Scholarlink

<p>Hippocampal area CA2 is important for social recognition memory. It has classically been defined as the region between areas CA3 and CA1 where pyramidal cells have larger cell bodies than CA1 neurons, but lack mossy fiber input and thorny excrescences (TEs) typical for CA3 neurons. Based on molecular signatures, the borders of area CA2 have been redefined, with area CA2b now covering parts of former area CA3a. Functional data suggest that CA2b is a mixture of CA3 and CA2 cells, yet information about the spatial distribution of these cells within CA2b remains vague. In the present study, we filled pyramidal cells in dorsal CA3-CA2-CA1, post-hoc identified CA2 cells using Purkinje Cell Protein 4 (PCP4), and analyzed their proximal apical spines using confocal and electron microscopy. We found that dorsal CA2b resembles an intermediate zone between CA3 and CA2a, where CA3 neurons with large TEs are gradually replaced by CA2 neurons. These CA2 neurons are heterogeneous in their scarce display of spines and larger spiny protrusions, rarely also carry TEs, and form synapses with mossy fibers. Thus, morphology needs to be combined with molecular markers to identify CA2 neurons in area CA2b with certainty.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Gradual transition of pyramidal cell types in the dorsal hippocampal area CA2b of the C57BL/6 mouse

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年8月11日

查看全文
  • Meike Fellenz,
  • Rebecca Schneider,
  • Sharif Jabra,
  • Michael Rietsche,
  • Dinko Smilovic,
  • Mario Vuksic,
  • David A. Slattery,
  • Thomas Deller

摘要

Hippocampal area CA2 is important for social recognition memory. It has classically been defined as the region between areas CA3 and CA1 where pyramidal cells have larger cell bodies than CA1 neurons, but lack mossy fiber input and thorny excrescences (TEs) typical for CA3 neurons. Based on molecular signatures, the borders of area CA2 have been redefined, with area CA2b now covering parts of former area CA3a. Functional data suggest that CA2b is a mixture of CA3 and CA2 cells, yet information about the spatial distribution of these cells within CA2b remains vague. In the present study, we filled pyramidal cells in dorsal CA3-CA2-CA1, post-hoc identified CA2 cells using Purkinje Cell Protein 4 (PCP4), and analyzed their proximal apical spines using confocal and electron microscopy. We found that dorsal CA2b resembles an intermediate zone between CA3 and CA2a, where CA3 neurons with large TEs are gradually replaced by CA2 neurons. These CA2 neurons are heterogeneous in their scarce display of spines and larger spiny protrusions, rarely also carry TEs, and form synapses with mossy fibers. Thus, morphology needs to be combined with molecular markers to identify CA2 neurons in area CA2b with certainty.