2 resultados para Rare mammals

em Bucknell University Digital Commons - Pensilvania - USA


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A new genus is proposed for the strikingly patterned African vespertilionid "Glauconycteris" superba Hayman, 1939 on the basis of cranial and external morphological comparisons. A review of the attributes of a newly collected specimen from South Sudan (a new country record) and other museum specimens of "G." superba suggests that "G." superba is markedly distinct ecomorphologically from other species classified in Glauconycteris and is likely the sister taxon to Glauconycteris sensu stricto. The recent capture of this rarely collected but widespread bat highlights the need for continued research in tropical sub-Saharan Africa and in particular, for more work in western South Sudan, which has received very little scientific attention. New country records for G. cf. poensis (South Sudan) and G. curryae (Gabon) are also reported.

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The results of studies using systemic or central applications of cholinergic drugs suggest that acetylcholine makes important contributions to the neurochemical control of male- and female-typical reproductive behaviors. In males, cholinergic control seems largely specific to some elements or aspects of copulatory behavior that can vary significantly across species. Synapses in or near the medial preoptic area represent part of this mechanism, but the entire system appears to extend more widely, perhaps especially to one or more structures flanking some part of the lateral ventricle. In females, the lordosis response that essentially defines sexual receptivity is clearly responsive to cholinergic drugs. The same seems likely to be true of other elements of female sexual behavior, but additional studies will be needed to confirm this. Changes in cholinergic activity may help to mediate estrogenic effects on female sexual behavior. However, estrogen exposure can increase or decrease cholinergic effects, suggesting a relationship that is complex and requires further analysis. Also presently unclear is the localization of the cholinergic effects on female sexual responses. Though periventricular sites again have been implicated, their identity is presently unknown. This review discusses these and other aspects of the central cholinergic systems affecting male and female sexual behaviors. Copyright 2014 Elsevier Inc. All rights reserved.