[Improvement of cardiac puncture in mice]

Cardiac puncture through the anterior thoracic aperture, which was originally reported by Frankeberg, was improved. The improved method involved the use of a restraining board instead of manual holding. A mouse anesthetized with ether was fixed in a dorsal position on the restraining board, and then a needle of 26G X 1/2 was inserted through the skin just in front of the anterior thoracic aperture, keeping the syringe parallel to the long axis of the animal. A blood volume of 0.6-0.9 ml could be obtained even by an inexperienced collector, and the blood collection was usually completed within 10-20 s. The potential for repeated blood collection of 0.4-0.6 ml was facilitated by use of the present method at intervals of 7 days or more.