutive changes. From then on to its adult maturity,
the kidney is characterised by intensive processes of maturation, but
also
evident involutive changes. The dynamism of these changes, however, is
different in certain life ages. The antenatal period is characterised
by
intensive processes of nephrogenesis, realised in three successive
phases
of renal development: pronephros, mesonephros, and metanephros. The
first
two changes represent a temporary system, while the third stands for a
permanent system of excretion, that is, a definitive kidney. The
functioning
of kidneys, though not necessary in the antenatal stadium, indicates
their
excretory, homeostatic and endocrine roles, and signifies the
maturation
process. After birth, there is a further process of structural and
functional
maturation of the kidneys. With a definitive number of nephrones at
birth,
renal mass increases at the expense of growth of certain nephrone
structures
and interstitium. The kidney reaches its full anatomical and functional
maturity by the end of the third decade of life. From then on, the
kidney
is characterised by involutive changes of varying intensity. By the end
of the sixth decade these changes are slow; afterwards, to the end of
life,
they show a trend of very rapid progression, and are a consequence
primarily
of the reduced renal perfusion. In spite of that, under normal
conditions
they do not show signs of renal insufficiency even in a well-advanced
age.
The involutive renal changes can be separate, but they can coincide
with
corresponding renal diseases. In some individuals this can result in a
progressive failure of renal functions in an advanced age.
Key words: Age, anatomy, function, human kidney
UZRASNE ANATOMSKE I FUNKCIONALNE
KARAKTERISTIKE
BUBREGA ČOVEKA
Kratak sadržaj: Razviće bubrega čoveka započinje krajem prvog, a
njegove prve funkcije već u toku drugog meseca prenatalnog života. U
zadnjem
trimestru fetalni bubreg pokazuje i prve involutivne promene. Nadalje,
sve do dostizanja adultnosti, bubreg karakterišu intenzivni procesi
maturacije
ali i evidentne involutivne promene. Dinamika ovih procesa se, međutim,
razlikuje u pojedinim uzrasnim dobima. Prenatalni period karakterišu
intenzivni
procesi nefrogeneze, koji se ostvaruju kroz tri sukcesivne razvojne
forme
bubrega: pronefros, mezonefros i metanefros. Prve dve forme
predstavljaju
privremene, a treća trajni ekskretorni sistem, tj. definitivni bubreg.
Funkcionisanje bubrega, iako nije neophodno u prenatalnom stadijumu,
ukazuje
na njihovu ekskretornu, homeostatsku i endokrinu ulogu i odraz je
procesa
sazrevanja. Po rođenju, bubrezi se odlikuju daljim procesima strukturne
i funkcionalne maturacije. Sa, na rođenju, definitivnim brojem nefrona
oni uvećavaju svoju masu na račun rasta pojedinih struktura nefrona i
intersticijuma.
Punu anatomsku i funkcionalnu zrelost bubreg dostiže krajem treće
decenije
života. Nadalje bubreg odlikuju involutivne promene različitog
intenziteta.
Do kraja šeste decenije ove promene su spore; potom, sve do kraja
života
imaju trend veoma ubrzane progresije i posledica su, pre svega,
smanjene
perfuzije bubrega. Uprkos tome, u normalnim uslovima i u najdubljoj
starosti
ne pokazuju znake funkcionalne insuficijencije. Involutivne promene na
bubrezima mogu biti zasebne, a mogu se i superponirati sa odgovarajućim
bubrežnim bolestima, što kod izvesnog broja osoba u poodmaklim godinama
može dovesti do progresivnog gubitka bubrežnih funkcija.
Ključne reči: Uzrast, anatomija, funkcija, bubreg čoveka
