AJP - Regulatory, Integrative and Comparative Physiology, Vol 254, Issue 1 75-R77, Copyright © 1988 by American Physiological Society
Verapamil blockade of pressor and uterine responses to AVP-OT analogue, oxypressin
D. Gazis, G. Gonzalez and M. Mendlowitz
Department of Physiology and Biophysics, Mount Sinai School of Medicine of City University of New York, New York 10029.
The effects of the calcium channel blocker verapamil on simultaneously
recorded uterine and pressor responses to the equipotent (in eliciting
these responses) oxytocin-vasopressin analogue, oxypressin, were studied in
urethan-anesthetized and pentolinium- and indomethacin-treated rats during
injections and infusions of this analogue. Doses of verapamil that almost
completely blocked the pressor response to infused oxypressin had no effect
on a pressor response to injected oxypressin of equal magnitude. Larger
doses of verapamil blocked the pressor response to injected oxypressin
somewhat. Uterine responses were only marginally affected by these doses of
verapamil, and there was no significant difference between infusion and
injection or between estrus and diestrus.
