Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new male contraception method is undergoing clinical trials in India. The goal of this research is to achieve a method which restricts its effects to the region of the vas deferens. First, the belief that there was a strong peristaltic movement in the vas during ejaculation had to be examined. It was found that only the ampula part of the vas is given a tight squeeze to release the stored sperm into the semen. Therefore, a device to manipulate sperm could safely be inserted into the vas. Using the fact that the acrosomal membrane of the sperm is disturbed when sperm are subjected to electrical currents, Dr. S. K. Guha, of the Indian Institute of Technology in New Delhi, decided to try to generate a current inside the vas to disturb the acrosomal membranes. Since styrene maleic anhydride (SMA) hydrolyses when mixed with body fluids, it creates a slight charge. After injecting SMA into the vas, the electrical balance of the sperm which passes it is disturbed, causing the acrosomal membrane to shrink and rupture, letting water enter the sperm. When the sperm head bursts, the enzymes acrocin and hyaluronidase are released. Without these enzymes, the sperm can not penetrate the ovum and fertility control is achieved. This procedure can be reversed by injecting a solvent to dissolve the SMA in the scrotal sac. Phase I clinical studies began in 1989, and the next Phases should begin soon. The advantages of this method include the fact that no surgical procedure is required, sperm production is not actually blocked so there is no rise in anti-sperm antibody titres, and the contraceptive action can last as long as 10 years. Dr. Guha cautions, however, that education of the people will ultimately play a more important role in population control in India than the availability of a variety of contraceptive methods.
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PMID:Charging the vas deferens -- a novel male contraceptive method. 1217 80