Cervical anatomy limits the use of transcervical intrauterine artificial insemination (TC AI) in sheep. We have developed an instrument to cope atraumatically with the cervix; although this instrument has not affected fertilization rate or pregnancy rate through Day 3, the effects on sperm transport and pregnancy after Day 3 are not known. The objective of the present study was to determine whe...

This book presents summaries by specialists of subjects related directly or indirectly to conception. The first five papers deal with male and female germ cells-their production, protection, release, and early transport. Chapters follow on fertilization, transportation of the zygote, and implantation. Finally there is consideration of immunological phenomena relating to fertility and fertility ...

Background: Spermatozoa are able to sense an attractant molecule gradient and as a consequence, orient their movement towards the source of the attractant. This mechanism is known as sperm chemotaxis. In recent years, our laboratory contributed to the knowledge of several features of mammalian sperm chemotaxis. These include the size and physiological state of the chemotactic sperm population, ...

Introduction Recently, a new procedure for intrauterine insemination (IUI) in sows has been established (1,2). The procedure consists of a specially designed catheter that can be passed through the cervix allowing the deposition of sperm in the uterus. Using this technique, the number of spermatozoa per dose can be reduced by up to 1 billion spermatozoa. It has been demonstrated that the IUI te...

Dyneins are high molecular weight ATPases that function as microtubule-based molecular motors. The axonemal dyneins, discovered 30 years ago, are responsible for the beating movement of cilia and sperm flagella, which they generate by producing sliding between adjacent microtubules. Cytoplasmic dynein, more recently discovered, is involved in diverse activities, including intracellular transpor...

BACKGROUND Voltage-dependent anion channel (VDAC), a channel protein, exists in the outer mitochondrial membrane of somatic cells and is involved in multiple physiological and pathophysiological processes. Up until now, little has been known about VDAC in male germ cells. In the present study, the relationship between VDAC and human sperm motility was explored. METHODS Highly motile human spe...

Therapeutic targets for male contraception are associated with numerous problems due to their focus on disrupting spermatogenesis or hormonal mechanisms to produce dysfunctional sperm. Here we describe the dual genetic deletion of α1A-adrenergic G protein-coupled receptors (adrenoceptors) and P2X1-purinoceptor ligand gated ion channels in male mice, thereby blocking sympathetically mediated spe...

Innexins are the subunits of invertebrate gap junctions. Here we show that the innexin INX-14 promotes sperm guidance to the fertilization site in the Caenorhabditis elegans hermaphrodite reproductive tract. inx-14 loss causes cell nonautonomous defects in sperm migration velocity and directional velocity. Results from genetic and immunocytochemical analyses provide strong evidence that INX-14 ...

Most combination OCPs contain ethinyl estradiol (20 to 50 mcg) and a synthetic progestin (e.g., norgestrel, norethindrone, levonorgestrel, desogestrel). These pills inhibit ovulation in most women. They also induce thickening of the cervical mucus, which impedes transport of sperm to the uterus. With perfect use, only 0.1 percent of women become pregnant within the first year of using a combina...