ABSTRACT
Head plasma membranes were isolated from the sperm-rich fraction of boar semen and from sperm-rich semen that had been subjected to three commercial preservation processes: Extended for fresh insemination (extended), prepared for freezing but not frozen (cooled), and stored frozen for 3-5 weeks (frozen-thawed). Fluorescence polarization was used to determine fluidity of the membranes of all samples for 160 min at 25 degrees C and also for membranes from the sperm-rich and extended semen during cooling and reheating (25 to 5 to 40 degrees C, 0.4 degrees C/min). Head plasma membranes from extended semen were initially more fluid than from other sources (P less than 0.05). Fluidity of head membranes from all sources decreased at 25 degrees C, but the rate of decrease was significantly lower for membranes from cooled and lower again for membranes from frozen-thawed semen. Cooling to 5 degrees C reduced the rate of fluidity change for plasma membranes from the sperm-rich fraction, while heating over 30 degrees C caused a significantly greater decrease. The presence of Ca++ (10 mM) lowered the fluidity of the head plasma membranes from sperm-rich and extended semen over time at 25 degrees C but did not affect the membranes from the cooled or frozen-thawed semen. The change in head plasma membrane fluidity at 25 degrees C may reflect the dynamic nature of spermatozoa membranes prior to fertilization. Extenders, preservation processes and temperature changes have a strong influence on head plasma membrane fluidity and therefore the molecular organization of this membrane.
Subject(s)
Preservation, Biological , Sperm Head/cytology , Spermatozoa/cytology , Animals , Calcium/pharmacology , Cell Membrane/drug effects , Cell Membrane/physiology , Fluorescence Polarization , Male , Molecular Structure , Sperm Head/drug effects , Swine , Temperature , Time Factors , ViscosityABSTRACT
The interaction between human spermatozoa and cervical mucus was studied during 14 cycles of artificial insemination (AI) with a cervical cup. The concentration of spermatozoa in the inseminate was determined as were the percentage of motility, mean swimming speed, and sperm morphology. The percentage of motility, swimming speed, and morphology of spermatozoa in the mucus were determined at 1 hour and 48 hours after AI. The percentage of motile sperm was always higher in the cervical mucus than in the semen. In some cases, spermatozoa appeared to swim faster in the mucus than in the semen but in other cases the reverse was true. In all 14 cases some spermatozoa could be found in the mucus at 48 hours after AI. In general, the percentage of motility and swimming speeds of the cervical sperm remained unchanged over the 48-hour study interval. The percentage of spermatozoa with normal morphology was higher in the cervical mucus than in the semen. The alteration in the composition of the sperm population appeared to result from exclusion by the mucus of most classes of abnormal sperm. The morphology of the cervical sperm population was similar at 1 hour and at 48 hours after AI.
PIP: The interaction between human spermatozoa and cervical mucus was studied during 14 cycles of (AI) artificial insemination with a cervical cup. The concentration of spermatozoa in the inseminate was determined as were the % of motility, mean swimming speed, and sperm morphology. The % of motility, swimming speed, and morphology of spermatozoa in the mucus were determined at 1 hour and 48 hours after AI. The % of motile sperm was always higher in the cervical mucus than in the semen. In some cases, spermatozoa appeared to swim faster in the mucus than in the semen but in other cases the reverse was true. In all 14 cases some spermatozoa could be found in the mucus at 48 hours after AI. In general, the % of motility and swimming speeds of the cervical sperm remained unchanged over the 48-hour study interval. The % of spermatozoa with normal morphology was higher in the cervical mucus than in the semen. This alteration in the composition of the sperm population appeared to result from exclusion by the mucus of most classes of abnormal sperm. The morphology of the cervical sperm population was similar at 1 hour and at 48 hours after AI.
Subject(s)
Cervix Mucus/physiology , Fertilization , Spermatozoa/physiology , Female , Humans , Insemination, Artificial , Male , Pregnancy , Semen/physiology , Sperm Head/cytology , Sperm Motility , Sperm Tail/cytology , Spermatozoa/cytologyABSTRACT
When flat sperm heads that have been stained to fluorescence are examined in a flow cytometer, unexpectedly, skewed pulse height distributions are obtained despite the apparent homogeneity of the samples. This anomaly has been ascribed to an optical artifact that arises when the cells are oriented in flow. We have extended our model for fluorescent scattering to spheroids and here explore some aspects for oblate spheroids which serve to model sperm heads. Although computational limitations have restricted these studies to oblate spheroids about 1.5 micrometer in diameter and an eccentricity of 0.1, the results clearly show effects of particle size, shape, optical properties and particularly of orientation on the differential scattering cross-sections. This plethora of information contained in the fluorescent signals may suggest further experiments.
