Dataset Information

Morphological differences of the carotid body among C57/BL6 (B6), A/J, and CSS B6A1 mouse strains.

ABSTRACT: The C57/BL6 (B6) mouse strain exhibits post-hypoxic frequency decline and periodic breathing, as well as greater amount of irregular breathing during rest in comparison to the A/J and to the B6a1, a chromosomal substitution strain whereby the A/J chromosome 1 is bred onto the B6 background (Han et al., 2002; Yamauchi et al., 2008a,b). The hypothesis was that morphological differences in the carotid body would associate with such trait variations. After confirming strain differences in post-hypoxic ventilatory behavior, histological examination (n=8 in each group) using hematoxylin and eosin (H&E) staining revealed equivalent, well-defined tissue structure at the bifurcation of the carotid arteries, an active secretory parenchyma (type I cells) from the supportive stromal tissue, and clustering of type I cells in all three strains. Tyrosine hydroxylase (TH) immunohistochemical staining revealed a typical organization of type I cells and neurovascular components into glomeruli in all three strains. Image analysis from 5 ?m sections from each strain generated a series of cytological metrics. The percent carotid body composition of TH+ type I cells in the A/J, B6 and B6a1 was 20±4%, 39±3%, and 44±3%, respectively (p=0.00004). However, cellular organization in terms of density and ultrastructure in the B6a1 is more similar to the B6 than to the A/J. These findings indicate that genetic mechanisms that produce strain differences in ventilatory function do not associate with carotid body structure or tyrosine hydroxylase morphology, and that A/J chromosome 1 does not contribute much to B6 carotid body morphology.

SUBMITTER: Chai S

PROVIDER: S-EPMC4455900 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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Morphological differences of the carotid body among C57/BL6 (B6), A/J, and CSS B6A1 mouse strains.

Chai Sam S Gillombardo Carl B CB Donovan Lucas L Strohl Kingman P KP

Respiratory physiology & neurobiology 20110428 3

The C57/BL6 (B6) mouse strain exhibits post-hypoxic frequency decline and periodic breathing, as well as greater amount of irregular breathing during rest in comparison to the A/J and to the B6a1, a chromosomal substitution strain whereby the A/J chromosome 1 is bred onto the B6 background (Han et al., 2002; Yamauchi et al., 2008a,b). The hypothesis was that morphological differences in the carotid body would associate with such trait variations. After confirming strain differences in post-hypox ...[more]

PMID: 21555000

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Dataset Information

Morphological differences of the carotid body among C57/BL6 (B6), A/J, and CSS B6A1 mouse strains.

Publications

Morphological differences of the carotid body among C57/BL6 (B6), A/J, and CSS B6A1 mouse strains.

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