Journal of Andrology, Vol. 23, No. 5, September/October 2002
Copyright © American Society of Andrology
Ultrastructural Features of the Vas Deferens From Patients Undergoing Vasectomy and Vasectomy Reversal
SERO ANDONIAN*,
KEITH JARVI
,
ARMAND ZINI
AND
LOUIS HERMO*
From the * Department of Anatomy and Cell Biology,
McGill University, Montréal, Québec, Canada; and the
Division of Urology, Department of Surgery,
Mount Sinai Hospital, Toronto, Ontario, Canada.
| Correspondence to: Dr Louis Hermo, Department of Anatomy and Cell Biology,
McGill University, 3640 University St, Montréal, Québec, Canada
H3A 2B2 (e-mail:
lhermo{at}med.mcgill.ca). |
Despite more than 30 million vasectomies, the ultrastructural features of
the epithelium of the vas deferens (VD) of healthy fertile men, as well as the
effects of vasectomy at both proximal (testicular) and distal (abdominal)
regions of the VD relative to the initial site of incision, have yet to be
fully elucidated. In the present study, the VD from 22 fertile men undergoing
vasectomy and 7 vasectomized men undergoing vasectomy reversal were examined
by light and transmission electron microscopy. In fertile men, aside from
cellular organelles involved in endocytosis and merocrine secretion, the
epithelial principal cells showed protrusions of their apical cytoplasm
between adjacent microvilli, referred to as "apical blebs." The
latter contained solely numerous ribosomes/polysomes and few endoplasmic
reticulum (ER) cisternae, unlike the presence of lysosomes, lipofuscin
granules, mitochondria, and the Golgi apparatus in the apical principal cell
cytoplasm, suggesting the segregation of organelles within blebs. Many apical
blebs presented a bulbous extremity with a thin stalklike attachment
connecting them to the apical principal cell surface, while others appeared to
be isolated and well removed from it, suggesting that blebs are capable of
detaching and being liberated into the lumen. We hypothesize that apical blebs
represent a type of secretion, referred to as "apocrine
secretion." In men undergoing vasectomy reversal, the VD proximal
(testicular) to the vasectomy site showed a reduction in the size of principal
cells and their microvilli and in the number of apical blebs. In contrast, the
lumen of the VD distal (abdominal) to the vasectomy site was virtually
abolished, with the epithelium reduced to a flattened layer of cells showing a
paucity of organelles and no apical blebs, suggesting that these cells become
undifferentiated in the absence of seminal fluids. Taken together, these data
may explain, in part, the decreased pregnancy rate noted after vasectomy
reversal despite a patent anastomosis.
Key words: Electron microscopy, principal cells, apical blebs, apocrine secretion
Copyright © 2002 by The American Society of Andrology.