The development of the seminal vesicles in man

Abstract

In reviewing the literature on the embryology of the seminal vesicles one finds a surprising lack of any detailed or accurate study covering their course of development in foetal life. There are many references to the time of their initial appearance, but from that time until birth, or in fact until adult life, there are very few observations. The work of Pallin ('01) on the development of the prostate and seminal vesicles is unquestionably the most complete.Kolliker ('79) stated that the vesicles have their beginning in the third month of foetal life as offshoots from the proximal portion of the Wolffian ducts. Mihalkovics ('85) found that at about the fifth month of intra-uterine life the evaginations from the deferent ducts, going to form the seminal vesicles, proceeded first in a horizontal, then in an upward curving direction. Minot ('92) stated that the vesicles do not attain a length of 1 nun. until about the fifth month of foetal life. 0. Schultz ('97) wrote that they appear at the end of the third month as outgrowths of the lower part of the Wolffian ducts, and are then simple, hollow, pear-shaped appendages about 1 mm. long. Heisler ('99), in his text-book, stated that from the caudal end of the Wolffian duct there arises a pouch-like evagination, which later becomes the seminal vesicle. Pallin ('Ol), reporting his studies on the development of the prostate and seminal vesicles in man and in the lower aniwls, found that they appear at the third month of foetal life. They are noted first as longitudinal folds con-395 TEB AMERICAN XOURXAL OF ANATOMY, VOL. 24, NO. 4 NOVEMBER. 1018 DEVELOPMENT O F SEMINAL VESICLES 1N MAN 397rump length, and the ages of the specimens were determined according to the figures in the table of classification in Keibel and Mall's Human Embryology. Before taking up the discussion of the various specimens it might be well to define the terms used to describe the direction of growth of the vesicles. Anterior refers to the cranial end of the body; ventral, to the region of the abdominal wall, and dorsal, to the back or vertebral aspect. The lateral measurements were taken by means of a micrometer eyepiece on a microscopic stage. The anterior posterior measurements were m d e by counting the number of sections, which were all cut of a known thickness and every section saved for study. The reconstructed drawings of the eight specimens, showing their dorsoventral view in two diameters with varied configurations, were made from the superimposed serial sections. These sections were reproduced under a magnification of fifty diameters to insure greater accuracy, and transferred to millimeter paper from which the reconstructed diagrams were made. The drawings were then reduced to a size suitable for illustrations. Fetuses about 80 mm. longThis stage is represented by specimen no. 76% of the Carnegie Collection, length 80.3 mm., and illustrated by figures 1, 2, and 3. In this specimen the beginning of the seminal vesicles and their relation to the ampullae of the deferent ducts, to the trigon...

Three‐dimensional reconstruction of the luminal structure of human seminal vesicle

“…Embryologically, the seminal vesicles are first observed in mesonephric (Wolffian) ducts in the 13th week of fetal life (Watson, 1918; Ernst et al ., 2011). After the development of fetal testes, released androgen hormone affects the development of the seminal vesicles (Thomson and Marker, 2006).…”

“…In the 14th week, the seminal vesicles begin to develop to the primitive form characterized by sacculation, evagination and diverticula. By 21 weeks, they approach the form of the adult seminal vesicles (Watson, 1918).…”