Development of Elastic Fibres in the Upper Urinary Tract

Abstract

The development of elastic fibres in the upper urinary tract was studied in 31 fetuses ranging in ovulatory age from 10 to 24 weeks using special staining techniques for elastic fibres. The number, orientation and distribution of elastic fibres are described and correlated with age, ureteric level, and fetal weight. Significantly, before 10 weeks, elastic fibres were few in number, poorly developed, and randomly arranged. After 12 weeks, these fibres became more numerous at each level of the urinary tract, and were seen to develop specific orientation. The findings are described and potential clinical implications are discussed.

Elastic fibres in the vesicourethral junction and urethra of the guinea pig: quantification with computerised image analysis

“…Elastic fibres are also present in structures of the urinary tract but have been studied less extensively except by Escala et al (1989), who examined the development and distribution of elastic fibres in the upper urinary tract of the human fetus and by Augsburger (1997), who investigated the elastic fibre system of the female canine urethra. Prior to these studies, the distribution and probable role of elastic fibres in the urethra itself had received only brief and passing mention in anatomical studies of the cat (Cullen et al 1983), dog (Augsburger et al 1993) and…”

Rare case of non-refluxing non-obstructive megaureter in an adult

“…The foetal kidney produces four to six times more urine before delivery than afterward [7], possibly causing ureteral dilatation in a manner similar to that seen with diabetes insipidus. Another contributing factor may be the increased compliance of the foetal ureter, which may result from differences in the deposition and orientation of elastin, collagen and other matrices that occur at various rates in the developing foetal ureter [8]. Dilatation may also be due to transient or partial anatomical or functional obstructions, which spontaneously improve with postnatal development, such as persistent ureteral folds [9] or delayed development of normal peristalsis.…”

Anatomical Relationships between Testis and Epididymis during the Fetal Period in Humans (10–36 Weeks Postconception)

“…The fetuses were well preserved and none of them had any kind of detectable congenital malformation [13]. The gestational age of the fetuses ranged between 10 and 36 weeks postconception and was estimated according to the foot length criteria [14, 15, 16, 17, 18, 19, 20, 21]. …”