Effect of Adrenalectomy on Poliocidal Property of Serum of Normal Cebus and Convalescent Rhesus Monkeys. ∗

In preliminary experiments it was reported that the natural poliocidal property of the serum of one Nicaraguan Cebus monkey was lost after subjecting the animal to bilateral adrenalectomy. 1 It was also demonstrated that this property could be restored by the addition of a small amount of cortical hormone, but not of adrenaline, to the deficient serum. In order to lend significance to this isolated observation it became necessary to repeat these experiments on a larger scale. Furthermore, it seemed of interest to extend the scope of this work to an investigation of the effect of adrenalectomy on the virucidal property of the serum of rhesus monkeys which had recovered from a paralyzing attack of poliomyelitis.

In conducting these experiments it was soon discovered that there exists a fundamental difference between black-faced Cebus monkeys from South America and white-faced Cebus monkeys from Central America with respect to the presence of natural poliocidal substances in their serum. Thus, in keeping with previous experience, 2 the normal serum of 3 Nicaraguan Cebus monkeys produced either complete or partial neutralization of poliomyelitis virus in vitro, 2 monkeys receiving the serum-virus mixtures intracerebrally remaining entirely free from symptoms, while the 3rd animal developed partial paralysis on the 17th day. On the other hand, the normal serum of 3 Brazilian Cebus monkeys gave no evidence whatsoever of being capable of inactivating the virus in vitro. Three control monkeys receiving the same amount of virus, i. e., 0.2 cc. 10% virus suspension, mixed with 0.8 cc. saline accompanied these tests. All developed complete paralysis within from 7-9 days.

After having demonstrated the presence of natural poliocidal substances in the serum of 3 Nicaraguan Cebus monkeys, these animals were subjected to bilateral adrenalectomy. The adrenals were exposed by a paravertebral incision, with the last rib as the upper landmark, the vessels were ligated, and both glands removed in toto in one stage.