Related Experiment Video
Updated: Aug 15, 2026
In Vivo SiRNA Transfection and Gene Knockdown in Spinal Cord via Rapid Noninvasive Lumbar Intrathecal Injections in Mice
Published on: March 22, 2014
Release of [Met5]enkephalin from the spinal cord by intraventricularly administered endomorphin-2, but not
M Ohsawa1, M Shiraki, H Mizoguchi
1Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
Abstract:
Effects of intraventricular injection of endomorphin-1, endomorphin-2 and beta-endorphin on the release of immunoreactive [Met(5)]enkephalin from the spinal cord were studied in pentobarbital anesthetized rats. Intraventricular injection of endomorphin-2, but not endomorphin-1, caused an increased release of immunoreactive [Met(5)]enkephalin in the spinal perfusates. Beta-endorphin given intraventricularly also increased the release of immunoreactive [Met(5)]enkephalin in an amount 15-fold higher than that produced by endomorphin-2. The increase of the release of immunoreactive [Met(5)]enkephalin induced by endomorphin-2 was blocked by mu-opioid receptor antagonist CTOP. Our result suggests that endomorphin-2 stimulates another subtype of mu-opioid receptor different from that acted by endomorphin-1 at the supraspinal site and subsequently increases the release of [Met(5)]enkephalin from the spinal cord.
