[The hyper- and hypoalgesic effects of human and animal blood serum proteins]. / Giper- i gipoalgeticheskie éffekty belkov syvorotki krovi cheloveka i zhivotnykh.

The protein fractions precipitated by ammonium sulfate from the bovine, human and Greenland's seal blood sera enhanced the pain sensitivity of mice, rats and rabbits. The proteins fraction of the seal blood serum was divided in six subfractions by ion-exchange chromatography. One of these subfractions clearly showed hyperalgesic properties, while the others had an opposite effect. The collagenase hydrolysate of the same protein fraction had an analgetic activity. The results of this and previous studies suggest the occurrence of one more nociception-regulating protein-peptide system in mammals.

[The effect of blood serum proteins from the seal on the analgetic action of narcotic analgesics]. / Vliianie belkov syvorotki krovi tiulenia na boleutoliaiushchee deistvie narkoticheskikh anal'getikov.

The protein fraction isolated from blood of seal, Phoca groenlandica, has been found to produce hyperalgesic effect on rats exposed to thermic or electrocutaneous nociceptive stimulation, but fail to affect writhes provoked by intraperitoneal injection of acetic acid solution on mice. When combined with morphine, the fraction lowered completely its narcotic analgetic action in the above mentioned tests. On the contrary, these same proteins combined with promedol or fentanil enhanced and prolonged analgetic effect of the latter. Tested in vitro the protein showed neither opioid nor anti-opioid activity. Therefore it is reasonable to suppose that neurophysiological activity of the isolated fraction is due to the peptides formed on enzymatic hydrolysis of proteins in vivo rather than these proteins as such.