Dynamics of Bovine Sperm Interaction with Epithelium Differ Between Oviductal Isthmus and Ampulla.
In mammals, many sperm that reach the oviduct are held in a reservoir by binding to epithelium. To leave the reservoir, sperm detach from the epithelium; however, they may bind and detach again as they ascend into the ampulla toward oocytes. In order to elucidate the nature of binding interactions along the oviduct, we compared the effects of bursts of strong fluid flow (as would be caused by oviductal contractions), heparin, and hyperactivation on detachment of bovine sperm bound in vitro to epithelium on intact folds of isthmic and ampullar mucosa. Intact folds of oviductal mucosa were used to represent the strong attachments of epithelial cells to each other and to underlying connective tissue that exist in vivo. Effects of heparin on binding were tested because heparin binds to the Binder of SPerm (BSP) proteins that attach sperm to oviductal epithelium. Sperm bound by their heads to beating cilia on both isthmic and ampullar epithelia and could not be detached by strong bursts of fluid flow. Addition of heparin immediately detached sperm from isthmic epithelium but not ampullar epithelium. Addition of 4-aminopyridine immediately stimulated hyperactivation of sperm but did not detach them from isthmic or ampullar epithelium unless added with heparin. These observations indicate that the nature of binding of sperm to ampullar epithelium differs from that of binding to isthmic epithelium; specifically, sperm bound to isthmic epithelium can be detached by heparin alone, while sperm bound to ampullar epithelium requires both heparin and hyperactivation to detach from the epithelium.
Department of Biomedical Sciences, Cornell University, Ithaca, New York.
Florencia
F
Ardon
Department of Biomedical Sciences, Cornell University, Ithaca, New York.
Ross D
RD
Markello
Department of Biomedical Sciences, Cornell University, Ithaca, New York Family Planning Research Institute, Huazhong University of Science and Technology, Wuhan, China.
Lian
L
Hu
Department of Biomedical Sciences, Cornell University, Ithaca, New York.
Zarah I
ZI
Deutsch
Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York.
Chih-Kuan
CK
Tung
Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York.
Mingming
M
Wu
Department of Biomedical Sciences, Cornell University, Ithaca, New York sss7@cornell.edu.
Susan S
SS
Suarez
D015761:4-Aminopyridine / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D004848:Epithelium / Q000033:anatomy & histology / Q000502:physiology; D005187:Fallopian Tubes / Q000033:anatomy & histology / Q000502:physiology*; D005260:Female; D006493:Heparin / Q000494:pharmacology; D057446:Hydrodynamics; D008297:Male; D029589:Seminal Plasma Proteins / Q000502:physiology; D013081:Sperm Motility / Q000187:drug effects / Q000502:physiology; D013094:Spermatozoa / Q000187:drug effects / Q000502:physiology*
D029589:Seminal Plasma Proteins; C425042:spermadhesin; D006493:Heparin; D015761:4-Aminopyridine
fallopian tube; fertilization; heparin; oviduct; spermatozoa