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In an earlier report from this laboratory, it was demonstrated that the central cholinergic system exerted a modulatory pro-inflammatory effect on carrageenin-induced paw inflammation in rats. In this study, the role of the central muscarinic receptors in cholinergic modulation of peripheral inflammation was investigated by using several M1 and M2 receptor agonists and antagonists. The M1 receptor agonists aceclidine and arecholine and the nonspecific muscarinic receptor agonist oxotremorine augmented carrageenin oedema, an effect attenuated by the M1 receptor antagonist scopolamine. Physostigmine behaved like a M1 receptor agonist at all dose levels. However, the other M2 receptor agonist, carbachol, produced a dose-dependent dual effect, with lower doses attenuating the oedema and higher doses augmenting the inflammation. While the former action appeared to be due to M2 receptor stimulation, because it was blocked by AF-DX 116--a M2 receptor antagonist, the latter action appeared to be induced by M1 receptor stimulation, because it was inhibited by scopolamine. The pro-inflammatory effect of the M2 receptor antagonists AF-DX 116 and gallamine appeared to be induced by enhanced neuronal release of acetylcholine, because the effects were not evident following pretreatment with hemicholinium, which attenuates synthesis of the amine. Muscarinic receptor binding studies with (3H)-QNB indicated that the corpus striatum has substantially higher population of M1 receptors compared with the cerebellum. In the corpus striatum, (3H)-QNB binding indicated initial up-regulation followed by down-regulation of M1 receptors during peak inflammation, which appeared to persist even after a decrease in the inflammation. In contrast, the M1 receptors in the cerebellum appeared to be down-regulated very transiently during the early phase of the inflammation. While these receptor alterations may be due to the inflammation, it is equally possible that they represent changes induced by the stress of pain and inflammation induced by carrageenin.

Results obtained so far on the C3 polymorphism suggest that the system should be a valuable marker in population studies. The instability of the complement component C3 may, however, cause some practical problems in population genetic fieldwork, since a certain fraction of serum samples may be difficult to type with certainity due to storage alterations. Studies of the conversion rate and the concentration of C3 have shown that there is no significant difference between the phenotypes. And furthermore, the fact that there is good agreement with the Hardy-Weinberg distribution indicates that the conversion has had no appreciable selective effect on the phenotype distribution (Brönnestam et al., 1971).

Blood and serum from 17 Macaca mulatta were analysed for haptoglobins, transferrins, 6-phosphogluconate dehydrogenase, adenylate kinase, adenosine deaminase, phosphoglucomutase, acid phosphatase, glucose-6-phosphate dehydrogenase and phosphohexose isomerase. Compared to the human pattern, the AcPh and the ADA components of macaques are fast moving; AK, PGM, 6-PGD and G-6-PG have almost uniform and similar electrophoretic mobilities; and the Hp, Tf and PHI show differential mobilities. All these macaques possess similar karyotypes.

The group-specific component in 17 Macaca mulatta was examined. All the individuals revealed the same Gc 1--1 pattern.