Abstract
Human β-endorphin produced a potent antinociceptive response as estimated by the tail-flick test in rats after intraventricular injection. On a molar basis, the peptide was 21 times more potent than morphine and in addition, the peptide produced morphine-like catatonia and hypothermia. These responses were blocked by naloxone. Repeated injections of the peptide induced tolerance to analgesic response, catatonia and hypothermia. Cross tolerance to morphine was also observed.
Original language | English (US) |
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Pages (from-to) | 390-396 |
Number of pages | 7 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 74 |
Issue number | 2 |
DOIs | |
State | Published - Jan 24 1977 |
Bibliographical note
Funding Information:by the National Institute of Drug (H.H.L.), and NIH Grant GM-2907 Institute of Mental Health Research