AJP - Regulatory, Integrative and Comparative Physiology, Vol 239, Issue 3 332-R336, Copyright © 1980 by American Physiological Society
In vivo recording of oviductal contractions in rabbits during the periovulatory period
R. J. Bourdage and S. A. Halbert
Muscular activity of the oviductal isthmus was recorded in intact awake
rabbits with an extraluminal optoelectronic transducer. Telemetered data
were collected continuously during the periovulatory period to relate
changes in contraction frequency to oviductal transport function. Mean
frequencies during estrus ranged from 11.7 to 18.7 contractions/min.
Animals stimulated to ovulate either by luteinizing hormone (LH) or by
mating showed equivalent responses. Within 2 h following the stimulus, the
frequency increased rapidly and remained elevated more than 50% above the
estrous control level for approximately 10 h. Thereafter, the frequency
declined slowly to reach a second plateau, 30% below the control level,
which was maintained throughout the 2nd and 3rd poststimulus days.
Subsequently, the activity returned to the prestimulus level. The periods
of elevated and depressed activity correspond closely in time to the
periods of rapid preovulatory transport of sperm and slow postovulatory
transport of ova through the isthmus, suggesting the possibility of
regulation of gamete transport by the oviductal musculature.
