Abstract
A preclinical evaluation for reversal through a noninvasive approach following long-term
vas occlusion with styrene maleic anhydride (SMA) has been attempted in langur monkeys
at the level of semen parameters, sperm functional tests, semen biochemistry, histology
and ultrastructure of reproductive organs, hematology and serum clinical biochemistry
including antisperm antibodies (ASA), prostate-specific antigen (PSA) and testosterone.
Noninvasive reversal through palpation, percutaneous squeezing and electrical stimulation,
forced vibratory movements and suprapubic percussion in the inguinal segments and
per-rectal digital massage was attempted in seven langur monkeys after 540 days following
vas occlusion. The results revealed instant azoospermia reversal on the same day of
reversal with impaired sperm quality, which showed gradual improvement and normospermia
with normal motility and viability after 60���90 days of reversal. Sperm functional
tests, including ultrastructure of spermatozoa, indicative of sterility in the initial
ejaculations, reached normalcy after 90���120 days of reversal. The seminal plasma
biochemistry indicative of obstructive azoospermia regained a normal pattern after
90���120 days of reversal. The morphology of testes that showed focal degeneration
during 540 days of vas occlusion and that of vasa deferentia that showed exfoliation
of epithelial cells resumed to normal morphology comparable with control animals after
150 days of reversal. The morphology of the epididymis, seminal vesicle and prostate
did not show appreciable changes following vas occlusion and after noninvasive reversal
compared with those of control animals. Hematology, serum clinical chemistry, ASA,
PSA and testosterone fluctuated within control limits, indicating safety of the procedure
at the level of accessory reproductive organs. The results suggest that noninvasive
reversal is feasible even after long-term vas occlusion with SMA and is safe without
adverse side effects.
Keywords
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to ContraceptionAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Vasectomy.Andrologia. 2001; 33: 125-134
- Vasectomy ��� safety and reversibility.in: Rajalakshmi M. Griffin P.D. Male contraception: present and future. New Age International Ltd., New Delhi1999: 251-263
- Disappearance rate of spermatozoa from the ejaculate following vasectomy.Fertil. Steril. 1969; 20: 163-170
- Patient noncompliance after vasectomy.Fertil. Steril. 1997; 68: 552-555
- What's new with male sterilization: an update.Contemp. Ob/Gyn. 1998; 43: 41-64
Guha SK. Contraceptive for use by a male. US Patent 54880705, 1996.
- Vas deferens, a site of male contraception: an overview.Asian J. Androl. 2001; 3: 87-95
- Ultrastructural changes in the spermatozoa of langur monkeys, Presbytis entellus entellus, after vas occlusion with styrene maleic anhydride.Contraception. 1998; 57: 125-132
- Intravasal contraception with styrene maleic anhydride and its noninvasive reversal in langur monkeys (Presbytis entellus entellus).Contraception. 1998; 8: 119-128
Mishra PK. Contraceptive efficacy of styrene maleic anhydride (SMA) in the lumen of vas deferens and its reversal in langur monkeys, Presbytis entellus entellus Dufresne. PhD Thesis, University of Rajasthan, Jaipur, India, 1999.
