A potential role for cadmium in the etiology of varicocele-associated infertility.
OBJECTIVE
To determine whether mannose ligand receptor and acrosome reaction deficits in sperm from men with varicocele are related to the transition metal content of their semen.


METHODS
Cadmium and zinc in semen and blood plasma were assayed for fertile males, men without varicocele who required intracytoplasmic sperm injection to achieve fertilization, and men evaluated for potential varicocele-associated infertility. The relationship between actin cytoskeletal distributions and acrosome status was determined for fertile donor sperm in the presence and absence of exogenous cadmium.


METHODS
University hospital-based molecular biology research laboratory.


METHODS
Patients from two university hospital-based IVF-assisted reproductive technology programs and two male urology private practices.


METHODS
Fertile donor sperm were exposed to exogenous cadmium during capacitating incubations followed by culture at temperatures up to 41 degrees C.


METHODS
Metal ion levels in semen and blood plasma were determined by graphite furnace atomic absorption spectroscopy. Motile sperm were examined for mannose ligand binding and the ability to undergo spontaneous and induced acrosome reactions. Unfixed, Triton-permeabilized sperm were probed with antiactin and antimyosin antibodies.


RESULTS
Cadmium was elevated and zinc was decreased in the seminal plasma of men with varicocele. The content of these metals in semen and blood was not correlated. Cadmium exposure in vitro reduced mannose receptor expression, acrosome exocytosis, and cytoskeletal formation by fertile donor sperm.


CONCLUSIONS
Defects in transition metal regulation or excessive cadmium exposure are involved in varicocele-associated infertility.
Benoff
S
S
North Shore University Hospital, Boas-Marks Biomedical Science Research Center, New York 11030, USA.
Hurley
I R
IR
Barcia
M
M
Mandel
F S
FS
Cooper
G W
GW
Hershlag
A
A
D000177:Acrosome / Q000502:physiology; D000199:Actins / Q000378:metabolism; D001769:Blood / Q000378:metabolism; D002104:Cadmium / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D003599:Cytoskeleton / Q000187:drug effects / Q000502:physiology; D005089:Exocytosis / Q000187:drug effects; D006801:Humans; D007248:Infertility, Male / Q000209:etiology* / Q000378:metabolism / Q000503:physiopathology; D037181:Lectins, C-Type; D008297:Male; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins; D011956:Receptors, Cell Surface / Q000378:metabolism; D012661:Semen / Q000378:metabolism; D013696:Temperature; D014646:Varicocele / Q000150:complications* / Q000378:metabolism; D015032:Zinc / Q000378:metabolism
D000199:Actins; D037181:Lectins, C-Type; D000090323:Mannose Receptor; D037241:Mannose-Binding Lectins; D011956:Receptors, Cell Surface; D002104:Cadmium; D015032:Zinc