Epididymis: where sperm get fine tuned and functional
June 8, 2012Carole 3 Comments »In honor of the up-coming Father’s Day, I thought I’d tell the story of a little known but highly significant male reproductive organ- the epididymis. It is pronounced Eppie-Diddy-Mus which may sound like an urban rapper but I assure you, it is not. The epididymis which is attached to and lies just above the testicle, is responsible for the “detailing” or “fine-tuning” of freshly made sperm just released from the testicle. Yes, the testicle produces the sperm but without the polishing and detailing in the epididymis, sperm wouldn’t swim and wouldn’t be able to fertilize an egg. So pretty important, no?
It is important for a male to be able to tell when there are changes in the size or feel of his testicles or epididymides because these may be signs of cancer or inflammation associated with infection. This link, Get to Know Your Testis, explains how to find the epididymis ( which lies to the top and back of each testicle). You should also be able to also feel the tubes leaving from the epididymis called the vas deferens. If a vasectomy is performed, these tubes which normally carry sperm from the epididymis to the penis are clipped inside the scrotum to render the male sterile. Reconnecting the tubes surgically via a vasectomy-reversal procedure can restore fertility if not too much time has elapsed between the two surgeries. There are two kinds of vasectomy reversal procedures as described in this article from the NY TImes Health Guide. It’s worth reading for those who want to know more about vasectomy and it’s reversal.
- Vasovasostomy . The severed ends of the vas deferens are sewn back together.
- Vasoepididymostomy . The vas deferens is surgically reattached directly to the epididymis. This procedure is more difficult to perform and is used when vasovasostomy cannot be performed or does not work.
But this post is about the epididymis, which despite years of research over many decades is still shrouded in mystery. The epididymis has three functionally distinct regions , the caput (or head), the corpus (or body) and the cauda (or tail). What is clear is that by the time the sperm transits these three regions and is stored in the final region, the cauda, prior to ejaculation, it is a fully mature sperm, capable of strong forward progressive motility and has acquired the molecular ability to fertilize the egg. But in spite of decades of research in both animals and humans, we still don’t fully understand all the molecular changes that occur in the sperm membrane within this organ.
The review article New Insights into Epididymal Biology and Function is a highly detailed review for those who want to understand the nitty-gritty scientific efforts to understand the molecular mechanisms responsible for the epididymides’ unique ability to grant life-giving properties to sperm. For the andrologist or reproductive scientist, it has lots of references for further study.
Up to 40% of infertility is due to male-specific causes. Some of these causes are not obvious and may well be due to molecular sperm defects we are incapable of detecting–and may be due to faulty “fine-tuning” of sperm cells in the epididymis. Much of male-specific infertility can be addressed by the use of intracytoplasmic sperm injection or ICSI, which bypasses some deficiencies in sperm functionality acquired in the epididymis, like the inability to swim. However, ICSI is not without risks and sometimes fertilization fails even with ICSI so ICSI is not the solution for every cause of male infertility.
The original sperm cell produced by the testis looks like a sperm cell, but it is non-functional and can not swim. That is why testicular sperm can only be used with ICSI, not for conventional IVF or insemination, because it can not yet swim, nor fertilize an egg. The lipid (fat molecules) and proteins that are inserted into the plasma membrane of the sperm cell also change while in transit through the epididymis. Some molecules are shedded and others are added to the sperm membrane to ultimately produce a functional sperm cell which can swim to, attach to, penetrate and fertilize an egg.
Researchers looking for male contraceptives are also interested in understanding which proteins are involved with functional maturation of sperm so that a reversible non-hormonal method to block sperm maturation can be designed. Likewise, if the molecular maturation mechanisms were understood, it might be possible to mature sperm in vitro and be able to use conventional in vitro fertilization, instead of ICSI, to gain the benefit of some natural selection. Therefore, a better understanding of the epididymis may lead to new therapies for infertility as well as new methods for contraception.
Each segment of the epididymis appears to have distinct gene profiles, producing a highly regulated cellular micro-environment, capable of responding to signalling pathways in a highly orchestrated way. Each segment is physiologically separated from the adjacent segment by connective tissue, permitting compartmentalization of the organ and segment-specific regulation . Not surprisingly, the various cells of the epididymis respond to androgens, the male hormone. Studies suggest that sperm and the cells lining the epididymis also exchange cell to cell signals as part of the in transit maturation process and probably further regulate that process. The epididymis may have the most complex fluid composition of any exocrine gland and this composition varies with each region of epididymis. The caput produces 70-80% of the proteins secreted into the epididymal lumen. By the time the sperm get to the cauda end, most of the fluid has been reabsorbed, fundamentally increasing the concentration of proteins bathing the sperm in the tubes.
Take good care of your epididymis and it will take good care of you. Check your epididymis (and testicles) every month for changes in size, areas of hardening or changes in sensitivity or pain. Let your physician know about any unusual changes which could indicate epididymal (or testicular) inflammation, infection, presence of cysts or nodules, or even cancer, all of which can impair your fertility and overall health. Here’s a link to more information on how to do a self-exam.
Happy Father’s Day!
P.S. This post was written as part of Lori Shandle-Fox’s (“Laughing-is-Conceivable” Blogger), Bounce-Around Posts. See all the Bounce Around Father’s Day posts below.
Blog #1 “Laughing IS Conceivable”
Blogger: Okay, this is me, Lori Shandle-Fox
I’m a former stand-up comic & infertility survivor.
