Dopaminergic neuronal sprouting and behavioral recovery in hemi-parkinsonian rats after implantation of amnion cells.

Cells obtained from human, monkey, or rat term amnion membrane produce an activity which, in vitro, increases process outgrowth from rat sympathetic neurons and from dopaminergic neurons of the rat ventral mesencephalon. To determine if these cells could induce sprouting of dopaminergic nerve fibers in vivo, the substantia nigra of rats was lesioned unilaterally with 6-hydroxydopamine and live-rat-term amnion cells, or killed-rat-term amnion cells were implanted into the denervated striata. A control group of rats received saline injections into the denervated striata. Rats implanted with live amnion cells had a significant decrease in turning in response to amphetamine. The lesioned and implanted striata of live-amnion-cell-implanted rats contained significantly greater areas of tyrosine hydroxylase-immunoreactive fibers than the lesioned and implanted striatum of rats in the killed-amnion-cell or saline groups. Differences in the area of tyrosine hydroxylase-immunoreactive fibers in the implanted striata or in amphetamine-induced rotation between killed amnion cell-implanted and saline-injected rats did not reach significance. Implants of live amnion cells into the striatum of a parkinsonian animal model can evoke the de novo appearance of dopaminergic fibers in the denervated striatum and behavioral recovery, most likely through a trophic mechanism.

Long-term evaluation of hemiparkinsonian monkeys after adrenal autografting or cavitation alone.

Autografts of adrenal medulla were implanted into preformed cavities in the caudate nuclei of four rhesus monkeys with hemiparkinsonism induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Five other hemiparkinsonian monkeys underwent caudate cavitation, but received no tissue implant. All of the animals had marked bradykinesia of the affected arm and stable apomorphine-induced turning before cavitation or implantation. Moderate behavioral recovery was seen in all five monkeys with cavitation and two of the three monkey with long-term adrenal autografts (the fourth adrenal recipient was sacrificed 10 days after grafting). The improvement occurred months after the procedure and was not as early or as complete as that seen after fetal dopaminergic grafts. Surviving adrenal tissue was found only in the animal that showed no behavioral recovery. The other two adrenal autograft recipients (with no surviving adrenal medulla) and all of the animals with cavitation had ingrowth of dopaminergic fibers from the area olfactoria and nucleus accumbens into the caudate, oriented toward the cavity. These findings show that the mechanism of improvement after adrenal medullary implants for parkinsonism is not dopamine secretion by chromaffin cells, but may be related to the sprouted host fibers. The results also indicate that the limited recovery after adrenal implants in parkinsonian patients may be a result of the cavitation, and not necessarily the result of tissue implantation.

Evaluation of a rubella hemagglutination inhibition test system.

Two systems for measurement of rubella hemagglutination inhibition antibodies were compared. One had chick erythrocytes as indicator and the other, which is available in kit form ("Rubindex," Ortho-Diagnostics), uses human group O erythrocytes. Correlation to within one dilution of each other was noted in 92% of the tests. The Rubindex system has the advantage of longer shelf life of reagents and also does not require one of the absorption steps necessary for the other method, thus saving technologist's time.