Pannexins (Panxs) are channel-forming proteins that have homology to the invertebrate gap junction proteins, the innexins. These proteins form membrane channels implicated in ATP release. To evaluate the role of Panxs in the male reproductive tract, we investigated the distribution and regulation of Panx1 and 3 in the testis, efferent ducts (ED), and epididymis of adult rats. In the testis, Panx1 localized to the basal compartment of the seminiferous epithelium, while Panx3 was expressed in Leydig cells. In the ED, both Panxs were expressed in the apical region of ciliated cells. In the epididymis, Panx1 was detected at the base of the epithelium, at times encompassing basal cells, while Panx3 was restricted to the apical plasma membrane of principal cells. Panx3 immunoreactions were high throughout the entire epididymis while Panx1 was high in all regions except the initial segment. Multiple transcripts for Panx1 were identified, and sequence analysis indicated that alternative splicing might account for them. Orchidectomy resulted in the expression of multiple immunoreactive Panx1 bands, and these appeared to be androgen-repressed throughout the epididymis. Panx3 levels in all epididymal regions were also androgen-repressed. Deglycosylation experiments indicated that some Panx1 species were due to glycosylation, but this did not account for all Panx1 immunoreactive species. In summary, Panxs expressed in the epididymis and regulated by both alternative splicing events and androgens. These proteins may play a role in ATP secretion into the epididymal lumen and basal extracellular spaces for functions involving sperm transport and maturation.

La distinction entre éthique normative et métaéthique n’implique pas nécessairement une indépendance complète entre ces deux plans théoriques, mais à tout le moins une séparation stricte entre les types de réponses recherchés. Le constructivisme moral semble toutefois échapper à cette règle. S’il s’agit, à première vue, d’une théorie normative, il est également présenté dans la littérature métaéthique comme une troisième voie face à l’alternative réductrice entre un réalisme moral qui doit postuler l’existence de propriétés métaphysiques difficilement conciliables avec le monde naturel et un antiréalisme qui rend bien compte de la force motivationnelle du jugement moral, mais au prix de son objectivité. Il existe toutefois un scepticisme largement partagé – et en partie justifié – quant à cette prétention métaéthique du constructivisme. Il n’est en effet pas toujours très aisé de voir de quelle façon le constructivisme – et quel constructivisme – répond aux questions les plus fondamentales de la métaéthique, qu’il s’agisse de questions d’ordre ontologique, sémantique, épistémologique ou encore psychologique. Ce texte offre quelques pistes afin de voir comment le constructivisme moral peut répondre à ces problèmes de métaéthique, et d’une façon telle qu’elle lui permettrait de se distinguer clairement à la fois du réalisme et de l’expressivisme.

No abstract

One of the main characteristics of today’s democratic societies is their pluralism. As a result, liberal political philosophers often claim that the state should remain neutral with respect to different conceptions of the good. Legal and social policies should be acceptable to everyone regardless of their culture, their religion or their comprehensive moral views. One might think that this commitment to neutrality should be especially pronounced in urban centres, with their culturally diverse populations. However, there are a large number of laws and policies adopted at the municipal level that contradict the liberal principle of neutrality. In this paper, I want to suggest that these perfectionist laws and policies are legitimate at the urban level. Specifically, I will argue that the principle of neutrality applies only indirectly to social institutions within the broader framework of the nation-state. This is clear in the case of voluntary associations, but to a certain extent this rationale applies also to cities. In a liberal regime, private associations are allowed to hold and defend perfectionist views, focused on a particular conception of the good life. One problem is to determine the limits of this perfectionism at the urban level, since cities, unlike private associations, are public institutions. My aim here is therefore to give a liberal justification to a limited form of perfectionism of municipal laws and policies.