Shapiro L S, Roland R M, Li C S, Halpern M
Program in Neural and Behavioral Sciences, Health Science Center at Brooklyn, State University of New York 11203, USA.
Behav Brain Res. 1996 May;77(1-2):101-13. doi: 10.1016/0166-4328(95)00206-5.
The present study was designed to test the hypothesis that preferential nuzzling of unfamiliar conspecific odors by male opossums is vomeronasally mediated. Opossums were presented with vials containing their own odors (Own) and vials with odors from unfamiliar conspecifics (Novel) both before and after (Expt. 1) or only after (Expt. 2) vomeronasal nerve (VNNX) or sham (Sham) surgery. Nuzzling duration was greater for Novel before (Expt. 1) and after (Expts. 1 and 2) surgery both in VNNX and Sham animals, indicating that a functional vomeronasal system is not necessary for the differential nuzzling of novel odors. In contrast, differential scent marking of Novel was lost following VNNX, but not following sham surgery. Since VNNX lesions disrupt differential marking behavior but, not differential nuzzling, it is possible that different components of conspecific odors guide these two chemosensory behaviors and that these components may be detected by different sensory systems. Vomeronasal nerve lesions, confirmed histologically, resulted in the loss of the beta-NADPH-dependent reaction product from the accessory olfactory bulbs (AOB). The pattern of staining with 4 lectins, soybean agglutinin (SBA), Phosphocarpus tetragonolobus (PCT), Vicia villosa agglutinin (VVA), and Griffonia simplicifolia lectin I-isolectin B4 (GS I-B4) remained unchanged in the AOB following vomeronasal nerve lesions, although the size of the AOB appeared to decrease in the VNNX animals.
本研究旨在验证雄性负鼠对陌生同种气味的偏好性轻嗅是由犁鼻器介导的这一假设。在犁鼻神经（VNNX）切断或假手术（Sham）之前和之后（实验1）或仅在之后（实验2），分别给负鼠呈现装有自身气味的小瓶（自身）和装有陌生同种个体气味的小瓶（新奇）。在VNNX组和假手术组动物中，无论是在手术前（实验1）还是手术后（实验1和实验2），负鼠对新奇气味的轻嗅持续时间都更长，这表明功能性犁鼻系统对于区分新奇气味的轻嗅并非必需。相反，VNNX手术后新奇气味的差异性气味标记消失了，但假手术后没有。由于VNNX损伤会破坏差异性标记行为，但不会破坏差异性轻嗅，因此同种气味的不同成分可能引导这两种化学感应行为，并且这些成分可能由不同的感觉系统检测到。经组织学证实，犁鼻神经损伤导致副嗅球（AOB）中β-NADPH依赖性反应产物消失。尽管在VNNX组动物中AOB的大小似乎减小了，但在犁鼻神经损伤后，AOB中大豆凝集素（SBA）、四棱豆凝集素（PCT）、绒毛豌豆凝集素（VVA）和非洲相思子凝集素I-异凝集素B4（GS I-B4）这4种凝集素的染色模式保持不变。
