Mouse opossum

Zonal projections of the inferior olive to the nodulus (lobule X) and the flocculus have been substantiated in different species. Purkinje cells of these lobules are uniformly Zebrin-positive in rat, mouse, opossum, squirrel monkey (see Section 6.1.3.) and rabbit (Jaarsma unpublished observations). A compartmental subdivision of the white matter of the nodulus and the flocculus was demonstrated with AChE-histochemistry in the rabbit and the monkey (Section 6.1.5.) and correlated with the olivocerebellar projection to these lobules (Voogd et al., 1987a,b Tan et al., 1995a,b). 

Boggs, J., 1969, The general and agonistic behavior of the mouse opossum, Marmosa robinsoni, M. S. Thesis, San Diego State Univ., San Diego,... 

Boggs, J. R, 1969, The General Agonistic Behavior of the Mouse Opossum (Marmosa robinsoni), Unpubl. Master s thesisj San Diego State University, San Diego, California. 

Several studies have identified responses that do not involve VN participation, from marsupials to Mouse-lemurs. Where the chosen endpoint is totally unaffected by absence of the organ and in addition is dependent upon MOS activity, then it needs to be classified as VN-independent. Where VN-x results are ambiguous, as already considered for opossums (Monodelphis domestica), further analysis is desirable. For instance, Goats do not use AOS input for mating, only urinalysis, although experiential variables have not been fully explored (Ladewig et al., 1980). Examples of VN independence then exist in both altricial and precocial species. 

Interestingly, Halpern et al. (1995) and Berghard and Buck (1996) identified a G protein subunit, Gao, in the basal part of the vomeronasal epithelium in opossum and mouse, whose distribution was similar to the Fos-like immunoreactivity observed here. Neurons that are extending axons and thus are immature may express Gao, since Gao has been proposed to be important in axonal growth (Berghard and Buck, 1996). Although this localization of Gao is similar to the pattern of our Fos-like immunoreactivity, no functional correlation can be made between the two at this point. 

Extensive studies of the N-terminal sequences of mammalian Vhiu proteins were reported by Capra et al. (132). All H chains that were unblocked at the N-terminus proved to be highly homologous to human Vhiu in sequence. The percentage of unblocked H chains in a normal pool ranged from zero (pig, cow, sheep, goat, mouse, horse, whale) to > 95% (opossum, dog, mink, cat, sea lion, seal). Other species studied have 19-29% unblocked H chains (man, monkey, rat, mouse. 

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