Post: “It’s All in the Wrist aka I Know What YOU Just Did”
This post is an excerpt from my new ebook: Laughing IS Conceivable: One Woman’s Extremely Funny Peek into the Extremely Unfunny World of Infertility.
This post emphasizes the husband’s part in this whole sordid infertility treatment business.
Post Link: http://laughingisconceivable.
Blog #2: “Parenthood For Me”
Blogger: Erica Walther Schlaefer, Rochester NY area, USA
Erica is President and Founder of Parenthood For Me- a non-profit organization whose mission is to provide financial and emotional support to those building families through adoption or medical intervention.
Post: This post was written by a man named “Sam”. He discusses his bout with infertility and how he and his wife finally got their child.
Link: http://parenthoodforme.
Blog #3: Baby Manifest-O
Blogger: Helen Adrienne, New York, USA
Licensed Certified Social Worker and certified hypnotherapist- Also a general therapist who specializes in infertility counseling, couples counseling for infertility, mind/body stress reduction for infertility and gynecological and reproductive issues.
Post: “News Men Can Use”
Helen discusses how something from a man’s past may be still hurting him today… and affecting how he deals with the whole “infertile couple” issue.
Post Link:Post: http://mind-body-unity.com/
Blog#4 Fertility Lab Insider
Blogger: Carole Wegner Ph.D, North Carolina, USA
Post: Sure, we can gab all day about infertility and men. But now we’re going to hear from a scientist. In this post, Carole discusses an important part of the male reproductive system that you may not even be aware of. (I definitely wasn’t)
Post Link: http://fertilitylabinsider.
Blog#5 “A Childless World”
Blogger: Hans Morse, Sydney Australia
Hans Morse has had a varied career and after 7 years working as an Australian Federal Police Officer and other protection agency roles, Hans moved to a career in sales & marketing.
Post: Okay, I’m cheating here a little. Hans isn’t really a blogger but he did write an entire book about his experiences of going through infertility with his wife, Corinne. And on his site, he offers some good man-to-man advice for husbands as well as friends.
Post Link: http://achildlessworld.com/6.
Blog#6: Fertility Wellness Group
Bloggers: Diana Palmentiero & Lenore C. Pranzo, Connecticut, USA
Diana Palmentiero helps other women who are having fertility issues just as she did with both of her children. She has experience with secondary infertility, acupuncture, meditation, qi-gong and pre and post natal yoga. She is also a Certified Wellness Coach.
Lenore C. Pranzo is a marriage and therapist therapist with a background in substance abuse, mental health and adolescent counseling. She has a Masters degree from Fairfield University in Marriage and Family Therapy. Due to her difficulty getting pregnant she utilized western medicine and eastern medicine (including acupuncture) to conceive her twins.
Post: “At Father’s Day, What About the Men?”
In this post, Diana looks back at her own childless Father’s Day to remind us not to forget about the husbands. Lenore gives some great advice to the men on how to help their wives through their infertility struggles in order to become better partners.
Blog#7: “Secret Infertility Hope”
Blogger: Fran Meadows, Greater NYC area, USA
Fran is an Infertility Advocate at RESOLVE: The National Infertility Association and Author of The Truth Behind The Secret “Infertility”
Post: “Father’s Day for All…No Exclusions”
This post is for men… but there are some important notes for the women who live with and love them also.
Post Link: http://www.secretinfertility.
Blog#8: Thierry-health.com
Blogger: Thierry Clerc, Cambridge, United Kingdom
Thierry is a homeopath and nutritional consultant. He is fully registered for the practice of homeopathy, biofeedback analysis, and therapies based on herbs, nutrition and life-style.
Post: “Why ‘Will-be Daddy’ Needs to Take Care of His Health As Well”
Thierry gives insight into the increasing problems of male infertility and also provides an informative link to an article that breaks it all down.
Post Link: http://www.thierry-health.com/
Blog#9 ETCM Fertility
Blogger: Jane Johnson, Fertility Therapist, United Kingdom
Jane is a professional acupuncturist and herbalist as well as an accomplished Yoga therapist who specialises in Fertility issues and women’s health.
Post: “Infertility: Men, 10 Times Easier to Treat?”
Jane discusses in this post, why male infertility patients are easier for acupuncturists to treat than female…if you can get them to make an appointment that is.
Post Link: http://etcm.co.uk/blog/?p=430
Blog#10: Baptism By Fire
Blogger: Jules Wolfers, Louisville, KY, USA
Jules’ blog is about how she deals with infertility and childlessness.
Post: “The Children of Men”
Jules talks with a male friend who “came out” to her about his own infertility in this incredible insight into what a man goes through.
Post Link: http://gameguessing.blogspot.
© 2012, Carole. All rights reserved.
June 11th, 2012 at 2:58 am
[...] Blog#4 Fertility Lab Insider [...]
June 15th, 2012 at 6:23 pm
[...] Day means to them and to the men in their lives. Bloggers share different perspectives— Fertility Lab Insider blog discusses epididymis, “a little known but highly significant male reproductive organ,” [...]
November 14th, 2012 at 8:33 am
[...] Male infertility due to CBAVD is “treated” by recovering sperm surgically from either the testicles (TESE) or from the epididymis (MESE or PESA). Sperm recovered surgically is frequently either non-motile (can not swim) or only weakly motile. Sperm acquire full motility as they move through the various regions of the epididymis, the smaller storage/maturation organ that lies on top of the testicle. Sperm injection (ICSI) is necessary to fertilize the egg if TESE/MESE or PESA sperm are used. More about the epididymis can be found at this previous post. [...]