[New findings concerning the coronaroactive proteins of the hypothalamus].

Our previous studies have shown that the two coronarodilatatory hypothalamic proteins isolated by us are not only carriers for neurohormones "K" and "C" but also procursors of coronarodilatory substances. In the present study we have looked at some physico-chemical properties of these proteins through isoelectric focusing and gel electrophoresis as well as the possibility of obtaining coronaroactive fragments by proteolytic enzymes. The results obtained have shown that the isoelectric points of the coronaroactive proteins are between pH 6.2 and 6.4. Polyacrylamide gel-electrophoresis has shown that one of the coronaroactive proteins, the carrier of neurohormone "C", moves towards the anode and is homogenous while carrier of neurohormone "K" is made up of two protein fractions. Under the action of certain enzymes (trypsin and pepsin) two coronaroactive fragments are obtained from the "neutral" protein carrier. Such an effect is not observed following the action of pronase and chymotrypsin. The physico-chemical properties of these fragments require further studies.