- Repeated vas occlusion and non-invasive reversal with styrene maleic anhydride for male contraception in langur monkeys.Int. J. Androl. 2000; 23: 36-42
- Non-invasive reversible vas occlusion with styrene maleic anhydride: a possible alternative to vasectomy.in: Puri C.P. Van Look P.F.A. Sexual and reproductive health. New Age International Ltd., New Delhi2001: 249-268
- Status of spermatogenesis and of sperm parameters in langur monkeys following long term vas occlusion with styrene maleic anhydride (SMA).J. Androl. 2003; 24: 501-509
- Reproductive system of north Indian langur (Presbytis entellus entellus Dufresne).J. Morphol. 1971; 135: 99-130
- WHO laboratory manual for the examination of human semen and sperm���cervical mucus interaction. Cambridge University Press, New York1992
- WHO laboratory manual for the examination of human semen and sperm���cervical mucus interaction. Cambridge University Press, New York1999
- Assessment of mitochondrial activity of human spermatozoa: motility/viability in fertile/infertile men.Mol. Androl. 1991; 3: 243-250
- In vitro decondensation of sperm nuclear chromatin of human spermatozoa: assessing sperm fertilizing potential.Arch. Androl. 1991; 27: 43-50
- Standardized procedures in human semen analysis.Curr. Sci. 1995; 68: 353-362
- Development of an assay to assess functional integrity of human sperm membrane and its relationship to other semen characteristics.J. Reprod. Fertil. 1984; 70: 219-228
- The resazurin reduction test provides an assessment of sperm activity.Fertil. Steril. 1991; 56: 743-746
- Methods of enzymatic analysis. Academic Press, New York1965
- Studies on the estimation of glycerol, fructose and lactic acid with particular reference of semen.Aust. J. Exp. Biol. 1959; 37: 441-450
- Epididymal markers in human infertility.J. Androl. 1985; 9: 91-101
- Medical laboratory technology and clinical pathology.WB Saunders Co., London1969
- Standardizing a method for clinical haemoglobinometry.U. S. Armed Forces Med. J. 1954; 5: 693-703
- Routine use of ultramicro methods in the clinical laboratory.Am. J. Clin. Pathol. 1951; 21: 1153-1172
- What is the best pregnancy rate that may be expected from vasectomy reversal?.J. Urol. 1993; 149: 1469-1471
- Pregnancy after vasovasostomy for vasectomy reversal: a study of factors affecting long-term return of fertility in 282 patients followed for 10 years.Hum. Reprod. 1989; 4: 318-322
- Results of 1469 microsurgical vasectomy reversals by Vasovasostomy Study Group.J. Urol. 1991; 145: 505-511
- Andrology at the end of the twentieth century: from spermatology to male reproductive health.Int. J. Androl. 1997; 20: 129-131
- Some vasovasostomized men are characterized by low levels of P34H, an epididymal sperm protein.J. Androl. 1999; 20: 214-219
- Ultrastructure of langur monkey epididymides prior to and following vasectomy and vasovasostomy.Eur. J. Morphol. 2000; 38: 24-33
- Phase II of a clinical trial of a vas deferens injectable contraceptive for the male.Contraception. 1997; 56: 245-250
- Histology of the rat vas deferens after injection of a non-occlusive chemical contraceptive.J. Reprod. Fertil. 1981; 63: 539-542
- Reversibility with sodium biocarbonate of styrene maleic anhydride, an intravasal injectable contraceptive, in male rats.Contraception. 1998; 58: 227-231
- Ultrastructural changes in the vas deferens of langur monkeys Presbytis entellus entellus after vas occlusion with styrene maleic anhydride and after its reversal.Contraception. 1999; 59: 137-144
- Male reproductive function and semen.in: Springer Verlag, New York1981: 319-320
- Glycerylphosphocholine in selected forms of male infertility.Andrologia. 1986; 18: 171-174
- 1H nuclear magnetic resonance studies of human seminal plasma from fertile and infertile men.J. Reprod. Fertil. 1993; 97: 51-55
- Neutral alpha-glucosidase, a specific marker for epididymal secretion in seminal pathology.Contracept. Fertil. Sex. 1997; 25: 939-941
- Seminal plasma alpha-glucosidase activity and male infertility.Hum. Reprod. 1998; 13: 591-595
- l-carnitine levels in the seminal plasma of fertile and infertile men: correlation with sperm quality.Int. J. Fertil. Womens Med. 2000; 45: 236-240
- A proton NMR study of the effect of a new intravasal injectable male contraceptive RISUG on seminal plasma metabolites.Reproduction. 2001; 122: 431-436
Article info
Publication history
Accepted:
August 24,
2004
Received in revised form:
August 18,
2004
Received:
June 24,
2004
Identification
Copyright
© 2005 Elsevier Inc. Published by Elsevier Inc. All rights reserved.
