CRYOPRESERVATION OF RAT SPERMATOZOA

CRYOPRESERVATION OF SPERMATOZOA FROM RATS WITH UNIQUE CHARACTERISTICS THAT ARE IMPORTANT FOR BIOMEDICAL RESEARCH HAS MANY ADVANTAGES. TO DATE, HOWEVER, THERE IS NO ESTABLISHED PROCEDURE TO PERFORM THIS. THIS IS BECAUSE EPIDIDYMAL SPERMATOZOA HAVE TO BE USED IN RATS. ALSO, INCUBATION OF EPIDIDYMAL SPERMATOZOA WITH PROSTATOVESICULAR FLUID EXTRACT TO MIMIC THE EJACULATE'S SPERM IS ONE APPROACH. CRYOPRESERVED HUMAN SPERMATOZOA MAY HAVE REDUCED FERTILITY PROBABLY DUE TO GLYCEROL, WHICH IS THE CRYOPROTECTIVE AGENT USED. THEREFORE, NEW PROCEDURES USING DIFFERENT AGENTS SHOULD BE STUDIED. NATURALLY OCCURRING CRYOPROTECTANTS SUCHAS FRUCTOSE, TREHALOSE, AND PROLINE ALONG WITH MILK MAY ALSO AVOID THE DELETERIOUS EFFECT OF GLYCEROL AND, THEREFORE, NEED TO BE STUDIED. USING THIS HYPOTHESIS, A CRYOPRESERVATION PROCEDURE WILL BE DEVELOPED FOR THE COMMONEST STRAIN OF RATS, SPRAGUE DAWLEY. THIS PROTOCOL WILL BE INVESTIGATED FOR THREE DIFFERENT STRAINS OF RATS.