03-04-2006, 05:43 PM
please someome could explain this!
that means that serum bicarbonate is decreased!?and the sperm acount is normal!?
Over the past decade the fundamental biochemical defect in CF has been identified. The gene has been cloned and up to 300 alleles have been discovered. The gene product is a protein called the cystic fibrosis transmembrane conductance regulator. This regulator, the main chloride transport system, is defective in individuals with CF. The regulator is synthesized within the epithelial cell, then transported to the apical cell membrane of the epithelial duct cells of the proximal pancreatic duct. Its main function is to act as a chloride channel activated through cAMP-mediated phosphorylation, thus allowing secretion of chloride ions into the pancreatic duct or to the outside of the body. In addition to cystic fibrosis transmembrane conductance regulator, these cells contain "Cl-/HCO3- exchangers," which are responsible for bicarbonate secretion and are dependent on luminal chloride, which is supplied by cAMP-activated chloride channels. Thus, in CF, altered chloride secretion results in decreased bicarbonate production and ultimately failure to adequately hydrate and alkalinize the concentrated protein secretions of the acinar cells. This proteinaceous material becomes inspissated, resulting in ductal obstruction and ultimately acinar cell destruction, fibrosis and mal-absorption. The decrease in bicarbonate secretion also results in failure to neutralize duodenal acid, thus leading to further malabsorption by decreasing lipase activity and altering the bioavailability of enteric-coated enzyme supplement.
http://gastroresource.com/gitextbook/en/...2-8-pr.htm
Why is CF associated with infertility?
Genetic changes in the CF gene can cause a variety of complications, ranging from no symptoms at all to the classic symptoms of CF. In the middle falls a range of medical concerns including chronic respiratory infections, pancreatic insufficiency, and male infertility.
Genetic changes in the CF gene can cause infertility in men. They cause a condition called CBAVD, or congenital bilateral absence of the vas deferens. Almost all men with CF have CBAVD and therefore experience infertility
What is CBAVD?
CBAVD (congenital bilateral absence of the vas deferens) refers to the improper development of the tube through which sperm are released from the testes. CBAVD is present at birth, but most men do not become aware of it until they have difficulty with fertility.
Having CBAVD is like being born with a vasectomy: you have sperm, but the pathway to release them is missing.
What can I do if I have CF-related CBAVD?
Men with CBAVD have a number of options to help them conceive with their partners. Since they have functional sperm but have a block in the pathway that releases the sperm, family planning options that use their sperm rely on assisted reproductive technology (ART).
ICSI (intracytoplasmic sperm injection) is an option that is currently available. It is important to realize that these involve going to a fertility specialist or IVF (in vitro fertilization) clinic.
http://www.dnadirect.com/resource/condit...tility.jsp
that means that serum bicarbonate is decreased!?and the sperm acount is normal!?
Over the past decade the fundamental biochemical defect in CF has been identified. The gene has been cloned and up to 300 alleles have been discovered. The gene product is a protein called the cystic fibrosis transmembrane conductance regulator. This regulator, the main chloride transport system, is defective in individuals with CF. The regulator is synthesized within the epithelial cell, then transported to the apical cell membrane of the epithelial duct cells of the proximal pancreatic duct. Its main function is to act as a chloride channel activated through cAMP-mediated phosphorylation, thus allowing secretion of chloride ions into the pancreatic duct or to the outside of the body. In addition to cystic fibrosis transmembrane conductance regulator, these cells contain "Cl-/HCO3- exchangers," which are responsible for bicarbonate secretion and are dependent on luminal chloride, which is supplied by cAMP-activated chloride channels. Thus, in CF, altered chloride secretion results in decreased bicarbonate production and ultimately failure to adequately hydrate and alkalinize the concentrated protein secretions of the acinar cells. This proteinaceous material becomes inspissated, resulting in ductal obstruction and ultimately acinar cell destruction, fibrosis and mal-absorption. The decrease in bicarbonate secretion also results in failure to neutralize duodenal acid, thus leading to further malabsorption by decreasing lipase activity and altering the bioavailability of enteric-coated enzyme supplement.
http://gastroresource.com/gitextbook/en/...2-8-pr.htm
Why is CF associated with infertility?
Genetic changes in the CF gene can cause a variety of complications, ranging from no symptoms at all to the classic symptoms of CF. In the middle falls a range of medical concerns including chronic respiratory infections, pancreatic insufficiency, and male infertility.
Genetic changes in the CF gene can cause infertility in men. They cause a condition called CBAVD, or congenital bilateral absence of the vas deferens. Almost all men with CF have CBAVD and therefore experience infertility
What is CBAVD?
CBAVD (congenital bilateral absence of the vas deferens) refers to the improper development of the tube through which sperm are released from the testes. CBAVD is present at birth, but most men do not become aware of it until they have difficulty with fertility.
Having CBAVD is like being born with a vasectomy: you have sperm, but the pathway to release them is missing.
What can I do if I have CF-related CBAVD?
Men with CBAVD have a number of options to help them conceive with their partners. Since they have functional sperm but have a block in the pathway that releases the sperm, family planning options that use their sperm rely on assisted reproductive technology (ART).
ICSI (intracytoplasmic sperm injection) is an option that is currently available. It is important to realize that these involve going to a fertility specialist or IVF (in vitro fertilization) clinic.
http://www.dnadirect.com/resource/condit...tility.jsp